Integer representation of an angle such that 1024 corresponds to full circle (i.e., 2 * pi). Type used for storing references to cogl objects, the CoglHandle is a fully opaque type without any public data members. When associating private data with a #CoglObject a callback can be given which will be called either if the object is destroyed or if cogl_object_set_user_data() is called with NULL user_data for the same key. Data types for the components of a vertex attribute. Data is the same size of a byte Data is the same size of an unsigned byte Data is the same size of a short integer Data is the same size of an unsigned short integer Data is the same size of a float Creates a bitmap using some existing data. The data is not copied so the application must keep the buffer alive for the lifetime of the #CoglBitmap. This can be used for example with cogl_framebuffer_read_pixels_into_bitmap() to read data directly into an application buffer with the specified rowstride. A new #CoglBitmap. A #CoglContext The width of the bitmap. The height of the bitmap. The format of the pixel data. The rowstride of the bitmap (the number of bytes from the start of one row of the bitmap to the next). A pointer to the data. The bitmap will take ownership of this data. Wraps some image data that has been uploaded into a #CoglBuffer as a #CoglBitmap. The data is not copied in this process. a #CoglBitmap encapsulating the given @buffer. A #CoglBuffer containing image data The #CoglPixelFormat defining the format of the image data in the given @buffer. The width of the image data in the given @buffer. The height of the image data in the given @buffer. The rowstride in bytes of the image data in the given @buffer. The offset into the given @buffer to the first pixel that should be considered part of the #CoglBitmap. Loads an image file from disk. This function can be safely called from within a thread. a #CoglBitmap to the new loaded image data, or %NULL if loading the image failed. the file to load. Creates a new #CoglBitmap with the given width, height and format. The initial contents of the bitmap are undefined. The data for the bitmap will be stored in a newly created #CoglPixelBuffer. You can get a pointer to the pixel buffer using cogl_bitmap_get_buffer(). The #CoglBuffer API can then be used to fill the bitmap with data. <note>Cogl will try its best to provide a hardware array you can map, write into and effectively do a zero copy upload when creating a texture from it with cogl_texture_new_from_bitmap(). For various reasons, such arrays are likely to have a stride larger than width * bytes_per_pixel. The user must take the stride into account when writing into it. The stride can be retrieved with cogl_bitmap_get_rowstride().</note> a #CoglPixelBuffer representing the newly created array or %NULL on failure A #CoglContext width of the bitmap in pixels height of the bitmap in pixels the format of the pixels the array will store Parses an image file enough to extract the width and height of the bitmap. %TRUE if the image was successfully parsed the file to check return location for the bitmap width, or %NULL return location for the bitmap height, or %NULL the #CoglPixelBuffer that this buffer uses for storage. Note that if the bitmap was created with cogl_bitmap_new_from_file() then it will not actually be using a pixel buffer and this function will return %NULL. A #CoglBitmap the #CoglPixelFormat that the data for the bitmap is in. A #CoglBitmap the height of the bitmap A #CoglBitmap the rowstride of the bitmap. This is the number of bytes between the address of start of one row to the address of the next row in the image. A #CoglBitmap the width of the bitmap A #CoglBitmap Error codes that can be thrown when performing bitmap operations. Note that gdk_pixbuf_new_from_file() can also throw errors directly from the underlying image loading library. For example, if GdkPixbuf is used then errors #GdkPixbufError<!-- -->s will be used directly. Generic failure code, something went wrong. Unknown image type. An image file was broken somehow. Error enumeration for the blend strings parser Generic parse error Argument parse error Internal parser error Blend string not supported by the GPU Types of auxiliary buffers Selects the primary color buffer Selects the depth buffer Selects the stencil buffer Target flags for FBOs. FIXME FIXME A structure for holding a color definition. The contents of the CoglColor structure are private and should never by accessed directly. Creates a new (empty) color a newly-allocated #CoglColor. Use cogl_color_free() to free the allocated resources Creates a copy of @color a newly-allocated #CoglColor. Use cogl_color_free() to free the allocate resources the color to copy Frees the resources allocated by cogl_color_new() and cogl_color_copy() the color to free Retrieves the alpha channel of @color as a fixed point value between 0 and 1.0. the alpha channel of the passed color a #CoglColor Retrieves the alpha channel of @color as a byte value between 0 and 255 the alpha channel of the passed color a #CoglColor Retrieves the alpha channel of @color as a floating point value between 0.0 and 1.0 the alpha channel of the passed color a #CoglColor Retrieves the blue channel of @color as a fixed point value between 0 and 1.0. the blue channel of the passed color a #CoglColor Retrieves the blue channel of @color as a byte value between 0 and 255 the blue channel of the passed color a #CoglColor Retrieves the blue channel of @color as a floating point value between 0.0 and 1.0 the blue channel of the passed color a #CoglColor Retrieves the green channel of @color as a fixed point value between 0 and 1.0. the green channel of the passed color a #CoglColor Retrieves the green channel of @color as a byte value between 0 and 255 the green channel of the passed color a #CoglColor Retrieves the green channel of @color as a floating point value between 0.0 and 1.0 the green channel of the passed color a #CoglColor Retrieves the red channel of @color as a fixed point value between 0 and 1.0. the red channel of the passed color a #CoglColor Retrieves the red channel of @color as a byte value between 0 and 255 the red channel of the passed color a #CoglColor Retrieves the red channel of @color as a floating point value between 0.0 and 1.0 the red channel of the passed color a #CoglColor Sets the values of the passed channels into a #CoglColor A pointer to a #CoglColor to initialize value of the red channel, between 0 and 1.0 value of the green channel, between 0 and 1.0 value of the blue channel, between 0 and 1.0 value of the alpha channel, between 0 and 1.0 Sets the values of the passed channels into a #CoglColor A pointer to a #CoglColor to initialize a pointer to an array of 4 float color components Sets the values of the passed channels into a #CoglColor. A pointer to a #CoglColor to initialize value of the red channel, between 0 and 255 value of the green channel, between 0 and 255 value of the blue channel, between 0 and 255 value of the alpha channel, between 0 and 255 Converts a non-premultiplied color to a pre-multiplied color. For example, semi-transparent red is (1.0, 0, 0, 0.5) when non-premultiplied and (0.5, 0, 0, 0.5) when premultiplied. the color to premultiply Sets the alpha channel of @color to @alpha. a #CoglColor a float value between 0.0f and 1.0f Sets the alpha channel of @color to @alpha. a #CoglColor a byte value between 0 and 255 Sets the alpha channel of @color to @alpha. a #CoglColor a float value between 0.0f and 1.0f Sets the blue channel of @color to @blue. a #CoglColor a float value between 0.0f and 1.0f Sets the blue channel of @color to @blue. a #CoglColor a byte value between 0 and 255 Sets the blue channel of @color to @blue. a #CoglColor a float value between 0.0f and 1.0f Sets the green channel of @color to @green. a #CoglColor a float value between 0.0f and 1.0f Sets the green channel of @color to @green. a #CoglColor a byte value between 0 and 255 Sets the green channel of @color to @green. a #CoglColor a float value between 0.0f and 1.0f Sets the red channel of @color to @red. a #CoglColor a float value between 0.0f and 1.0f Sets the red channel of @color to @red. a #CoglColor a byte value between 0 and 255 Sets the red channel of @color to @red. a #CoglColor a float value between 0.0f and 1.0f Converts @color to the HLS format. The @hue value is in the 0 .. 360 range. The @luminance and @saturation values are in the 0 .. 1 range. a #CoglColor return location for the hue value or %NULL return location for the saturation value or %NULL return location for the luminance value or %NULL Converts a pre-multiplied color to a non-premultiplied color. For example, semi-transparent red is (0.5, 0, 0, 0.5) when premultiplied and (1.0, 0, 0, 0.5) when non-premultiplied. the color to unpremultiply Compares two #CoglColor<!-- -->s and checks if they are the same. This function can be passed to g_hash_table_new() as the @key_equal_func parameter, when using #CoglColor<!-- -->s as keys in a #GHashTable. %TRUE if the two colors are the same. a #CoglColor a #CoglColor Converts a color expressed in HLS (hue, luminance and saturation) values into a #CoglColor. return location for a #CoglColor hue value, in the 0 .. 360 range saturation value, in the 0 .. 1 range luminance value, in the 0 .. 1 range Creates a new #CoglContext which acts as an application sandbox for any state objects that are allocated. A newly allocated #CoglContext A #CoglDisplay pointer Retrieves the #CoglDisplay that is internally associated with the given @context. This will return the same #CoglDisplay that was passed to cogl_context_new() or if %NULL was passed to cogl_context_new() then this function returns a pointer to the display that was automatically setup internally. The #CoglDisplay associated with the given @context. A #CoglContext pointer This function should only be called if the COGL_FEATURE_ID_TIMESTAMP_QUERY feature is advertised. Current GPU time in nanoseconds a #CoglContext pointer The #CoglPipeline associated with the given @context and @key, or %NULL if no such #CoglPipeline was found. a #CoglContext pointer a #CoglPipelineKey pointer Retrieves the #CoglRenderer that is internally associated with the given @context. This will return the same #CoglRenderer that was passed to cogl_display_new() or if %NULL was passed to cogl_display_new() or cogl_context_new() then this function returns a pointer to the renderer that was automatically connected internally. The #CoglRenderer associated with the given @context. A #CoglContext pointer %TRUE if the @context is hardware accelerated, or %FALSE if not. a #CoglContext pointer Associate a #CoglPipeline with a @context and @key. This will not take a new reference to the @pipeline, but will unref all associated pipelines when the @context gets destroyed. Similarly, if a pipeline gets overwritten, it will get unreffed as well. a #CoglContext pointer a #CoglPipelineKey pointer a #CoglPipeline to associate with the @context and @key A callback function to use for cogl_debug_object_foreach_type(). A pointer to a struct containing information about the type. This struct is used to pass information to the callback when cogl_debug_object_foreach_type() is called. A human readable name for the type. The number of objects of this type that are currently in use When using depth testing one of these functions is used to compare the depth of an incoming fragment against the depth value currently stored in the depth buffer. The function is changed using cogl_depth_state_set_test_function(). The test is only done when depth testing is explicitly enabled. (See cogl_depth_state_set_test_enabled()) Never passes. Passes if the fragment's depth value is less than the value currently in the depth buffer. Passes if the fragment's depth value is equal to the value currently in the depth buffer. Passes if the fragment's depth value is less or equal to the value currently in the depth buffer. Passes if the fragment's depth value is greater than the value currently in the depth buffer. Passes if the fragment's depth value is not equal to the value currently in the depth buffer. Passes if the fragment's depth value greater than or equal to the value currently in the depth buffer. Always passes. An opaque type that tracks the lifetime of a DMA buffer fd. Release with cogl_dma_buf_handle_free(). A callback used with cogl_foreach_feature() for enumerating all context level features supported by Cogl. A single feature currently supported by Cogl A private pointer passed to cogl_foreach_feature(). All the capabilities that can vary between different GPUs supported by Cogl. Applications that depend on any of these features should explicitly check for them using cogl_has_feature() or cogl_has_features(). Set if %COGL_INDICES_TYPE_UNSIGNED_INT is supported in cogl_indices_new(). Whether cogl_buffer_map() is supported with CoglBufferAccess including read support. Whether cogl_buffer_map() is supported with CoglBufferAccess including write support. Support for %COGL_TEXTURE_COMPONENTS_RG as the internal components of a texture. Available if the age of #CoglOnscreen back buffers are tracked and so cogl_onscreen_get_buffer_age() can be expected to return age values other than 0. Whether blitting using cogl_blit_framebuffer() is supported. Return values for the #CoglXlibFilterFunc and #CoglWin32FilterFunc functions. The event was not handled, continues the processing Remove the event, stops the processing Is a callback that can be registered via cogl_onscreen_add_frame_callback() to be called when a frame progresses in some notable way. Please see the documentation for #CoglFrameEvent and cogl_onscreen_add_frame_callback() for more details about what events can be notified. The onscreen that the frame is associated with A #CoglFrameEvent notifying how the frame has progressed The meta information, such as timing information, about the frame that has progressed. The user pointer passed to cogl_onscreen_add_frame_callback() An opaque type that tracks a #CoglFrameCallback and associated user data. A #CoglFrameClosure pointer will be returned from cogl_onscreen_add_frame_callback() and it allows you to remove a callback later using cogl_onscreen_remove_frame_callback(). Identifiers that are passed to #CoglFrameCallback functions (registered using cogl_onscreen_add_frame_callback()) that mark the progression of a frame in some way which usually means that new information will have been accumulated in the frame's corresponding #CoglFrameInfo object. The last event that will be sent for a frame will be a @COGL_FRAME_EVENT_COMPLETE event and so these are a good opportunity to collect statistics about a frame since the #CoglFrameInfo should hold the most data at this point. <note>A frame may not be completed before the next frame can start so applications should avoid needing to collect all statistics for a particular frame before they can start a new frame.</note> Notifies that the system compositor has acknowledged a frame and is ready for a new frame to be created. Notifies that a frame has ended. This is a good time for applications to collect statistics about the frame since the #CoglFrameInfo should hold the most data at this point. No other events should be expected after a @COGL_FRAME_EVENT_COMPLETE event. Frame information. Gets the frame counter for the #CoglOnscreen that corresponds to this frame. The frame counter value a #CoglFrameInfo object Gets the presentation time for the frame. This is the time at which the frame became visible to the user. The presentation time measured in microseconds, is based on CLOCK_MONOTONIC. <note>Some buggy Mesa drivers up to 9.0.1 may incorrectly report non-monotonic timestamps.</note> the presentation time for the frame a #CoglFrameInfo object Gets the refresh rate in Hertz for the output that the frame was on at the time the frame was presented. <note>Some platforms can't associate a #CoglOutput with a #CoglFrameInfo object but are able to report a refresh rate via this api. Therefore if you need this information then this api is more reliable than using cogl_frame_info_get_output() followed by cogl_output_get_refresh_rate().</note> the refresh rate in Hertz a #CoglFrameInfo object Explicitly allocates a configured #CoglFramebuffer allowing developers to check and handle any errors that might arise from an unsupported configuration so that fallback configurations may be tried. <note>Many applications don't support any fallback options at least when they are initially developed and in that case the don't need to use this API since Cogl will automatically allocate a framebuffer when it first gets used. The disadvantage of relying on automatic allocation is that the program will abort with an error message if there is an error during automatic allocation.</note> %TRUE if there were no error allocating the framebuffer, else %FALSE. A #CoglFramebuffer Explicitly allocates a configured #CoglFramebuffer allowing developers to check and handle any errors that might arise from an unsupported configuration so that fallback configurations may be tried. <note>Many applications don't support any fallback options at least when they are initially developed and in that case the don't need to use this API since Cogl will automatically allocate a framebuffer when it first gets used. The disadvantage of relying on automatic allocation is that the program will abort with an error message if there is an error during automatic allocation.</note> %TRUE if there were no error allocating the framebuffer, else %FALSE. A #CoglFramebuffer Clears all the auxiliary buffers identified in the @buffers mask, and if that includes the color buffer then the specified @color is used. A #CoglFramebuffer A mask of #CoglBufferBit<!-- -->'s identifying which auxiliary buffers to clear The color to clear the color buffer too if specified in @buffers. Clears all the auxiliary buffers identified in the @buffers mask, and if that includes the color buffer then the specified @color is used. A #CoglFramebuffer A mask of #CoglBufferBit<!-- -->'s identifying which auxiliary buffers to clear The red component of color to clear the color buffer too if specified in @buffers. The green component of color to clear the color buffer too if specified in @buffers. The blue component of color to clear the color buffer too if specified in @buffers. The alpha component of color to clear the color buffer too if specified in @buffers. Creates a query for the GPU timestamp that will complete upon completion of all previously submitted GL commands related to this framebuffer. E.g. when the rendering is finished on this framebuffer. This function should only be called if the COGL_FEATURE_ID_TIMESTAMP_QUERY feature is advertised. Declares that the specified @buffers no longer need to be referenced by any further rendering commands. This can be an important optimization to avoid subsequent frames of rendering depending on the results of a previous frame. For example; some tile-based rendering GPUs are able to avoid allocating and accessing system memory for the depth and stencil buffer so long as these buffers are not required as input for subsequent frames and that can save a significant amount of memory bandwidth used to save and restore their contents to system memory between frames. It is currently considered an error to try and explicitly discard the color buffer by passing %COGL_BUFFER_BIT_COLOR. This is because the color buffer is already implicitly discard when you finish rendering to a #CoglOnscreen framebuffer, and it's not meaningful to try and discard the color buffer of a #CoglOffscreen framebuffer since they are single-buffered. A #CoglFramebuffer A #CoglBufferBit mask of which ancillary buffers you want to discard. Draws a textured rectangle to @framebuffer with the given @pipeline state with the top left corner positioned at (@x_1, @y_1) and the bottom right corner positioned at (@x_2, @y_2). As a pipeline may contain multiple texture layers this interface lets you supply texture coordinates for each layer of the pipeline. <note>The position is the position before the rectangle has been transformed by the model-view matrix and the projection matrix.</note> This is a high level drawing api that can handle any kind of #CoglMetaTexture texture for the first layer such as #CoglTexture2DSliced textures which may internally be comprised of multiple low-level textures. This is unlike low-level drawing apis such as cogl_primitive_draw() which only support low level texture types that are directly supported by GPUs such as #CoglTexture2D. <note>This api can not currently handle multiple high-level meta texture layers. The first layer may be a high level meta texture such as #CoglTexture2DSliced but all other layers much be low level textures such as #CoglTexture2D. The top left texture coordinate for layer 0 of any pipeline will be (tex_coords[0], tex_coords[1]) and the bottom right coordinate will be (tex_coords[2], tex_coords[3]). The coordinates for layer 1 would be (tex_coords[4], tex_coords[5]) (tex_coords[6], tex_coords[7]) and so on... The given texture coordinates should always be normalized such that (0, 0) corresponds to the top left and (1, 1) corresponds to the bottom right. To map an entire texture across the rectangle pass in tex_coords[0]=0, tex_coords[1]=0, tex_coords[2]=1, tex_coords[3]=1. The first pair of coordinates are for the first layer (with the smallest layer index) and if you supply less texture coordinates than there are layers in the current source material then default texture coordinates (0.0, 0.0, 1.0, 1.0) are generated. A destination #CoglFramebuffer A #CoglPipeline state object x coordinate upper left on screen. y coordinate upper left on screen. x coordinate lower right on screen. y coordinate lower right on screen. An array containing groups of 4 float values: [s_1, t_1, s_2, t_2] that are interpreted as two texture coordinates; one for the top left texel, and one for the bottom right texel. Each value should be between 0.0 and 1.0, where the coordinate (0.0, 0.0) represents the top left of the texture, and (1.0, 1.0) the bottom right. The length of the @tex_coords array. (For one layer and one group of texture coordinates, this would be 4) Draws a rectangle to @framebuffer with the given @pipeline state and with the top left corner positioned at (@x_1, @y_1) and the bottom right corner positioned at (@x_2, @y_2). <note>The position is the position before the rectangle has been transformed by the model-view matrix and the projection matrix.</note> <note>If you want to describe a rectangle with a texture mapped on it then you can use cogl_framebuffer_draw_textured_rectangle().</note> A destination #CoglFramebuffer A #CoglPipeline state object X coordinate of the top-left corner Y coordinate of the top-left corner X coordinate of the bottom-right corner Y coordinate of the bottom-right corner Draws a series of rectangles to @framebuffer with the given @pipeline state in the same way that cogl_framebuffer_draw_rectangle() does. The top left corner of the first rectangle is positioned at (coordinates[0], coordinates[1]) and the bottom right corner is positioned at (coordinates[2], coordinates[3]). The positions for the second rectangle are (coordinates[4], coordinates[5]) and (coordinates[6], coordinates[7]) and so on... <note>The position is the position before the rectangle has been transformed by the model-view matrix and the projection matrix.</note> As a general rule for better performance its recommended to use this this API instead of calling cogl_framebuffer_draw_textured_rectangle() separately for multiple rectangles if all of the rectangles will be drawn together with the same @pipeline state. A destination #CoglFramebuffer A #CoglPipeline state object an array of coordinates containing groups of 4 float values: [x_1, y_1, x_2, y_2] that are interpreted as two position coordinates; one for the top left of the rectangle (x1, y1), and one for the bottom right of the rectangle (x2, y2). number of rectangles defined in @coordinates. Draws a textured rectangle to @framebuffer using the given @pipeline state with the top left corner positioned at (@x_1, @y_1) and the bottom right corner positioned at (@x_2, @y_2). The top left corner will have texture coordinates of (@s_1, @t_1) and the bottom right corner will have texture coordinates of (@s_2, @t_2). <note>The position is the position before the rectangle has been transformed by the model-view matrix and the projection matrix.</note> This is a high level drawing api that can handle any kind of #CoglMetaTexture texture such as #CoglTexture2DSliced textures which may internally be comprised of multiple low-level textures. This is unlike low-level drawing apis such as cogl_primitive_draw() which only support low level texture types that are directly supported by GPUs such as #CoglTexture2D. <note>The given texture coordinates will only be used for the first texture layer of the pipeline and if your pipeline has more than one layer then all other layers will have default texture coordinates of @s_1=0.0 @t_1=0.0 @s_2=1.0 @t_2=1.0 </note> The given texture coordinates should always be normalized such that (0, 0) corresponds to the top left and (1, 1) corresponds to the bottom right. To map an entire texture across the rectangle pass in @s_1=0, @t_1=0, @s_2=1, @t_2=1. A destination #CoglFramebuffer A #CoglPipeline state object x coordinate upper left on screen. y coordinate upper left on screen. x coordinate lower right on screen. y coordinate lower right on screen. S texture coordinate of the top-left coorner T texture coordinate of the top-left coorner S texture coordinate of the bottom-right coorner T texture coordinate of the bottom-right coorner Draws a series of rectangles to @framebuffer with the given @pipeline state in the same way that cogl_framebuffer_draw_textured_rectangle() does. <note>The position is the position before the rectangle has been transformed by the model-view matrix and the projection matrix.</note> This is a high level drawing api that can handle any kind of #CoglMetaTexture texture such as #CoglTexture2DSliced textures which may internally be comprised of multiple low-level textures. This is unlike low-level drawing apis such as cogl_primitive_draw() which only support low level texture types that are directly supported by GPUs such as #CoglTexture2D. The top left corner of the first rectangle is positioned at (coordinates[0], coordinates[1]) and the bottom right corner is positioned at (coordinates[2], coordinates[3]). The top left texture coordinate is (coordinates[4], coordinates[5]) and the bottom right texture coordinate is (coordinates[6], coordinates[7]). The coordinates for subsequent rectangles are defined similarly by the subsequent coordinates. As a general rule for better performance its recommended to use this this API instead of calling cogl_framebuffer_draw_textured_rectangle() separately for multiple rectangles if all of the rectangles will be drawn together with the same @pipeline state. The given texture coordinates should always be normalized such that (0, 0) corresponds to the top left and (1, 1) corresponds to the bottom right. To map an entire texture across the rectangle pass in tex_coords[0]=0, tex_coords[1]=0, tex_coords[2]=1, tex_coords[3]=1. A destination #CoglFramebuffer A #CoglPipeline state object an array containing groups of 8 float values: [x_1, y_1, x_2, y_2, s_1, t_1, s_2, t_2] that have the same meaning as the arguments for cogl_framebuffer_draw_textured_rectangle(). number of rectangles to @coordinates to draw This blocks the CPU until all pending rendering associated with the specified framebuffer has completed. It's very rare that developers should ever need this level of synchronization with the GPU and should never be used unless you clearly understand why you need to explicitly force synchronization. One example might be for benchmarking purposes to be sure timing measurements reflect the time that the GPU is busy for not just the time it takes to queue rendering commands. A #CoglFramebuffer pointer Flushes @framebuffer to ensure the current batch of commands is submitted to the GPU. Unlike cogl_framebuffer_finish(), this does not block the CPU. A #CoglFramebuffer pointer Replaces the current projection matrix with a perspective matrix for a given viewing frustum defined by 4 side clip planes that all cross through the origin and 2 near and far clip planes. A #CoglFramebuffer pointer X position of the left clipping plane where it intersects the near clipping plane X position of the right clipping plane where it intersects the near clipping plane Y position of the bottom clipping plane where it intersects the near clipping plane Y position of the top clipping plane where it intersects the near clipping plane The distance to the near clipping plane (Must be positive) The distance to the far clipping plane (Must be positive) Retrieves the number of alpha bits of @framebuffer the number of bits a pointer to a #CoglFramebuffer Retrieves the number of blue bits of @framebuffer the number of bits a pointer to a #CoglFramebuffer Can be used to query the #CoglContext a given @framebuffer was instantiated within. This is the #CoglContext that was passed to cogl_onscreen_new() for example. The #CoglContext that the given @framebuffer was instantiated within. A #CoglFramebuffer Retrieves the number of depth bits of @framebuffer the number of bits a pointer to a #CoglFramebuffer Queries whether depth buffer writing is enabled for @framebuffer. This can be controlled via cogl_framebuffer_set_depth_write_enabled(). %TRUE if depth writing is enabled or %FALSE if not. a pointer to a #CoglFramebuffer Returns whether dithering has been requested for the given @framebuffer. See cogl_framebuffer_set_dither_enabled() for more details about dithering. <note>This may return %TRUE even when the underlying @framebuffer display pipeline does not support dithering. This value only represents the user's request for dithering.</note> %TRUE if dithering has been requested or %FALSE if not. a pointer to a #CoglFramebuffer Retrieves the number of green bits of @framebuffer the number of bits a pointer to a #CoglFramebuffer Queries the current height of the given @framebuffer. The height of @framebuffer. A #CoglFramebuffer Stores the current model-view matrix in @matrix. A #CoglFramebuffer pointer return location for the model-view matrix Stores the current projection matrix in @matrix. A #CoglFramebuffer pointer return location for the projection matrix Retrieves the number of red bits of @framebuffer the number of bits a pointer to a #CoglFramebuffer Gets the number of points that are sampled per-pixel when rasterizing geometry. Usually by default this will return 0 which means that single-sample not multisample rendering has been chosen. When using a GPU supporting multisample rendering it's possible to increase the number of samples per pixel using cogl_framebuffer_set_samples_per_pixel(). Calling cogl_framebuffer_get_samples_per_pixel() before the framebuffer has been allocated will simply return the value set using cogl_framebuffer_set_samples_per_pixel(). After the framebuffer has been allocated the value will reflect the actual number of samples that will be made by the GPU. The number of point samples made per pixel when rasterizing geometry or 0 if single-sample rendering has been chosen. A #CoglFramebuffer framebuffer Gets the current #CoglStereoMode, which defines which stereo buffers should be drawn to. See cogl_framebuffer_set_stereo_mode(). A #CoglStereoMode a pointer to a #CoglFramebuffer Queries the x, y, width and height components of the current viewport as set using cogl_framebuffer_set_viewport() or the default values which are 0, 0, framebuffer_width and framebuffer_height. The values are written into the given @viewport array. A #CoglFramebuffer A pointer to an array of 4 floats to receive the (x, y, width, height) components of the current viewport. Queries the height of the viewport as set using cogl_framebuffer_set_viewport() or the default value which is the height of the framebuffer. The height of the viewport. A #CoglFramebuffer Queries the width of the viewport as set using cogl_framebuffer_set_viewport() or the default value which is the width of the framebuffer. The width of the viewport. A #CoglFramebuffer Queries the x coordinate of the viewport origin as set using cogl_framebuffer_set_viewport() or the default value which is 0. The x coordinate of the viewport origin. A #CoglFramebuffer Queries the y coordinate of the viewport origin as set using cogl_framebuffer_set_viewport() or the default value which is 0. The y coordinate of the viewport origin. A #CoglFramebuffer Queries the current width of the given @framebuffer. The width of @framebuffer. A #CoglFramebuffer Resets the current model-view matrix to the identity matrix. A #CoglFramebuffer pointer Replaces the current projection matrix with an orthographic projection matrix. A #CoglFramebuffer pointer The x coordinate for the first vertical clipping plane The y coordinate for the first horizontal clipping plane The x coordinate for the second vertical clipping plane The y coordinate for the second horizontal clipping plane The <emphasis>distance</emphasis> to the near clipping plane (will be <emphasis>negative</emphasis> if the plane is behind the viewer) The <emphasis>distance</emphasis> to the far clipping plane (will be <emphasis>negative</emphasis> if the plane is behind the viewer) Replaces the current projection matrix with a perspective matrix based on the provided values. <note>You should be careful not to have to great a @z_far / @z_near ratio since that will reduce the effectiveness of depth testing since there won't be enough precision to identify the depth of objects near to each other.</note> A #CoglFramebuffer pointer Vertical field of view angle in degrees. The (width over height) aspect ratio for display The distance to the near clipping plane (Must be positive, and must not be 0) The distance to the far clipping plane (Must be positive) Reverts the clipping region to the state before the last call to cogl_framebuffer_push_scissor_clip(), cogl_framebuffer_push_rectangle_clip() cogl_framebuffer_push_path_clip(), or cogl_framebuffer_push_primitive_clip(). A #CoglFramebuffer pointer Restores the model-view matrix on the top of the matrix stack. A #CoglFramebuffer pointer Copies the current model-view matrix onto the matrix stack. The matrix can later be restored with cogl_framebuffer_pop_matrix(). A #CoglFramebuffer pointer Sets a new clipping area using a 2D shaped described with a #CoglPrimitive. The shape must not contain self overlapping geometry and must lie on a single 2D plane. A bounding box of the 2D shape in local coordinates (the same coordinates used to describe the shape) must be given. It is acceptable for the bounds to be larger than the true bounds but behaviour is undefined if the bounds are smaller than the true bounds. The primitive is transformed by the current model-view matrix and the silhouette is intersected with the previous clipping area. To restore the previous clipping area, call cogl_framebuffer_pop_clip(). A #CoglFramebuffer pointer A #CoglPrimitive describing a flat 2D shape x coordinate for the top-left corner of the primitives bounds y coordinate for the top-left corner of the primitives bounds x coordinate for the bottom-right corner of the primitives bounds. y coordinate for the bottom-right corner of the primitives bounds. Specifies a modelview transformed rectangular clipping area for all subsequent drawing operations. Any drawing commands that extend outside the rectangle will be clipped so that only the portion inside the rectangle will be displayed. The rectangle dimensions are transformed by the current model-view matrix. The rectangle is intersected with the current clip region. To undo the effect of this function, call cogl_framebuffer_pop_clip(). A #CoglFramebuffer pointer x coordinate for top left corner of the clip rectangle y coordinate for top left corner of the clip rectangle x coordinate for bottom right corner of the clip rectangle y coordinate for bottom right corner of the clip rectangle Specifies a rectangular clipping area for all subsequent drawing operations. Any drawing commands that extend outside the rectangle will be clipped so that only the portion inside the rectangle will be displayed. The rectangle dimensions are not transformed by the current model-view matrix. The rectangle is intersected with the current clip region. To undo the effect of this function, call cogl_framebuffer_pop_clip(). A #CoglFramebuffer pointer left edge of the clip rectangle in window coordinates top edge of the clip rectangle in window coordinates width of the clip rectangle height of the clip rectangle This is a convenience wrapper around cogl_framebuffer_read_pixels_into_bitmap() which allocates a temporary #CoglBitmap to read pixel data directly into the given buffer. The rowstride of the buffer is assumed to be the width of the region times the bytes per pixel of the format. The source for the data is always taken from the color buffer. If you want to use any other rowstride or source, please use the cogl_framebuffer_read_pixels_into_bitmap() function directly. The implementation of the function looks like this: |[ bitmap = cogl_bitmap_new_for_data (context, width, height, format, /<!-- -->* rowstride *<!-- -->/ bpp * width, pixels); cogl_framebuffer_read_pixels_into_bitmap (framebuffer, x, y, COGL_READ_PIXELS_COLOR_BUFFER, bitmap); cogl_object_unref (bitmap); ]| %TRUE if the read succeeded or %FALSE otherwise. A #CoglFramebuffer The x position to read from The y position to read from The width of the region of rectangles to read The height of the region of rectangles to read The pixel format to store the data in The address of the buffer to store the data in This reads a rectangle of pixels from the given framebuffer where position (0, 0) is the top left. The pixel at (x, y) is the first read, and a rectangle of pixels with the same size as the bitmap is read right and downwards from that point. Currently Cogl assumes that the framebuffer is in a premultiplied format so if the format of @bitmap is non-premultiplied it will convert it. To read the pixel values without any conversion you should either specify a format that doesn't use an alpha channel or use one of the formats ending in PRE. %TRUE if the read succeeded or %FALSE otherwise. The function is only likely to fail if the bitmap points to a pixel buffer and it could not be mapped. A #CoglFramebuffer The x position to read from The y position to read from Identifies which auxiliary buffer you want to read (only COGL_READ_PIXELS_COLOR_BUFFER supported currently) The bitmap to store the results in. When point sample rendering (also known as multisample rendering) has been enabled via cogl_framebuffer_set_samples_per_pixel() then you can optionally call this function (or cogl_framebuffer_resolve_samples_region()) to explicitly resolve the point samples into values for the final color buffer. Some GPUs will implicitly resolve the point samples during rendering and so this function is effectively a nop, but with other architectures it is desirable to defer the resolve step until the end of the frame. Since Cogl will automatically ensure samples are resolved if the target color buffer is used as a source this API only needs to be used if explicit control is desired - perhaps because you want to ensure that the resolve is completed in advance to avoid later having to wait for the resolve to complete. If you are performing incremental updates to a framebuffer you should consider using cogl_framebuffer_resolve_samples_region() instead to avoid resolving redundant pixels. A #CoglFramebuffer framebuffer When point sample rendering (also known as multisample rendering) has been enabled via cogl_framebuffer_set_samples_per_pixel() then you can optionally call this function (or cogl_framebuffer_resolve_samples()) to explicitly resolve the point samples into values for the final color buffer. Some GPUs will implicitly resolve the point samples during rendering and so this function is effectively a nop, but with other architectures it is desirable to defer the resolve step until the end of the frame. Use of this API is recommended if incremental, small updates to a framebuffer are being made because by default Cogl will implicitly resolve all the point samples of the framebuffer which can result in redundant work if only a small number of samples have changed. Because some GPUs implicitly resolve point samples this function only guarantees that at-least the region specified will be resolved and if you have rendered to a larger region then it's possible that other samples may be implicitly resolved. A #CoglFramebuffer framebuffer top-left x coordinate of region to resolve top-left y coordinate of region to resolve width of region to resolve height of region to resolve Multiplies the current model-view matrix by one that rotates the model around the axis-vector specified by @x, @y and @z. The rotation follows the right-hand thumb rule so for example rotating by 10 degrees about the axis-vector (0, 0, 1) causes a small counter-clockwise rotation. A #CoglFramebuffer pointer Angle in degrees to rotate. X-component of vertex to rotate around. Y-component of vertex to rotate around. Z-component of vertex to rotate around. Multiplies the current model-view matrix by one that rotates according to the rotation described by @euler. A #CoglFramebuffer pointer A #graphene_euler_t Multiplies the current model-view matrix by one that scales the x, y and z axes by the given values. A #CoglFramebuffer pointer Amount to scale along the x-axis Amount to scale along the y-axis Amount to scale along the z-axis Enables or disables depth buffer writing when rendering to @framebuffer. If depth writing is enabled for both the framebuffer and the rendering pipeline, and the framebuffer has an associated depth buffer, depth information will be written to this buffer during rendering. Depth buffer writing is enabled by default. a pointer to a #CoglFramebuffer %TRUE to enable depth writing or %FALSE to disable Enables or disabled dithering if supported by the hardware. Dithering is a hardware dependent technique to increase the visible color resolution beyond what the underlying hardware supports by playing tricks with the colors placed into the framebuffer to give the illusion of other colors. (For example this can be compared to half-toning used by some news papers to show varying levels of grey even though their may only be black and white are available). If the current display pipeline for @framebuffer does not support dithering then this has no affect. Dithering is enabled by default. a pointer to a #CoglFramebuffer %TRUE to enable dithering or %FALSE to disable Sets @matrix as the new model-view matrix. A #CoglFramebuffer pointer the new model-view matrix Sets @matrix as the new projection matrix. A #CoglFramebuffer pointer the new projection matrix Requires that when rendering to @framebuffer then @n point samples should be made per pixel which will all contribute to the final resolved color for that pixel. The idea is that the hardware aims to get quality similar to what you would get if you rendered everything twice as big (for 4 samples per pixel) and then scaled that image back down with filtering. It can effectively remove the jagged edges of polygons and should be more efficient than if you were to manually render at a higher resolution and downscale because the hardware is often able to take some shortcuts. For example the GPU may only calculate a single texture sample for all points of a single pixel, and for tile based architectures all the extra sample data (such as depth and stencil samples) may be handled on-chip and so avoid increased demand on system memory bandwidth. By default this value is usually set to 0 and that is referred to as "single-sample" rendering. A value of 1 or greater is referred to as "multisample" rendering. <note>There are some semantic differences between single-sample rendering and multisampling with just 1 point sample such as it being redundant to use the cogl_framebuffer_resolve_samples() and cogl_framebuffer_resolve_samples_region() apis with single-sample rendering.</note> <note>It's recommended that cogl_framebuffer_resolve_samples_region() be explicitly used at the end of rendering to a point sample buffer to minimize the number of samples that get resolved. By default Cogl will implicitly resolve all framebuffer samples but if only a small region of a framebuffer has changed this can lead to redundant work being done.</note> A #CoglFramebuffer framebuffer The minimum number of samples per pixel Sets which stereo buffers should be drawn to. The default is %COGL_STEREO_BOTH, which means that both the left and right buffers will be affected by drawing. For this to have an effect, the display system must support stereo drawables, and the framebuffer must have been created with stereo enabled. (See cogl_onscreen_template_set_stereo_enabled(), cogl_framebuffer_get_is_stereo().) a pointer to a #CoglFramebuffer A #CoglStereoMode specifying which stereo buffers should be drawn tow. Defines a scale and offset for everything rendered relative to the top-left of the destination framebuffer. By default the viewport has an origin of (0,0) and width and height that match the framebuffer's size. Assuming a default projection and modelview matrix then you could translate the contents of a window down and right by leaving the viewport size unchanged by moving the offset to (10,10). The viewport coordinates are measured in pixels. If you left the x and y origin as (0,0) you could scale the windows contents down by specify and width and height that's half the real size of the framebuffer. <note>Although the function takes floating point arguments, existing drivers only allow the use of integer values. In the future floating point values will be exposed via a checkable feature.</note> A #CoglFramebuffer The top-left x coordinate of the viewport origin (only integers supported currently) The top-left y coordinate of the viewport origin (only integers supported currently) The width of the viewport (only integers supported currently) The height of the viewport (only integers supported currently) Multiplies the current model-view matrix by the given matrix. A #CoglFramebuffer pointer the matrix to multiply with the current model-view Multiplies the current model-view matrix by one that translates the model along all three axes according to the given values. A #CoglFramebuffer pointer Distance to translate along the x-axis Distance to translate along the y-axis Distance to translate along the z-axis %TRUE if there were no error allocating the framebuffer, else %FALSE. A #CoglFramebuffer All the error values that might be returned by cogl_get_graphics_reset_status(). Each value's meaning corresponds to the similarly named value defined in the ARB_robustness and NV_robustness_video_memory_purge extensions. You should aim to use the smallest data type that gives you enough range, since it reduces the size of your index array and can help reduce the demand on memory bandwidth. Note that %COGL_INDICES_TYPE_UNSIGNED_INT is only supported if the %COGL_FEATURE_ID_UNSIGNED_INT_INDICES feature is available. This should always be available on OpenGL but on OpenGL ES it will only be available if the GL_OES_element_index_uint extension is advertized. Your indices are unsigned bytes Your indices are unsigned shorts Your indices are unsigned ints Increases the reference count of @object by 1 the @object, with its reference count increased a #CoglObject Drecreases the reference count of @object by 1; if the reference count reaches 0, the resources allocated by @object will be freed a #CoglObject Finds the user data previously associated with @object using the given @key. If no user data has been associated with @object for the given @key this function returns NULL. The user data previously associated with @object using the given @key; or %NULL if no associated data is found. The object with associated private data to query The address of a #CoglUserDataKey which provides a unique value with which to index the private data. Associates some private @user_data with a given #CoglObject. To later remove the association call cogl_object_set_user_data() with the same @key but NULL for the @user_data. The object to associate private data with The address of a #CoglUserDataKey which provides a unique value with which to index the private data. The data to associate with the given object, or %NULL to remove a previous association. A #CoglUserDataDestroyCallback to call if the object is destroyed or if the association is removed by later setting %NULL data for the same key. This creates an offscreen framebuffer object using the given @texture as the primary color buffer. It doesn't just initialize the contents of the offscreen buffer with the @texture; they are tightly bound so that drawing to the offscreen buffer effectively updates the contents of the given texture. You don't need to destroy the offscreen buffer before you can use the @texture again. <note>This api only works with low-level #CoglTexture types such as #CoglTexture2D and not with meta-texture types such as #CoglTexture2DSliced.</note> The storage for the framebuffer is actually allocated lazily so this function will never return %NULL to indicate a runtime error. This means it is still possible to configure the framebuffer before it is really allocated. Simple applications without full error handling can simply rely on Cogl to lazily allocate the storage of framebuffers but you should be aware that if Cogl encounters an error (such as running out of GPU memory) then your application will simply abort with an error message. If you need to be able to catch such exceptions at runtime then you can explicitly allocate your framebuffer when you have finished configuring it by calling cogl_framebuffer_allocate() and passing in a #GError argument to catch any exceptions. a newly instantiated #CoglOffscreen framebuffer. A #CoglTexture pointer Gets the current age of the buffer contents. This function allows applications to query the age of the current back buffer contents for a #CoglOnscreen as the number of frames elapsed since the contents were most recently defined. These age values exposes enough information to applications about how Cogl internally manages back buffers to allow applications to re-use the contents of old frames and minimize how much must be redrawn for the next frame. The back buffer contents can either be reported as invalid (has an age of 0) or it may be reported to be the same contents as from n frames prior to the current frame. The queried value remains valid until the next buffer swap. <note>One caveat is that under X11 the buffer age does not reflect changes to buffer contents caused by the window systems. X11 applications must track Expose events to determine what buffer regions need to additionally be repaired each frame.</note> The recommended way to take advantage of this buffer age api is to build up a circular buffer of length 3 for tracking damage regions over the last 3 frames and when starting a new frame look at the age of the buffer and combine the damage regions for the current frame with the damage regions of previous @age frames so you know everything that must be redrawn to update the old contents for the new frame. <note>If the system doesn't not support being able to track the age of back buffers then this function will always return 0 which implies that the contents are undefined.</note> <note>The %COGL_FEATURE_ID_BUFFER_AGE feature can optionally be explicitly checked to determine if Cogl is currently tracking the age of #CoglOnscreen back buffer contents. If this feature is missing then this function will always return 0.</note> The age of the buffer contents or 0 when the buffer contents are undefined. A #CoglOnscreen framebuffer Implementation for https://www.khronos.org/registry/EGL/extensions/KHR/EGL_KHR_partial_update.txt This immediately queues state to OpenGL that will be used for the next swap. This needs to be called every frame. The expected values are independent of any viewport transforms applied to the framebuffer. A #CoglOnscreen framebuffer An array of integer 4-tuples representing damaged rectangles as (x, y, width, height) tuples. The number of 4-tuples to be read from @rectangles Swaps the current back buffer being rendered too, to the front for display and provides information to any system compositor about what regions of the buffer have changed (damage) with respect to the last swapped buffer. This function has the same semantics as cogl_framebuffer_swap_buffers() except that it additionally allows applications to pass a list of damaged rectangles which may be passed on to a compositor so that it can minimize how much of the screen is redrawn in response to this applications newly swapped front buffer. For example if your application is only animating a small object in the corner of the screen and everything else is remaining static then it can help the compositor to know that only the bottom right corner of your newly swapped buffer has really changed with respect to your previously swapped front buffer. If @n_rectangles is 0 then the whole buffer will implicitly be reported as damaged as if cogl_onscreen_swap_buffers() had been called. This function also implicitly discards the contents of the color, depth and stencil buffers as if cogl_framebuffer_discard_buffers() were used. The significance of the discard is that you should not expect to be able to start a new frame that incrementally builds on the contents of the previous frame. If you want to perform incremental updates to older back buffers then please refer to the cogl_onscreen_get_buffer_age() api. Whenever possible it is recommended that applications use this function instead of cogl_onscreen_swap_buffers() to improve performance when running under a compositor. <note>It is highly recommended to use this API in conjunction with the cogl_onscreen_get_buffer_age() api so that your application can perform incremental rendering based on old back buffers.</note> A #CoglOnscreen framebuffer An array of integer 4-tuples representing damaged rectangles as (x, y, width, height) tuples. The number of 4-tuples to be read from @rectangles Swaps a region of the back buffer being rendered too, to the front for display. @rectangles represents the region as array of @n_rectangles each defined by 4 sequential (x, y, width, height) integers. This function also implicitly discards the contents of the color, depth and stencil buffers as if cogl_framebuffer_discard_buffers() were used. The significance of the discard is that you should not expect to be able to start a new frame that incrementally builds on the contents of the previous frame. A #CoglOnscreen framebuffer An array of integer 4-tuples representing rectangles as (x, y, width, height) tuples. The number of 4-tuples to be read from @rectangles Installs a @callback function that will be called whenever the window system has lost the contents of a region of the onscreen buffer and the application should redraw it to repair the buffer. For example this may happen in a window system without a compositor if a window that was previously covering up the onscreen window has been moved causing a region of the onscreen to be exposed. The @callback will be passed a #CoglOnscreenDirtyInfo struct which describes a rectangle containing the newly dirtied region. Note that this may be called multiple times to describe a non-rectangular region composed of multiple smaller rectangles. The dirty events are separate from %COGL_FRAME_EVENT_SYNC events so the application should also listen for this event before rendering the dirty region to ensure that the framebuffer is actually ready for rendering. a #CoglOnscreenDirtyClosure pointer that can be used to remove the callback and associated @user_data later. A #CoglOnscreen framebuffer A callback function to call for dirty events A private pointer to be passed to @callback An optional callback to destroy @user_data when the @callback is removed or @onscreen is freed. Installs a @callback function that will be called for significant events relating to the given @onscreen framebuffer. The @callback will be used to notify when the system compositor is ready for this application to render a new frame. In this case %COGL_FRAME_EVENT_SYNC will be passed as the event argument to the given @callback in addition to the #CoglFrameInfo corresponding to the frame being acknowledged by the compositor. The @callback will also be called to notify when the frame has ended. In this case %COGL_FRAME_EVENT_COMPLETE will be passed as the event argument to the given @callback in addition to the #CoglFrameInfo corresponding to the newly presented frame. The meaning of "ended" here simply means that no more timing information will be collected within the corresponding #CoglFrameInfo and so this is a good opportunity to analyse the given info. It does not necessarily mean that the GPU has finished rendering the corresponding frame. We highly recommend throttling your application according to %COGL_FRAME_EVENT_SYNC events so that your application can avoid wasting resources, drawing more frames than your system compositor can display. a #CoglFrameClosure pointer that can be used to remove the callback and associated @user_data later. A #CoglOnscreen framebuffer A callback function to call for frame events A private pointer to be passed to @callback An optional callback to destroy @user_data when the @callback is removed or @onscreen is freed. Gets the current age of the buffer contents. This function allows applications to query the age of the current back buffer contents for a #CoglOnscreen as the number of frames elapsed since the contents were most recently defined. These age values exposes enough information to applications about how Cogl internally manages back buffers to allow applications to re-use the contents of old frames and minimize how much must be redrawn for the next frame. The back buffer contents can either be reported as invalid (has an age of 0) or it may be reported to be the same contents as from n frames prior to the current frame. The queried value remains valid until the next buffer swap. <note>One caveat is that under X11 the buffer age does not reflect changes to buffer contents caused by the window systems. X11 applications must track Expose events to determine what buffer regions need to additionally be repaired each frame.</note> The recommended way to take advantage of this buffer age api is to build up a circular buffer of length 3 for tracking damage regions over the last 3 frames and when starting a new frame look at the age of the buffer and combine the damage regions for the current frame with the damage regions of previous @age frames so you know everything that must be redrawn to update the old contents for the new frame. <note>If the system doesn't not support being able to track the age of back buffers then this function will always return 0 which implies that the contents are undefined.</note> <note>The %COGL_FEATURE_ID_BUFFER_AGE feature can optionally be explicitly checked to determine if Cogl is currently tracking the age of #CoglOnscreen back buffer contents. If this feature is missing then this function will always return 0.</note> The age of the buffer contents or 0 when the buffer contents are undefined. A #CoglOnscreen framebuffer Gets the value of the framebuffers frame counter. This is a counter that increases by one each time cogl_onscreen_swap_buffers() or cogl_onscreen_swap_region() is called. the current frame counter value This requests to make @onscreen invisible to the user. Actually the precise semantics of this function depend on the window system currently in use, and if you don't have a multi-windowining system this function may in-fact do nothing. This function does not implicitly allocate the given @onscreen framebuffer before hiding it. <note>Since Cogl doesn't explicitly track the visibility status of onscreen framebuffers it won't try to avoid redundant window system requests e.g. to show an already visible window. This also means that it's acceptable to alternatively use native APIs to show and hide windows without confusing Cogl.</note> The onscreen framebuffer to make invisible Implementation for https://www.khronos.org/registry/EGL/extensions/KHR/EGL_KHR_partial_update.txt This immediately queues state to OpenGL that will be used for the next swap. This needs to be called every frame. The expected values are independent of any viewport transforms applied to the framebuffer. A #CoglOnscreen framebuffer An array of integer 4-tuples representing damaged rectangles as (x, y, width, height) tuples. The number of 4-tuples to be read from @rectangles Removes a callback and associated user data that were previously registered using cogl_onscreen_add_dirty_callback(). If a destroy callback was passed to cogl_onscreen_add_dirty_callback() to destroy the user data then this will also get called. A #CoglOnscreen A #CoglOnscreenDirtyClosure returned from cogl_onscreen_add_dirty_callback() Removes a callback and associated user data that were previously registered using cogl_onscreen_add_frame_callback(). If a destroy callback was passed to cogl_onscreen_add_frame_callback() to destroy the user data then this will get called. A #CoglOnscreen A #CoglFrameClosure returned from cogl_onscreen_add_frame_callback() This requests to make @onscreen visible to the user. Actually the precise semantics of this function depend on the window system currently in use, and if you don't have a multi-windowining system this function may in-fact do nothing. This function will implicitly allocate the given @onscreen framebuffer before showing it if it hasn't already been allocated. When using the Wayland winsys calling this will set the surface to a toplevel type which will make it appear. If the application wants to set a different type for the surface, it can avoid calling cogl_onscreen_show() and set its own type directly with the Wayland client API via cogl_wayland_onscreen_get_surface(). <note>Since Cogl doesn't explicitly track the visibility status of onscreen framebuffers it won't try to avoid redundant window system requests e.g. to show an already visible window. This also means that it's acceptable to alternatively use native APIs to show and hide windows without confusing Cogl.</note> The onscreen framebuffer to make visible Swaps the current back buffer being rendered too, to the front for display. This function also implicitly discards the contents of the color, depth and stencil buffers as if cogl_framebuffer_discard_buffers() were used. The significance of the discard is that you should not expect to be able to start a new frame that incrementally builds on the contents of the previous frame. <note>It is highly recommended that applications use cogl_onscreen_swap_buffers_with_damage() instead whenever possible and also use the cogl_onscreen_get_buffer_age() api so they can perform incremental updates to older buffers instead of having to render a full buffer for every frame.</note> A #CoglOnscreen framebuffer Swaps the current back buffer being rendered too, to the front for display and provides information to any system compositor about what regions of the buffer have changed (damage) with respect to the last swapped buffer. This function has the same semantics as cogl_framebuffer_swap_buffers() except that it additionally allows applications to pass a list of damaged rectangles which may be passed on to a compositor so that it can minimize how much of the screen is redrawn in response to this applications newly swapped front buffer. For example if your application is only animating a small object in the corner of the screen and everything else is remaining static then it can help the compositor to know that only the bottom right corner of your newly swapped buffer has really changed with respect to your previously swapped front buffer. If @n_rectangles is 0 then the whole buffer will implicitly be reported as damaged as if cogl_onscreen_swap_buffers() had been called. This function also implicitly discards the contents of the color, depth and stencil buffers as if cogl_framebuffer_discard_buffers() were used. The significance of the discard is that you should not expect to be able to start a new frame that incrementally builds on the contents of the previous frame. If you want to perform incremental updates to older back buffers then please refer to the cogl_onscreen_get_buffer_age() api. Whenever possible it is recommended that applications use this function instead of cogl_onscreen_swap_buffers() to improve performance when running under a compositor. <note>It is highly recommended to use this API in conjunction with the cogl_onscreen_get_buffer_age() api so that your application can perform incremental rendering based on old back buffers.</note> A #CoglOnscreen framebuffer An array of integer 4-tuples representing damaged rectangles as (x, y, width, height) tuples. The number of 4-tuples to be read from @rectangles Swaps a region of the back buffer being rendered too, to the front for display. @rectangles represents the region as array of @n_rectangles each defined by 4 sequential (x, y, width, height) integers. This function also implicitly discards the contents of the color, depth and stencil buffers as if cogl_framebuffer_discard_buffers() were used. The significance of the discard is that you should not expect to be able to start a new frame that incrementally builds on the contents of the previous frame. A #CoglOnscreen framebuffer An array of integer 4-tuples representing rectangles as (x, y, width, height) tuples. The number of 4-tuples to be read from @rectangles A #CoglOnscreen framebuffer An array of integer 4-tuples representing damaged rectangles as (x, y, width, height) tuples. The number of 4-tuples to be read from @rectangles A #CoglOnscreen framebuffer An array of integer 4-tuples representing rectangles as (x, y, width, height) tuples. The number of 4-tuples to be read from @rectangles A #CoglOnscreen framebuffer An array of integer 4-tuples representing damaged rectangles as (x, y, width, height) tuples. The number of 4-tuples to be read from @rectangles The age of the buffer contents or 0 when the buffer contents are undefined. A #CoglOnscreen framebuffer Is a callback that can be registered via cogl_onscreen_add_dirty_callback() to be called when the windowing system determines that a region of the onscreen window has been lost and the application should redraw it. The onscreen that the frame is associated with A #CoglOnscreenDirtyInfo struct containing the details of the dirty area The user pointer passed to cogl_onscreen_add_frame_callback() An opaque type that tracks a #CoglOnscreenDirtyCallback and associated user data. A #CoglOnscreenDirtyClosure pointer will be returned from cogl_onscreen_add_dirty_callback() and it allows you to remove a callback later using cogl_onscreen_remove_dirty_callback(). A structure passed to callbacks registered using cogl_onscreen_add_dirty_callback(). The members describe a rectangle within the onscreen buffer that should be redrawn. Left edge of the dirty rectangle Top edge of the dirty rectangle, measured from the top of the window Width of the dirty rectangle Height of the dirty rectangle The maximum number of planes of a pixel format (see also cogl_pixel_format_get_planes()). Allocates and initializes a default simple pipeline that will color a primitive white. a pointer to a new #CoglPipeline a #CoglContext Adds a shader snippet that will hook on to the given layer of the pipeline. The exact part of the pipeline that the snippet wraps around depends on the hook that is given to cogl_snippet_new(). Note that some hooks can't be used with a layer and need to be added with cogl_pipeline_add_snippet() instead. A #CoglPipeline The layer to hook the snippet to A #CoglSnippet Adds a shader snippet to @pipeline. The snippet will wrap around or replace some part of the pipeline as defined by the hook point in @snippet. Note that some hook points are specific to a layer and must be added with cogl_pipeline_add_layer_snippet() instead. A #CoglPipeline The #CoglSnippet to add to the vertex processing hook Creates a new pipeline with the configuration copied from the source pipeline. We would strongly advise developers to always aim to use cogl_pipeline_copy() instead of cogl_pipeline_new() whenever there will be any similarity between two pipelines. Copying a pipeline helps Cogl keep track of a pipelines ancestry which we may use to help minimize GPU state changes. a pointer to the newly allocated #CoglPipeline a #CoglPipeline object to copy Iterates all the layer indices of the given @pipeline. A #CoglPipeline object A #CoglPipelineLayerCallback to be called for each layer index Private data that will be passed to the callback The alpha test function of @pipeline. A #CoglPipeline object The alpha test reference value of @pipeline. A #CoglPipeline object Retrieves the current pipeline color. A #CoglPipeline object The location to store the color the cull face mode that was previously set with cogl_pipeline_set_cull_face_mode(). Retrieves the current depth state configuration for the given @pipeline as previously set using cogl_pipeline_set_depth_state(). A #CoglPipeline object A destination #CoglDepthState struct The order of the vertices within a primitive specifies whether it is considered to be front or back facing. This function specifies which order is considered to be the front faces. %COGL_WINDING_COUNTER_CLOCKWISE sets the front faces to primitives with vertices in a counter-clockwise order and %COGL_WINDING_CLOCKWISE sets them to be clockwise. The default is %COGL_WINDING_COUNTER_CLOCKWISE. The @pipeline front face winding a #CoglPipeline Returns the decimation and interpolation filters used when a texture is drawn at other scales than 100%. A #CoglPipeline object the layer number to change. Return location for the filter used when scaling a texture down. Return location for the filter used when magnifying a texture. Gets whether point sprite coordinate generation is enabled for this texture layer. whether the texture coordinates will be replaced with point sprite coordinates. A #CoglPipeline object the layer number to check. the texture that was set for the given layer of the pipeline or %NULL if no texture was set. A #CoglPipeline object the index of the layer Returns the wrap mode for the 's' coordinate of texture lookups on this layer. the wrap mode for the 's' coordinate of texture lookups on this layer. A #CoglPipeline object the layer number to change. Returns the wrap mode for the 't' coordinate of texture lookups on this layer. the wrap mode for the 't' coordinate of texture lookups on this layer. A #CoglPipeline object the layer number to change. Retrieves the number of layers defined for the given @pipeline the number of layers A #CoglPipeline object %TRUE if the pipeline has per-vertex point size enabled or %FALSE otherwise. The per-vertex point size can be enabled with cogl_pipeline_set_per_vertex_point_size(). a #CoglPipeline pointer Get the size of points drawn when %COGL_VERTICES_MODE_POINTS is used with the vertex buffer API. the point size of the @pipeline. a #CoglPipeline pointer This is used to get an integer representing the uniform with the name @uniform_name. The integer can be passed to functions such as cogl_pipeline_set_uniform_1f() to set the value of a uniform. This function will always return a valid integer. Ie, unlike OpenGL, it does not return -1 if the uniform is not available in this pipeline so it can not be used to test whether uniforms are present. It is not necessary to set the program on the pipeline before calling this function. A integer representing the location of the given uniform. A #CoglPipeline object The name of a uniform Queries what user program has been associated with the given @pipeline using cogl_pipeline_set_user_program(). The current user program or %NULL. a #CoglPipeline object. This function removes a layer from your pipeline A #CoglPipeline object Specifies the layer you want to remove Before a primitive is blended with the framebuffer, it goes through an alpha test stage which lets you discard fragments based on the current alpha value. This function lets you change the function used to evaluate the alpha channel, and thus determine which fragments are discarded and which continue on to the blending stage. The default is %COGL_PIPELINE_ALPHA_FUNC_ALWAYS A #CoglPipeline object A @CoglPipelineAlphaFunc constant A reference point that the chosen alpha function uses to compare incoming fragments to. If not already familiar; please refer <link linkend="cogl-Blend-Strings">here</link> for an overview of what blend strings are, and their syntax. Blending occurs after the alpha test function, and combines fragments with the framebuffer. Currently the only blend function Cogl exposes is ADD(). So any valid blend statements will be of the form: |[ &lt;channel-mask&gt;=ADD(SRC_COLOR*(&lt;factor&gt;), DST_COLOR*(&lt;factor&gt;)) ]| This is the list of source-names usable as blend factors: <itemizedlist> <listitem><para>SRC_COLOR: The color of the incoming fragment</para></listitem> <listitem><para>DST_COLOR: The color of the framebuffer</para></listitem> <listitem><para>CONSTANT: The constant set via cogl_pipeline_set_blend_constant()</para></listitem> </itemizedlist> The source names can be used according to the <link linkend="cogl-Blend-String-syntax">color-source and factor syntax</link>, so for example "(1-SRC_COLOR[A])" would be a valid factor, as would "(CONSTANT[RGB])" These can also be used as factors: <itemizedlist> <listitem>0: (0, 0, 0, 0)</listitem> <listitem>1: (1, 1, 1, 1)</listitem> <listitem>SRC_ALPHA_SATURATE_FACTOR: (f,f,f,1) where f = MIN(SRC_COLOR[A],1-DST_COLOR[A])</listitem> </itemizedlist> <note>Remember; all color components are normalized to the range [0, 1] before computing the result of blending.</note> <example id="cogl-Blend-Strings-blend-unpremul"> <title>Blend Strings/1</title> <para>Blend a non-premultiplied source over a destination with premultiplied alpha:</para> <programlisting> "RGB = ADD(SRC_COLOR*(SRC_COLOR[A]), DST_COLOR*(1-SRC_COLOR[A]))" "A = ADD(SRC_COLOR, DST_COLOR*(1-SRC_COLOR[A]))" </programlisting> </example> <example id="cogl-Blend-Strings-blend-premul"> <title>Blend Strings/2</title> <para>Blend a premultiplied source over a destination with premultiplied alpha</para> <programlisting> "RGBA = ADD(SRC_COLOR, DST_COLOR*(1-SRC_COLOR[A]))" </programlisting> </example> The default blend string is: |[ RGBA = ADD (SRC_COLOR, DST_COLOR*(1-SRC_COLOR[A])) ]| That gives normal alpha-blending when the calculated color for the pipeline is in premultiplied form. %TRUE if the blend string was successfully parsed, and the described blending is supported by the underlying driver/hardware. If there was an error, %FALSE is returned and @error is set accordingly (if present). A #CoglPipeline object A <link linkend="cogl-Blend-Strings">Cogl blend string</link> describing the desired blend function. When blending is setup to reference a CONSTANT blend factor then blending will depend on the constant set with this function. A #CoglPipeline object The constant color you want Sets the basic color of the pipeline, used when no lighting is enabled. Note that if you don't add any layers to the pipeline then the color will be blended unmodified with the destination; the default blend expects premultiplied colors: for example, use (0.5, 0.0, 0.0, 0.5) for semi-transparent red. See cogl_color_premultiply(). The default value is (1.0, 1.0, 1.0, 1.0) A #CoglPipeline object The components of the color Sets the basic color of the pipeline, used when no lighting is enabled. The default value is (1.0, 1.0, 1.0, 1.0) A #CoglPipeline object The red component The green component The blue component The alpha component Sets the basic color of the pipeline, used when no lighting is enabled. The default value is (0xff, 0xff, 0xff, 0xff) A #CoglPipeline object The red component The green component The blue component The alpha component Sets which faces will be culled when drawing. Face culling can be used to increase efficiency by avoiding drawing faces that would get overridden. For example, if a model has gaps so that it is impossible to see the inside then faces which are facing away from the screen will never be seen so there is no point in drawing them. This can be achieved by setting the cull face mode to %COGL_PIPELINE_CULL_FACE_MODE_BACK. Face culling relies on the primitives being drawn with a specific order to represent which faces are facing inside and outside the model. This order can be specified by calling cogl_pipeline_set_front_face_winding(). A #CoglPipeline The new mode to set This commits all the depth state configured in @state struct to the given @pipeline. The configuration values are copied into the pipeline so there is no requirement to keep the #CoglDepthState struct around if you don't need it any more. Note: Since some platforms do not support the depth range feature it is possible for this function to fail and report an @error. TRUE if the GPU supports all the given @state else %FALSE and returns an @error. A #CoglPipeline object A #CoglDepthState struct The order of the vertices within a primitive specifies whether it is considered to be front or back facing. This function specifies which order is considered to be the front faces. %COGL_WINDING_COUNTER_CLOCKWISE sets the front faces to primitives with vertices in a counter-clockwise order and %COGL_WINDING_CLOCKWISE sets them to be clockwise. The default is %COGL_WINDING_COUNTER_CLOCKWISE. a #CoglPipeline the winding order If not already familiar; you can refer <link linkend="cogl-Blend-Strings">here</link> for an overview of what blend strings are and there syntax. These are all the functions available for texture combining: <itemizedlist> <listitem>REPLACE(arg0) = arg0</listitem> <listitem>MODULATE(arg0, arg1) = arg0 x arg1</listitem> <listitem>ADD(arg0, arg1) = arg0 + arg1</listitem> <listitem>ADD_SIGNED(arg0, arg1) = arg0 + arg1 - 0.5</listitem> <listitem>INTERPOLATE(arg0, arg1, arg2) = arg0 x arg2 + arg1 x (1 - arg2)</listitem> <listitem>SUBTRACT(arg0, arg1) = arg0 - arg1</listitem> <listitem> <programlisting> DOT3_RGB(arg0, arg1) = 4 x ((arg0[R] - 0.5)) * (arg1[R] - 0.5) + (arg0[G] - 0.5)) * (arg1[G] - 0.5) + (arg0[B] - 0.5)) * (arg1[B] - 0.5)) </programlisting> </listitem> <listitem> <programlisting> DOT3_RGBA(arg0, arg1) = 4 x ((arg0[R] - 0.5)) * (arg1[R] - 0.5) + (arg0[G] - 0.5)) * (arg1[G] - 0.5) + (arg0[B] - 0.5)) * (arg1[B] - 0.5)) </programlisting> </listitem> </itemizedlist> Refer to the <link linkend="cogl-Blend-String-syntax">color-source syntax</link> for describing the arguments. The valid source names for texture combining are: <variablelist> <varlistentry> <term>TEXTURE</term> <listitem>Use the color from the current texture layer</listitem> </varlistentry> <varlistentry> <term>TEXTURE_0, TEXTURE_1, etc</term> <listitem>Use the color from the specified texture layer</listitem> </varlistentry> <varlistentry> <term>CONSTANT</term> <listitem>Use the color from the constant given with cogl_pipeline_set_layer_combine_constant()</listitem> </varlistentry> <varlistentry> <term>PRIMARY</term> <listitem>Use the color of the pipeline as set with cogl_pipeline_set_color()</listitem> </varlistentry> <varlistentry> <term>PREVIOUS</term> <listitem>Either use the texture color from the previous layer, or if this is layer 0, use the color of the pipeline as set with cogl_pipeline_set_color()</listitem> </varlistentry> </variablelist> <refsect2 id="cogl-Layer-Combine-Examples"> <title>Layer Combine Examples</title> <para>This is effectively what the default blending is:</para> <informalexample><programlisting> RGBA = MODULATE (PREVIOUS, TEXTURE) </programlisting></informalexample> <para>This could be used to cross-fade between two images, using the alpha component of a constant as the interpolator. The constant color is given by calling cogl_pipeline_set_layer_combine_constant().</para> <informalexample><programlisting> RGBA = INTERPOLATE (PREVIOUS, TEXTURE, CONSTANT[A]) </programlisting></informalexample> </refsect2> <note>You can't give a multiplication factor for arguments as you can with blending.</note> %TRUE if the blend string was successfully parsed, and the described texture combining is supported by the underlying driver and or hardware. On failure, %FALSE is returned and @error is set A #CoglPipeline object Specifies the layer you want define a combine function for A <link linkend="cogl-Blend-Strings">Cogl blend string</link> describing the desired texture combine function. When you are using the 'CONSTANT' color source in a layer combine description then you can use this function to define its value. A #CoglPipeline object Specifies the layer you want to specify a constant used for texture combining The constant color you want Changes the decimation and interpolation filters used when a texture is drawn at other scales than 100%. <note>It is an error to pass anything other than %COGL_PIPELINE_FILTER_NEAREST or %COGL_PIPELINE_FILTER_LINEAR as magnification filters since magnification doesn't ever need to reference values stored in the mipmap chain.</note> A #CoglPipeline object the layer number to change. the filter used when scaling a texture down. the filter used when magnifying a texture. This function lets you set a matrix that can be used to e.g. translate and rotate a single layer of a pipeline used to fill your geometry. A #CoglPipeline object the index for the layer inside @pipeline the transformation matrix for the layer Sets the texture for this layer to be the default texture for the given type. The default texture is a 1x1 pixel white texture. This function is mostly useful if you want to create a base pipeline that you want to create multiple copies from using cogl_pipeline_copy(). In that case this function can be used to specify the texture type so that any pipeline copies can share the internal texture type state for efficiency. A #CoglPipeline The layer number to modify When rendering points, if @enable is %TRUE then the texture coordinates for this layer will be replaced with coordinates that vary from 0.0 to 1.0 across the primitive. The top left of the point will have the coordinates 0.0,0.0 and the bottom right will have 1.0,1.0. If @enable is %FALSE then the coordinates will be fixed for the entire point. %TRUE if the function succeeds, %FALSE otherwise. A #CoglPipeline object the layer number to change. whether to enable point sprite coord generation. Sets the wrap mode for all three coordinates of texture lookups on this layer. This is equivalent to calling cogl_pipeline_set_layer_wrap_mode_s() and cogl_pipeline_set_layer_wrap_mode_t() separately. A #CoglPipeline object the layer number to change. the new wrap mode Sets the wrap mode for the 's' coordinate of texture lookups on this layer. A #CoglPipeline object the layer number to change. the new wrap mode Sets the wrap mode for the 't' coordinate of texture lookups on this layer. A #CoglPipeline object the layer number to change. the new wrap mode Sets whether to use a per-vertex point size or to use the value set by cogl_pipeline_set_point_size(). If per-vertex point size is enabled then the point size can be set for an individual point either by drawing with a #CoglAttribute with the name ‘cogl_point_size_in’ or by writing to the GLSL builtin ‘cogl_point_size_out’ from a vertex shader snippet. If per-vertex point size is enabled and this attribute is not used and cogl_point_size_out is not written to then the results are undefined. %TRUE if the change succeeded or %FALSE otherwise a #CoglPipeline pointer whether to enable per-vertex point size Changes the size of points drawn when %COGL_VERTICES_MODE_POINTS is used with the attribute buffer API. Note that typically the GPU will only support a limited minimum and maximum range of point sizes. If the chosen point size is outside that range then the nearest value within that range will be used instead. The size of a point is in screen space so it will be the same regardless of any transformations. If the point size is set to 0.0 then drawing points with the pipeline will have undefined results. This is the default value so if an application wants to draw points it must make sure to use a pipeline that has an explicit point size set on it. a #CoglPipeline pointer the new point size. Sets a new value for the uniform at @uniform_location. If this pipeline has a user program attached and is later used as a source for drawing, the given value will be assigned to the uniform which can be accessed from the shader's source. The value for @uniform_location should be retrieved from the string name of the uniform by calling cogl_pipeline_get_uniform_location(). This function should be used to set uniforms that are of type float. It can also be used to set a single member of a float array uniform. A #CoglPipeline object The uniform's location identifier The new value for the uniform Sets a new value for the uniform at @uniform_location. If this pipeline has a user program attached and is later used as a source for drawing, the given value will be assigned to the uniform which can be accessed from the shader's source. The value for @uniform_location should be retrieved from the string name of the uniform by calling cogl_pipeline_get_uniform_location(). This function should be used to set uniforms that are of type int. It can also be used to set a single member of a int array uniform or a sampler uniform. A #CoglPipeline object The uniform's location identifier The new value for the uniform Sets new values for the uniform at @uniform_location. If this pipeline has a user program attached and is later used as a source for drawing, the given values will be assigned to the uniform which can be accessed from the shader's source. The value for @uniform_location should be retrieved from the string name of the uniform by calling cogl_pipeline_get_uniform_location(). This function can be used to set any floating point type uniform, including float arrays and float vectors. For example, to set a single vec4 uniform you would use 4 for @n_components and 1 for @count. To set an array of 8 float values, you could use 1 for @n_components and 8 for @count. A #CoglPipeline object The uniform's location identifier The number of components in the corresponding uniform's type The number of values to set Pointer to the new values to set Sets new values for the uniform at @uniform_location. If this pipeline has a user program attached and is later used as a source for drawing, the given values will be assigned to the uniform which can be accessed from the shader's source. The value for @uniform_location should be retrieved from the string name of the uniform by calling cogl_pipeline_get_uniform_location(). This function can be used to set any integer type uniform, including int arrays and int vectors. For example, to set a single ivec4 uniform you would use 4 for @n_components and 1 for @count. To set an array of 8 int values, you could use 1 for @n_components and 8 for @count. A #CoglPipeline object The uniform's location identifier The number of components in the corresponding uniform's type The number of values to set Pointer to the new values to set Sets new values for the uniform at @uniform_location. If this pipeline has a user program attached and is later used as a source for drawing, the given values will be assigned to the uniform which can be accessed from the shader's source. The value for @uniform_location should be retrieved from the string name of the uniform by calling cogl_pipeline_get_uniform_location(). This function can be used to set any matrix type uniform, including matrix arrays. For example, to set a single mat4 uniform you would use 4 for @dimensions and 1 for @count. To set an array of 8 mat3 values, you could use 3 for @dimensions and 8 for @count. If @transpose is %FALSE then the matrix is expected to be in column-major order or if it is %TRUE then the matrix is in row-major order. You can pass a #graphene_matrix_t by calling by passing the result of graphene_matrix_to_float() in @value and setting @transpose to %FALSE. A #CoglPipeline object The uniform's location identifier The size of the matrix The number of values to set Whether to transpose the matrix Pointer to the new values to set Associates a linked CoglProgram with the given pipeline so that the program can take full control of vertex and/or fragment processing. This is an example of how it can be used to associate an ARBfp program with a #CoglPipeline: |[ CoglHandle shader; CoglHandle program; CoglPipeline *pipeline; shader = cogl_create_shader (COGL_SHADER_TYPE_FRAGMENT); cogl_shader_source (shader, "!!ARBfp1.0\n" "MOV result.color,fragment.color;\n" "END\n"); program = cogl_create_program (); cogl_program_attach_shader (program, shader); cogl_program_link (program); pipeline = cogl_pipeline_new (); cogl_pipeline_set_user_program (pipeline, program); cogl_set_source_color4ub (0xff, 0x00, 0x00, 0xff); cogl_rectangle (0, 0, 100, 100); ]| It is possibly worth keeping in mind that this API is not part of the long term design for how we want to expose shaders to Cogl developers (We are planning on deprecating the cogl_program and cogl_shader APIs in favour of a "snippet" framework) but in the meantime we hope this will handle most practical GLSL and ARBfp requirements. a #CoglPipeline object. A #CoglHandle to a linked CoglProgram Alpha testing happens before blending primitives with the framebuffer and gives an opportunity to discard fragments based on a comparison with the incoming alpha value and a reference alpha value. The #CoglPipelineAlphaFunc determines how the comparison is done. Never let the fragment through. Let the fragment through if the incoming alpha value is less than the reference alpha value Let the fragment through if the incoming alpha value equals the reference alpha value Let the fragment through if the incoming alpha value is less than or equal to the reference alpha value Let the fragment through if the incoming alpha value is greater than the reference alpha value Let the fragment through if the incoming alpha value does not equal the reference alpha value Let the fragment through if the incoming alpha value is greater than or equal to the reference alpha value. Always let the fragment through. Specifies which faces should be culled. This can be set on a pipeline using cogl_pipeline_set_cull_face_mode(). Neither face will be culled. This is the default. Front faces will be culled. Back faces will be culled. All faces will be culled. Texture filtering is used whenever the current pixel maps either to more than one texture element (texel) or less than one. These filter enums correspond to different strategies used to come up with a pixel color, by possibly referring to multiple neighbouring texels and taking a weighted average or simply using the nearest texel. Measuring in manhatten distance from the, current pixel center, use the nearest texture texel Use the weighted average of the 4 texels nearest the current pixel center Select the mimap level whose texel size most closely matches the current pixel, and use the %COGL_PIPELINE_FILTER_NEAREST criterion Select the mimap level whose texel size most closely matches the current pixel, and use the %COGL_PIPELINE_FILTER_LINEAR criterion Select the two mimap levels whose texel size most closely matches the current pixel, use the %COGL_PIPELINE_FILTER_NEAREST criterion on each one and take their weighted average Select the two mimap levels whose texel size most closely matches the current pixel, use the %COGL_PIPELINE_FILTER_LINEAR criterion on each one and take their weighted average The callback prototype used with cogl_pipeline_foreach_layer() for iterating all the layers of a @pipeline. The #CoglPipeline whose layers are being iterated The current layer index The private data passed to cogl_pipeline_foreach_layer() The wrap mode specifies what happens when texture coordinates outside the range 0→1 are used. Note that if the filter mode is anything but %COGL_PIPELINE_FILTER_NEAREST then texels outside the range 0→1 might be used even when the coordinate is exactly 0 or 1 because OpenGL will try to sample neighbouring pixels. For example if you are trying to render the full texture then you may get artifacts around the edges when the pixels from the other side are merged in if the wrap mode is set to repeat. The texture will be repeated. This is useful for example to draw a tiled background. The coordinates outside the range 0→1 will sample copies of the edge pixels of the texture. This is useful to avoid artifacts if only one copy of the texture is being rendered. Cogl will try to automatically decide which of the above two to use. For cogl_rectangle(), it will use repeat mode if any of the texture coordinates are outside the range 0→1, otherwise it will use clamp to edge. For cogl_polygon() it will always use repeat mode. For cogl_vertex_buffer_draw() it will use repeat mode except for layers that have point sprite coordinate generation enabled. This is the default value. Pixel formats used by Cogl. For the formats with a byte per component, the order of the components specify the order in increasing memory addresses. So for example %COGL_PIXEL_FORMAT_RGB_888 would have the red component in the lowest address, green in the next address and blue after that regardless of the endianness of the system. For the formats with non byte aligned components the component order specifies the order within a 16-bit or 32-bit number from most significant bit to least significant. So for %COGL_PIXEL_FORMAT_RGB_565, the red component would be in bits 11-15, the green component would be in 6-11 and the blue component would be in 1-5. Therefore the order in memory depends on the endianness of the system. When uploading a texture %COGL_PIXEL_FORMAT_ANY can be used as the internal format. Cogl will try to pick the best format to use internally and convert the texture data if necessary. Any format 8 bits alpha mask RGB, 16 bits RGBA, 16 bits RGBA, 16 bits Not currently supported Single luminance component RG, 16 bits. Note that red-green textures are only available if %COGL_FEATURE_ID_TEXTURE_RG is advertised. See cogl_texture_set_components() for details. RGB, 24 bits BGR, 24 bits RGBA, 32 bits BGRA, 32 bits ARGB, 32 bits ABGR, 32 bits RGBA, 32 bits, 10 bpc BGRA, 32 bits, 10 bpc ARGB, 32 bits, 10 bpc ABGR, 32 bits, 10 bpc RGBA half floating point, 64 bit BGRA half floating point, 64 bit ARGB half floating point, 64 bit ABGR half floating point, 64 bit Premultiplied RGBA, 32 bits Premultiplied BGRA, 32 bits Premultiplied ARGB, 32 bits Premultiplied ABGR, 32 bits Premultiplied RGBA, 16 bits Premultiplied RGBA, 16 bits Premultiplied RGBA, 32 bits, 10 bpc Premultiplied BGRA, 32 bits, 10 bpc Premultiplied ARGB, 32 bits, 10 bpc Premultiplied ABGR, 32 bits, 10 bpc Premultiplied RGBA half floating point, 64 bit Premultiplied BGRA half floating point, 64 bit Premultiplied ARGB half floating point, 64 bit Premultiplied ABGR half floating point, 64 bit Flags for cogl_framebuffer_read_pixels_into_bitmap() Read from the color buffer Types of shaders A program for processing vertices A program for processing fragments Allocates and initializes a new snippet with the given source strings. a pointer to a new #CoglSnippet The point in the pipeline that this snippet will wrap around or replace. The source code for the declarations for this snippet or %NULL. See cogl_snippet_set_declarations(). The source code to run after the hook point where this shader snippet is attached or %NULL. See cogl_snippet_set_post(). the source string that was set with cogl_snippet_set_declarations() or %NULL if none was set. A #CoglSnippet the hook that was set when cogl_snippet_new() was called. A #CoglSnippet the source string that was set with cogl_snippet_set_post() or %NULL if none was set. A #CoglSnippet the source string that was set with cogl_snippet_set_pre() or %NULL if none was set. A #CoglSnippet the source string that was set with cogl_snippet_set_replace() or %NULL if none was set. A #CoglSnippet Sets a source string that will be inserted in the global scope of the generated shader when this snippet is used on a pipeline. This string is typically used to declare uniforms, attributes or functions that will be used by the other parts of the snippets. This function should only be called before the snippet is attached to its first pipeline. After that the snippet should be considered immutable. A #CoglSnippet The new source string for the declarations section of this snippet. Sets a source string that will be inserted after the hook point in the generated shader for the pipeline that this snippet is attached to. Please see the documentation of each hook point in #CoglPipeline for a description of how this string should be used. This function should only be called before the snippet is attached to its first pipeline. After that the snippet should be considered immutable. A #CoglSnippet The new source string for the post section of this snippet. Sets a source string that will be inserted before the hook point in the generated shader for the pipeline that this snippet is attached to. Please see the documentation of each hook point in #CoglPipeline for a description of how this string should be used. This function should only be called before the snippet is attached to its first pipeline. After that the snippet should be considered immutable. A #CoglSnippet The new source string for the pre section of this snippet. Sets a source string that will be used instead of any generated source code or any previous snippets for this hook point. Please see the documentation of each hook point in #CoglPipeline for a description of how this string should be used. This function should only be called before the snippet is attached to its first pipeline. After that the snippet should be considered immutable. A #CoglSnippet The new source string for the replace section of this snippet. #CoglSnippetHook is used to specify a location within a #CoglPipeline where the code of the snippet should be used when it is attached to a pipeline. <glosslist> <glossentry> <glossterm>%COGL_SNIPPET_HOOK_VERTEX_GLOBALS</glossterm> <glossdef> <para> Adds a shader snippet at the beginning of the global section of the shader for the vertex processing. Any declarations here can be shared with all other snippets that are attached to a vertex hook. Only the ‘declarations’ string is used and the other strings are ignored. </para> </glossdef> </glossentry> <glossentry> <glossterm>%COGL_SNIPPET_HOOK_FRAGMENT_GLOBALS</glossterm> <glossdef> <para> Adds a shader snippet at the beginning of the global section of the shader for the fragment processing. Any declarations here can be shared with all other snippets that are attached to a fragment hook. Only the ‘declarations’ string is used and the other strings are ignored. </para> </glossdef> </glossentry> <glossentry> <glossterm>%COGL_SNIPPET_HOOK_VERTEX</glossterm> <glossdef> <para> Adds a shader snippet that will hook on to the vertex processing stage of the pipeline. This gives a chance for the application to modify the vertex attributes generated by the shader. Typically the snippet will modify cogl_color_out or cogl_position_out builtins. </para> <para> The ‘declarations’ string in @snippet will be inserted in the global scope of the shader. Use this to declare any uniforms, attributes or functions that the snippet requires. </para> <para> The ‘pre’ string in @snippet will be inserted at the top of the main() function before any vertex processing is done. </para> <para> The ‘replace’ string in @snippet will be used instead of the generated vertex processing if it is present. This can be used if the application wants to provide a complete vertex shader and doesn't need the generated output from Cogl. </para> <para> The ‘post’ string in @snippet will be inserted after all of the standard vertex processing is done. This can be used to modify the outputs. </para> </glossdef> </glossentry> <glossentry> <glossterm>%COGL_SNIPPET_HOOK_VERTEX_TRANSFORM</glossterm> <glossdef> <para> Adds a shader snippet that will hook on to the vertex transform stage. Typically the snippet will use the cogl_modelview_matrix, cogl_projection_matrix and cogl_modelview_projection_matrix matrices and the cogl_position_in attribute. The hook must write to cogl_position_out. The default processing for this hook will multiply cogl_position_in by the combined modelview-projection matrix and store it on cogl_position_out. </para> <para> The ‘declarations’ string in @snippet will be inserted in the global scope of the shader. Use this to declare any uniforms, attributes or functions that the snippet requires. </para> <para> The ‘pre’ string in @snippet will be inserted at the top of the main() function before the vertex transform is done. </para> <para> The ‘replace’ string in @snippet will be used instead of the generated vertex transform if it is present. </para> <para> The ‘post’ string in @snippet will be inserted after all of the standard vertex transformation is done. This can be used to modify the cogl_position_out in addition to the default processing. </para> </glossdef> </glossentry> <glossentry> <glossterm>%COGL_SNIPPET_HOOK_POINT_SIZE</glossterm> <glossdef> <para> Adds a shader snippet that will hook on to the point size calculation step within the vertex shader stage. The snippet should write to the builtin cogl_point_size_out with the new point size. The snippet can either read cogl_point_size_in directly and write a new value or first read an existing value in cogl_point_size_out that would be set by a previous snippet. Note that this hook is only used if cogl_pipeline_set_per_vertex_point_size() is enabled on the pipeline. </para> <para> The ‘declarations’ string in @snippet will be inserted in the global scope of the shader. Use this to declare any uniforms, attributes or functions that the snippet requires. </para> <para> The ‘pre’ string in @snippet will be inserted just before calculating the point size. </para> <para> The ‘replace’ string in @snippet will be used instead of the generated point size calculation if it is present. </para> <para> The ‘post’ string in @snippet will be inserted after the standard point size calculation is done. This can be used to modify cogl_point_size_out in addition to the default processing. </para> </glossdef> </glossentry> <glossentry> <glossterm>%COGL_SNIPPET_HOOK_FRAGMENT</glossterm> <glossdef> <para> Adds a shader snippet that will hook on to the fragment processing stage of the pipeline. This gives a chance for the application to modify the fragment color generated by the shader. Typically the snippet will modify cogl_color_out. </para> <para> The ‘declarations’ string in @snippet will be inserted in the global scope of the shader. Use this to declare any uniforms, attributes or functions that the snippet requires. </para> <para> The ‘pre’ string in @snippet will be inserted at the top of the main() function before any fragment processing is done. </para> <para> The ‘replace’ string in @snippet will be used instead of the generated fragment processing if it is present. This can be used if the application wants to provide a complete fragment shader and doesn't need the generated output from Cogl. </para> <para> The ‘post’ string in @snippet will be inserted after all of the standard fragment processing is done. At this point the generated value for the rest of the pipeline state will already be in cogl_color_out so the application can modify the result by altering this variable. </para> </glossdef> </glossentry> <glossentry> <glossterm>%COGL_SNIPPET_HOOK_TEXTURE_COORD_TRANSFORM</glossterm> <glossdef> <para> Adds a shader snippet that will hook on to the texture coordinate transformation of a particular layer. This can be used to replace the processing for a layer or to modify the results. </para> <para> Within the snippet code for this hook there are two extra variables. The first is a mat4 called cogl_matrix which represents the user matrix for this layer. The second is called cogl_tex_coord and represents the incoming and outgoing texture coordinate. On entry to the hook, cogl_tex_coord contains the value of the corresponding texture coordinate attribute for this layer. The hook is expected to modify this variable. The output will be passed as a varying to the fragment processing stage. The default code will just multiply cogl_matrix by cogl_tex_coord and store the result in cogl_tex_coord. </para> <para> The ‘declarations’ string in @snippet will be inserted in the global scope of the shader. Use this to declare any uniforms, attributes or functions that the snippet requires. </para> <para> The ‘pre’ string in @snippet will be inserted just before the fragment processing for this layer. At this point cogl_tex_coord still contains the value of the texture coordinate attribute. </para> <para> If a ‘replace’ string is given then this will be used instead of the default fragment processing for this layer. The snippet can modify cogl_tex_coord or leave it as is to apply no transformation. </para> <para> The ‘post’ string in @snippet will be inserted just after the transformation. At this point cogl_tex_coord will contain the results of the transformation but it can be further modified by the snippet. </para> </glossdef> </glossentry> <glossentry> <glossterm>%COGL_SNIPPET_HOOK_LAYER_FRAGMENT</glossterm> <glossdef> <para> Adds a shader snippet that will hook on to the fragment processing of a particular layer. This can be used to replace the processing for a layer or to modify the results. </para> <para> Within the snippet code for this hook there is an extra vec4 variable called ‘cogl_layer’. This contains the resulting color that will be used for the layer. This can be modified in the ‘post’ section or it the default processing can be replaced entirely using the ‘replace’ section. </para> <para> The ‘declarations’ string in @snippet will be inserted in the global scope of the shader. Use this to declare any uniforms, attributes or functions that the snippet requires. </para> <para> The ‘pre’ string in @snippet will be inserted just before the fragment processing for this layer. </para> <para> If a ‘replace’ string is given then this will be used instead of the default fragment processing for this layer. The snippet must write to the ‘cogl_layer’ variable in that case. </para> <para> The ‘post’ string in @snippet will be inserted just after the fragment processing for the layer. The results can be modified by changing the value of the ‘cogl_layer’ variable. </para> </glossdef> </glossentry> <glossentry> <glossterm>%COGL_SNIPPET_HOOK_TEXTURE_LOOKUP</glossterm> <glossdef> <para> Adds a shader snippet that will hook on to the texture lookup part of a given layer. This gives a chance for the application to modify the coordinates that will be used for the texture lookup or to alter the returned texel. </para> <para> Within the snippet code for this hook there are three extra variables available. ‘cogl_sampler’ is a sampler object representing the sampler for the layer where the snippet is attached. ‘cogl_tex_coord’ is a vec4 which contains the texture coordinates that will be used for the texture lookup. This can be modified. ‘cogl_texel’ will contain the result of the texture lookup. This can also be modified. </para> <para> The ‘declarations’ string in @snippet will be inserted in the global scope of the shader. Use this to declare any uniforms, attributes or functions that the snippet requires. </para> <para> The ‘pre’ string in @snippet will be inserted at the top of the main() function before any fragment processing is done. This is a good place to modify the cogl_tex_coord variable. </para> <para> If a ‘replace’ string is given then this will be used instead of a the default texture lookup. The snippet would typically use its own sampler in this case. </para> <para> The ‘post’ string in @snippet will be inserted after texture lookup has been performed. Here the snippet can modify the cogl_texel variable to alter the returned texel. </para> </glossdef> </glossentry> </glosslist> A hook for the entire vertex processing stage of the pipeline. A hook for the vertex transformation. A hook for declaring global data that can be shared with all other snippets that are on a vertex hook. A hook for manipulating the point size of a vertex. This is only used if cogl_pipeline_set_per_vertex_point_size() is enabled on the pipeline. A hook for the entire fragment processing stage of the pipeline. A hook for declaring global data wthat can be shared with all other snippets that are on a fragment hook. A hook for applying the layer matrix to a texture coordinate for a layer. A hook for the fragment processing of a particular layer. A hook for the texture lookup stage of a given layer in a pipeline. Represents how draw should affect the two buffers of a stereo framebuffer. See cogl_framebuffer_set_stereo_mode(). draw to both stereo buffers draw only to the left stereo buffer draw only to the left stereo buffer Error enumeration for Cogl The @COGL_SYSTEM_ERROR_UNSUPPORTED error can be thrown for a variety of reasons. For example: <itemizedlist> <listitem><para>You've tried to use a feature that is not advertised by cogl_has_feature().</para></listitem> <listitem><para>The GPU can not handle the configuration you have requested. An example might be if you try to use too many texture layers in a single #CoglPipeline</para></listitem> <listitem><para>The driver does not support some configuration.</para></listiem> </itemizedlist> Currently this is only used by Cogl API marked as experimental so this enum should also be considered experimental. You tried to use a feature or configuration not currently available. You tried to allocate a resource such as a texture and there wasn't enough memory. Explicitly allocates the storage for the given @texture which allows you to be sure that there is enough memory for the texture and if not then the error can be handled gracefully. <note>Normally applications don't need to use this api directly since the texture will be implicitly allocated when data is set on the texture, or if the texture is attached to a #CoglOffscreen framebuffer and rendered too.</note> %TRUE if the texture was successfully allocated, otherwise %FALSE and @error will be updated if it wasn't %NULL. A #CoglTexture Queries what components the given @texture stores internally as set via cogl_texture_set_components(). For textures created by the ‘_with_size’ constructors the default is %COGL_TEXTURE_COMPONENTS_RGBA. The other constructors which take a %CoglBitmap or a data pointer default to the same components as the pixel format of the data. a #CoglTexture pointer. Copies the pixel data from a cogl texture to system memory. <note>Don't pass the value of cogl_texture_get_rowstride() as the @rowstride argument, the rowstride should be the rowstride you want for the destination @data buffer not the rowstride of the source texture</note> the size of the texture data in bytes a #CoglTexture pointer. the #CoglPixelFormat to store the texture as. the rowstride of @data in bytes or pass 0 to calculate from the bytes-per-pixel of @format multiplied by the @texture width. memory location to write the @texture's contents, or %NULL to only query the data size through the return value. Queries the GL handles for a GPU side texture through its #CoglTexture. If the texture is spliced the data for the first sub texture will be queried. %TRUE if the handle was successfully retrieved, %FALSE if the handle was invalid a #CoglTexture pointer. pointer to return location for the textures GL handle, or %NULL. pointer to return location for the GL target type, or %NULL. Queries the height of a cogl texture. the height of the GPU side texture in pixels a #CoglTexture pointer. Queries the maximum wasted (unused) pixels in one dimension of a GPU side texture. the maximum waste a #CoglTexture pointer. Queries the pre-multiplied alpha status for internally stored red, green and blue components for the given @texture as set by cogl_texture_set_premultiplied(). By default the pre-multipled state is @TRUE. %TRUE if red, green and blue components are internally stored pre-multiplied by the alpha value or %FALSE if not. a #CoglTexture pointer. Queries the width of a cogl texture. the width of the GPU side texture in pixels a #CoglTexture pointer. Queries if a texture is sliced (stored as multiple GPU side tecture objects). %TRUE if the texture is sliced, %FALSE if the texture is stored as a single GPU texture a #CoglTexture pointer. Affects the internal storage format for this texture by specifying what components will be required for sampling later. This api affects how data is uploaded to the GPU since unused components can potentially be discarded from source data. For textures created by the ‘_with_size’ constructors the default is %COGL_TEXTURE_COMPONENTS_RGBA. The other constructors which take a %CoglBitmap or a data pointer default to the same components as the pixel format of the data. Note that the %COGL_TEXTURE_COMPONENTS_RG format is not available on all drivers. The availability can be determined by checking for the %COGL_FEATURE_ID_TEXTURE_RG feature. If this format is used on a driver where it is not available then %COGL_TEXTURE_ERROR_FORMAT will be raised when the texture is allocated. Even if the feature is not available then %COGL_PIXEL_FORMAT_RG_88 can still be used as an image format as long as %COGL_TEXTURE_COMPONENTS_RG isn't used as the texture's components. a #CoglTexture pointer. @texture a #CoglTexture. Sets all the pixels for a given mipmap @level by copying the pixel data pointed to by the @data argument into the given @texture. @data should point to the first pixel to copy corresponding to the top left of the mipmap @level being set. If @rowstride equals 0 then it will be automatically calculated from the width of the mipmap level and the bytes-per-pixel for the given @format. A mipmap @level of 0 corresponds to the largest, base image of a texture and @level 1 is half the width and height of level 0. If dividing any dimension of the previous level by two results in a fraction then round the number down (floor()), but clamp to 1 something like this: |[ next_width = MAX (1, floor (prev_width)); ]| You can determine the number of mipmap levels for a given texture like this: |[ n_levels = 1 + floor (log2 (max_dimension)); ]| Where %max_dimension is the larger of cogl_texture_get_width() and cogl_texture_get_height(). It is an error to pass a @level number >= the number of levels that @texture can have according to the above calculation. <note>Since the storage for a #CoglTexture is allocated lazily then if the given @texture has not previously been allocated then this api can return %FALSE and throw an exceptional @error if there is not enough memory to allocate storage for @texture.</note> %TRUE if the data upload was successful, and %FALSE otherwise the #CoglPixelFormat used in the source @data buffer. rowstride of the source @data buffer (computed from the texture width and @format if it equals 0) the source data, pointing to the first top-left pixel to set The mipmap level to update (Normally 0 for the largest, base texture) Affects the internal storage format for this texture by specifying whether red, green and blue color components should be stored as pre-multiplied alpha values. This api affects how data is uploaded to the GPU since Cogl will convert source data to have premultiplied or unpremultiplied components according to this state. For example if you create a texture via cogl_texture_2d_new_with_size() and then upload data via cogl_texture_set_data() passing a source format of %COGL_PIXEL_FORMAT_RGBA_8888 then Cogl will internally multiply the red, green and blue components of the source data by the alpha component, for each pixel so that the internally stored data has pre-multiplied alpha components. If you instead upload data that already has pre-multiplied components by passing %COGL_PIXEL_FORMAT_RGBA_8888_PRE as the source format to cogl_texture_set_data() then the data can be uploaded without being converted. By default the @premultipled state is @TRUE. a #CoglTexture pointer. Whether any internally stored red, green or blue components are pre-multiplied by an alpha component. Sets the pixels in a rectangular subregion of @texture from an in-memory buffer containing pixel data. <note>The region set can't be larger than the source @data</note> %TRUE if the subregion upload was successful, and %FALSE otherwise a #CoglTexture. upper left coordinate to use from source data. upper left coordinate to use from source data. upper left destination horizontal coordinate. upper left destination vertical coordinate. width of destination region to write. (Must be less than or equal to @width) height of destination region to write. (Must be less than or equal to @height) width of source data buffer. height of source data buffer. the #CoglPixelFormat used in the source buffer. rowstride of source buffer (computed from width if none specified) the actual pixel data. Copies a specified source region from @bitmap to the position (@src_x, @src_y) of the given destination texture @handle. <note>The region updated can't be larger than the source bitmap</note> %TRUE if the subregion upload was successful, and %FALSE otherwise a #CoglTexture pointer upper left coordinate to use from the source bitmap. upper left coordinate to use from the source bitmap upper left destination horizontal coordinate. upper left destination vertical coordinate. width of destination region to write. (Must be less than or equal to the bitmap width) height of destination region to write. (Must be less than or equal to the bitmap height) The source bitmap to read from Creates a low-level #CoglTexture2D texture based on data residing in a #CoglBitmap. The storage for the texture is not allocated before this function returns. You can call cogl_texture_allocate() to explicitly allocate the underlying storage or preferably let Cogl automatically allocate storage lazily when it may know more about how the texture is being used and can optimize how it is allocated. The texture is still configurable until it has been allocated so for example you can influence the internal format of the texture using cogl_texture_set_components() and cogl_texture_set_premultiplied(). A newly allocated #CoglTexture2D A #CoglBitmap Creates a low-level #CoglTexture2D texture based on data residing in memory. <note>This api will always immediately allocate GPU memory for the texture and upload the given data so that the @data pointer does not need to remain valid once this function returns. This means it is not possible to configure the texture before it is allocated. If you do need to configure the texture before allocation (to specify constraints on the internal format for example) then you can instead create a #CoglBitmap for your data and use cogl_texture_2d_new_from_bitmap() or use cogl_texture_2d_new_with_size() and then upload data using cogl_texture_set_data()</note> A newly allocated #CoglTexture2D, or if the size is not supported (because it is too large or a non-power-of-two size that the hardware doesn't support) it will return %NULL and set @error. A #CoglContext width of texture in pixels height of texture in pixels the #CoglPixelFormat the buffer is stored in in RAM the memory offset in bytes between the starts of scanlines in @data. A value of 0 will make Cogl automatically calculate @rowstride from @width and @format. pointer the memory region where the source buffer resides Creates a low-level #CoglTexture2D texture from an image file. The storage for the texture is not allocated before this function returns. You can call cogl_texture_allocate() to explicitly allocate the underlying storage or preferably let Cogl automatically allocate storage lazily when it may know more about how the texture is being used and can optimize how it is allocated. The texture is still configurable until it has been allocated so for example you can influence the internal format of the texture using cogl_texture_set_components() and cogl_texture_set_premultiplied(). A newly created #CoglTexture2D or %NULL on failure and @error will be updated. A #CoglContext the file to load Creates a low-level #CoglTexture2D texture with a given @width and @height that your GPU can texture from directly. The storage for the texture is not allocated before this function returns. You can call cogl_texture_allocate() to explicitly allocate the underlying storage or preferably let Cogl automatically allocate storage lazily when it may know more about how the texture is being used and can optimize how it is allocated. The texture is still configurable until it has been allocated so for example you can influence the internal format of the texture using cogl_texture_set_components() and cogl_texture_set_premultiplied(). A new #CoglTexture2D object with no storage yet allocated. A #CoglContext Width of the texture to allocate Height of the texture to allocate format of the texture to allocate Creates a low-level #CoglTexture2D texture with a given @width and @height that your GPU can texture from directly. The storage for the texture is not allocated before this function returns. You can call cogl_texture_allocate() to explicitly allocate the underlying storage or preferably let Cogl automatically allocate storage lazily when it may know more about how the texture is being used and can optimize how it is allocated. The texture is still configurable until it has been allocated so for example you can influence the internal format of the texture using cogl_texture_set_components() and cogl_texture_set_premultiplied(). A new #CoglTexture2D object with no storage yet allocated. A #CoglContext Width of the texture to allocate Height of the texture to allocate Creates a new #CoglTexture2DSliced texture based on data residing in a bitmap. A #CoglTexture2DSliced may internally be comprised of 1 or more #CoglTexture2D textures depending on GPU limitations. For example if the GPU only supports power-of-two sized textures then a sliced texture will turn a non-power-of-two size into a combination of smaller power-of-two sized textures. If the requested texture size is larger than is supported by the hardware then the texture will be sliced into smaller textures that can be accessed by the hardware. @max_waste is used as a threshold for recursively slicing the right-most or bottom-most slices into smaller sizes until the wasted padding at the bottom and right of the textures is less than specified. A negative @max_waste will disable slicing. The storage for the texture is not allocated before this function returns. You can call cogl_texture_allocate() to explicitly allocate the underlying storage or let Cogl automatically allocate storage lazily. <note>It's possible for the allocation of a sliced texture to fail later due to impossible slicing constraints if a negative @max_waste value is given. If the given virtual texture size is larger than is supported by the hardware but slicing is disabled the texture size would be too large to handle.</note> A newly created #CoglTexture2DSliced or %NULL on failure and @error will be updated. A #CoglBitmap The threshold of how wide a strip of wasted texels are allowed along the right and bottom textures before they must be sliced to reduce the amount of waste. A negative can be passed to disable slicing. Creates a new #CoglTexture2DSliced texture based on data residing in memory. A #CoglTexture2DSliced may internally be comprised of 1 or more #CoglTexture2D textures depending on GPU limitations. For example if the GPU only supports power-of-two sized textures then a sliced texture will turn a non-power-of-two size into a combination of smaller power-of-two sized textures. If the requested texture size is larger than is supported by the hardware then the texture will be sliced into smaller textures that can be accessed by the hardware. @max_waste is used as a threshold for recursively slicing the right-most or bottom-most slices into smaller sizes until the wasted padding at the bottom and right of the textures is less than specified. A negative @max_waste will disable slicing. <note>This api will always immediately allocate GPU memory for all the required texture slices and upload the given data so that the @data pointer does not need to remain valid once this function returns. This means it is not possible to configure the texture before it is allocated. If you do need to configure the texture before allocation (to specify constraints on the internal format for example) then you can instead create a #CoglBitmap for your data and use cogl_texture_2d_sliced_new_from_bitmap() or use cogl_texture_2d_sliced_new_with_size() and then upload data using cogl_texture_set_data()</note> <note>It's possible for the allocation of a sliced texture to fail due to impossible slicing constraints if a negative @max_waste value is given. If the given virtual texture size is larger than is supported by the hardware but slicing is disabled the texture size would be too large to handle.</note> A newly created #CoglTexture2DSliced or %NULL on failure and @error will be updated. A #CoglContext width of texture in pixels height of texture in pixels The threshold of how wide a strip of wasted texels are allowed along the right and bottom textures before they must be sliced to reduce the amount of waste. A negative can be passed to disable slicing. the #CoglPixelFormat the buffer is stored in in RAM the memory offset in bytes between the start of each row in @data. A value of 0 will make Cogl automatically calculate @rowstride from @width and @format. pointer the memory region where the source buffer resides Creates a #CoglTexture2DSliced from an image file. A #CoglTexture2DSliced may internally be comprised of 1 or more #CoglTexture2D textures depending on GPU limitations. For example if the GPU only supports power-of-two sized textures then a sliced texture will turn a non-power-of-two size into a combination of smaller power-of-two sized textures. If the requested texture size is larger than is supported by the hardware then the texture will be sliced into smaller textures that can be accessed by the hardware. @max_waste is used as a threshold for recursively slicing the right-most or bottom-most slices into smaller sizes until the wasted padding at the bottom and right of the textures is less than specified. A negative @max_waste will disable slicing. The storage for the texture is not allocated before this function returns. You can call cogl_texture_allocate() to explicitly allocate the underlying storage or let Cogl automatically allocate storage lazily. <note>It's possible for the allocation of a sliced texture to fail later due to impossible slicing constraints if a negative @max_waste value is given. If the given virtual texture size is larger than is supported by the hardware but slicing is disabled the texture size would be too large to handle.</note> A newly created #CoglTexture2DSliced or %NULL on failure and @error will be updated. A #CoglContext the file to load The threshold of how wide a strip of wasted texels are allowed along the right and bottom textures before they must be sliced to reduce the amount of waste. A negative can be passed to disable slicing. Creates a #CoglTexture2DSliced that may internally be comprised of 1 or more #CoglTexture2D textures depending on GPU limitations. For example if the GPU only supports power-of-two sized textures then a sliced texture will turn a non-power-of-two size into a combination of smaller power-of-two sized textures. If the requested texture size is larger than is supported by the hardware then the texture will be sliced into smaller textures that can be accessed by the hardware. @max_waste is used as a threshold for recursively slicing the right-most or bottom-most slices into smaller sizes until the wasted padding at the bottom and right of the textures is less than specified. A negative @max_waste will disable slicing. The storage for the texture is not allocated before this function returns. You can call cogl_texture_allocate() to explicitly allocate the underlying storage or let Cogl automatically allocate storage lazily. <note>It's possible for the allocation of a sliced texture to fail later due to impossible slicing constraints if a negative @max_waste value is given. If the given virtual texture size size is larger than is supported by the hardware but slicing is disabled the texture size would be too large to handle.</note> A new #CoglTexture2DSliced object with no storage allocated yet. A #CoglContext The virtual width of your sliced texture. The virtual height of your sliced texture. The threshold of how wide a strip of wasted texels are allowed along the right and bottom textures before they must be sliced to reduce the amount of waste. A negative can be passed to disable slicing. See cogl_texture_set_components(). Only the alpha component Red and green components. Note that this can only be used if the %COGL_FEATURE_ID_TEXTURE_RG feature is advertised. Red, green and blue components Red, green, blue and alpha components Only a depth component Error codes that can be thrown when allocating textures. Unsupported size Unsupported format A primitive texture type that is unsupported by the driver was used Used to specify vertex information when calling cogl_polygon() Model x-coordinate Model y-coordinate Model z-coordinate Texture x-coordinate Texture y-coordinate The color to use at this vertex. This is ignored if use_color is %FALSE when calling cogl_polygon() A #CoglUserDataKey is used to declare a key for attaching data to a #CoglObject using cogl_object_set_user_data. The typedef only exists as a formality to make code self documenting since only the unique address of a #CoglUserDataKey is used. Typically you would declare a static #CoglUserDataKey and set private data on an object something like this: |[ static CoglUserDataKey path_private_key; static void destroy_path_private_cb (void *data) { g_free (data); } static void my_path_set_data (CoglPipeline *pipeline, void *data) { cogl_object_set_user_data (COGL_OBJECT (pipeline), &private_key, data, destroy_pipeline_private_cb); } ]| ignored. Different ways of interpreting vertices when drawing. FIXME, equivalent to <constant>GL_POINTS</constant> FIXME, equivalent to <constant>GL_LINES</constant> FIXME, equivalent to <constant>GL_LINE_LOOP</constant> FIXME, equivalent to <constant>GL_LINE_STRIP</constant> FIXME, equivalent to <constant>GL_TRIANGLES</constant> FIXME, equivalent to <constant>GL_TRIANGLE_STRIP</constant> FIXME, equivalent to <constant>GL_TRIANGLE_FAN</constant> Enum used to represent the two directions of rotation. This can be used to set the front face for culling by calling cogl_pipeline_set_front_face_winding(). Vertices are in a clockwise order Vertices are in a counter-clockwise order @return FALSE for an immediately detected error, TRUE otherwise. This blits a region of the color buffer of the source buffer to the destination buffer. This function should only be called if the COGL_FEATURE_ID_BLIT_FRAMEBUFFER feature is advertised. The source and destination rectangles are defined in offscreen framebuffer orientation. When copying between an offscreen and onscreen framebuffers, the image is y-flipped accordingly. The two buffers must have the same value types (e.g. floating-point, unsigned int, signed int, or fixed-point), but color formats do not need to match. This limitation comes from OpenGL ES 3.0 definition of glBlitFramebuffer. Note that this function differs a lot from the glBlitFramebuffer function provided by the GL_EXT_framebuffer_blit extension. Notably it doesn't support having different sizes for the source and destination rectangle. This doesn't seem like a particularly useful feature. If the application wanted to scale the results it may make more sense to draw a primitive instead. The GL function is documented to be affected by the scissor. This function therefore ensure that an empty clip stack is flushed before performing the blit which means the scissor is effectively ignored. The function also doesn't support specifying the buffers to copy and instead only the color buffer is copied. When copying the depth or stencil buffers the extension on GLES2.0 only supports copying the full buffer which would be awkward to document with this API. If we wanted to support that feature it may be better to have a separate function to copy the entire buffer for a given mask. The @c error argument is optional, it can be NULL. If it is not NULL and this function returns FALSE, an error object with a code from COGL_SYSTEM_ERROR will be created. The source #CoglFramebuffer The destination #CoglFramebuffer Source x position Source y position Destination x position Destination y position Width of region to copy Height of region to copy Clears a reference to a #CoglObject. @object_ptr must not be %NULL. If the reference is %NULL then this function does nothing. Otherwise, the reference count of the object is decreased using cogl_object_unref() and the pointer is set to %NULL. a pointer to a #CoglObject reference General utility functions for COGL. Cogl allows loading image data into memory as CoglBitmaps without loading them immediately into GPU textures. #CoglBitmap is available since Cogl 1.0 #CoglColor is a simple structure holding the definition of a color such that it can be efficiently used by GL A #CoglContext is the top most sandbox of Cogl state for an application or toolkit. Its main purpose is to act as a sandbox for the memory management of state objects. Normally an application will only create a single context since there is no way to share resources between contexts. For those familiar with OpenGL or perhaps Cairo it should be understood that unlike these APIs a Cogl context isn't a rendering context as such. In other words Cogl doesn't aim to provide a state machine style model for configuring rendering parameters. Most rendering state in Cogl is directly associated with user managed objects called pipelines and geometry is drawn with a specific pipeline object to a framebuffer object and those 3 things fully define the state for drawing. This is an important part of Cogl's design since it helps you write orthogonal rendering components that can all access the same GPU without having to worry about what state other components have left you with. <note><para>Cogl does not maintain internal references to the context for resources that depend on the context so applications. This is to help applications control the lifetime a context without us needing to introduce special api to handle the breakup of internal circular references due to internal resources and caches associated with the context. One a context has been destroyed then all directly or indirectly dependent resources will be in an inconsistent state and should not be manipulated or queried in any way. For applications that rely on the operating system to clean up resources this policy shouldn't affect them, but for applications that need to carefully destroy and re-create Cogl contexts multiple times throughout their lifetime (such as Android applications) they should be careful to destroy all context dependent resources, such as framebuffers or textures etc before unrefing and destroying the context.</para></note> Framebuffers are a collection of buffers that can be rendered too. A framebuffer may be comprised of one or more color buffers, an optional depth buffer and an optional stencil buffer. Other configuration parameters are associated with framebuffers too such as whether the framebuffer supports multi-sampling (an anti-aliasing technique) or dithering. There are two kinds of framebuffer in Cogl, #CoglOnscreen framebuffers and #CoglOffscreen framebuffers. As the names imply offscreen framebuffers are for rendering something offscreen (perhaps to a texture which is bound as one of the color buffers). The exact semantics of onscreen framebuffers depends on the window system backend that you are using, but typically you can expect rendering to a #CoglOnscreen framebuffer will be immediately visible to the user. If you want to create a new framebuffer then you should start by looking at the #CoglOnscreen and #CoglOffscreen constructor functions, such as cogl_offscreen_new_with_texture() or cogl_onscreen_new(). The #CoglFramebuffer interface deals with all aspects that are common between those two types of framebuffer. Setup of a new CoglFramebuffer happens in two stages. There is a configuration stage where you specify all the options and ancillary buffers you want associated with your framebuffer and then when you are happy with the configuration you can "allocate" the framebuffer using cogl_framebuffer_allocate(). Technically explicitly calling cogl_framebuffer_allocate() is optional for convenience and the framebuffer will automatically be allocated when you first try to draw to it, but if you do the allocation manually then you can also catch any possible errors that may arise from your configuration. Cogl allows creating and operating on offscreen framebuffers. Cogl allows creating and manipulating objects representing the full configuration of the GPU pipeline. In simplified terms the GPU pipeline takes primitive geometry as the input, it first performs vertex processing, allowing you to deform your geometry, then rasterizes that (turning it from pure geometry into fragments) then performs fragment processing including depth testing and texture mapping. Finally it blends the result with the framebuffer. The pixel format of an image descrbes how the bits of each pixel are represented in memory. For example: an image can be laid out as one long sequence of pixels, where each pixel is a sequence of 8 bits of Red, Green and Blue. The amount of bits that are used can be different for each pixel format, as well as the components (for example an Alpha layer to include transparency, or non_RGBA). Other examples of factors that can influence the layout in memory are the system's endianness. Cogl allows accessing the GL programmable pipeline in order to create vertex and fragment shaders. When using GLSL Cogl provides replacement names for most of the builtin varyings and uniforms. It is recommended to use these names wherever possible to increase portability between OpenGL 2.0 and GLES 2.0. GLES 2.0 does not have most of the builtins under their original names so they will only work with the Cogl names. For use in all GLSL shaders, the Cogl builtins are as follows: <tip> <glosslist> <glossentry> <glossterm>uniform mat4 <emphasis>cogl_modelview_matrix</emphasis></glossterm> <glossdef><para> The current modelview matrix. This is equivalent to #gl_ModelViewMatrix. </para></glossdef> </glossentry> <glossentry> <glossterm>uniform mat4 <emphasis>cogl_projection_matrix</emphasis></glossterm> <glossdef><para> The current projection matrix. This is equivalent to #gl_ProjectionMatrix. </para></glossdef> </glossentry> <glossentry> <glossterm>uniform mat4 <emphasis>cogl_modelview_projection_matrix</emphasis></glossterm> <glossdef><para> The combined modelview and projection matrix. A vertex shader would typically use this to transform the incoming vertex position. The separate modelview and projection matrices are usually only needed for lighting calculations. This is equivalent to #gl_ModelViewProjectionMatrix. </para></glossdef> </glossentry> <glossentry> <glossterm>uniform mat4 <emphasis>cogl_texture_matrix</emphasis>[]</glossterm> <glossdef><para> An array of matrices for transforming the texture coordinates. This is equivalent to #gl_TextureMatrix. </para></glossdef> </glossentry> </glosslist> </tip> In a vertex shader, the following are also available: <tip> <glosslist> <glossentry> <glossterm>attribute vec4 <emphasis>cogl_position_in</emphasis></glossterm> <glossdef><para> The incoming vertex position. This is equivalent to #gl_Vertex. </para></glossdef> </glossentry> <glossentry> <glossterm>attribute vec4 <emphasis>cogl_color_in</emphasis></glossterm> <glossdef><para> The incoming vertex color. This is equivalent to #gl_Color. </para></glossdef> </glossentry> <glossentry> <glossterm>attribute vec4 <emphasis>cogl_tex_coord_in</emphasis></glossterm> <glossdef><para> The texture coordinate for the first texture unit. This is equivalent to #gl_MultiTexCoord0. </para></glossdef> </glossentry> <glossentry> <glossterm>attribute vec4 <emphasis>cogl_tex_coord0_in</emphasis></glossterm> <glossdef><para> The texture coordinate for the first texture unit. This is equivalent to #gl_MultiTexCoord0. There is also #cogl_tex_coord1_in and so on. </para></glossdef> </glossentry> <glossentry> <glossterm>attribute vec3 <emphasis>cogl_normal_in</emphasis></glossterm> <glossdef><para> The normal of the vertex. This is equivalent to #gl_Normal. </para></glossdef> </glossentry> <glossentry> <glossterm>vec4 <emphasis>cogl_position_out</emphasis></glossterm> <glossdef><para> The calculated position of the vertex. This must be written to in all vertex shaders. This is equivalent to #gl_Position. </para></glossdef> </glossentry> <glossentry> <glossterm>float <emphasis>cogl_point_size_out</emphasis></glossterm> <glossdef><para> The calculated size of a point. This is equivalent to #gl_PointSize. </para></glossdef> </glossentry> <glossentry> <glossterm>varying vec4 <emphasis>cogl_color_out</emphasis></glossterm> <glossdef><para> The calculated color of a vertex. This is equivalent to #gl_FrontColor. </para></glossdef> </glossentry> <glossentry> <glossterm>varying vec4 <emphasis>cogl_tex_coord_out</emphasis>[]</glossterm> <glossdef><para> An array of calculated texture coordinates for a vertex. This is equivalent to #gl_TexCoord. </para></glossdef> </glossentry> </glosslist> </tip> In a fragment shader, the following are also available: <tip> <glosslist> <glossentry> <glossterm>varying vec4 <emphasis>cogl_color_in</emphasis></glossterm> <glossdef><para> The calculated color of a vertex. This is equivalent to #gl_FrontColor. </para></glossdef> </glossentry> <glossentry> <glossterm>varying vec4 <emphasis>cogl_tex_coord_in</emphasis>[]</glossterm> <glossdef><para> An array of calculated texture coordinates for a vertex. This is equivalent to #gl_TexCoord. </para></glossdef> </glossentry> <glossentry> <glossterm>vec4 <emphasis>cogl_color_out</emphasis></glossterm> <glossdef><para> The final calculated color of the fragment. All fragment shaders must write to this variable. This is equivalent to #gl_FrontColor. </para></glossdef> </glossentry> <glossentry> <glossterm>float <emphasis>cogl_depth_out</emphasis></glossterm> <glossdef><para> An optional output variable specifying the depth value to use for this fragment. This is equivalent to #gl_FragDepth. </para></glossdef> </glossentry> <glossentry> <glossterm>bool <emphasis>cogl_front_facing</emphasis></glossterm> <glossdef><para> A readonly variable that will be true if the current primitive is front facing. This can be used to implement two-sided coloring algorithms. This is equivalent to #gl_FrontFacing. </para></glossdef> </glossentry> </glosslist> </tip> It's worth nothing that this API isn't what Cogl would like to have in the long term and it may be removed in Cogl 2.0. The experimental #CoglShader API is the proposed replacement. #CoglSnippet<!-- -->s are used to modify or replace parts of a #CoglPipeline using GLSL. GLSL is a programming language supported by OpenGL on programmable hardware to provide a more flexible description of what should be rendered. A description of GLSL itself is outside the scope of this documentation but any good OpenGL book should help to describe it. Unlike in OpenGL, when using GLSL with Cogl it is possible to write short snippets to replace small sections of the pipeline instead of having to replace the whole of either the vertex or fragment pipelines. Of course it is also possible to replace the whole of the pipeline if needed. Each snippet is a standalone chunk of code which would attach to the pipeline at a particular point. The code is split into four separate strings (all of which are optional): <glosslist> <glossentry> <glossterm>declarations</glossterm> <glossdef><para> The code in this string will be inserted outside of any function in the global scope of the shader. This can be used to declare uniforms, attributes, varyings and functions to be used by the snippet. </para></glossdef> </glossentry> <glossentry> <glossterm>pre</glossterm> <glossdef><para> The code in this string will be inserted before the hook point. </para></glossdef> </glossentry> <glossentry> <glossterm>post</glossterm> <glossdef><para> The code in this string will be inserted after the hook point. This can be used to modify the results of the builtin generated code for that hook point. </para></glossdef> </glossentry> <glossentry> <glossterm>replace</glossterm> <glossdef><para> If present the code in this string will replace the generated code for the hook point. </para></glossdef> </glossentry> </glosslist> All of the strings apart from the declarations string of a pipeline are generated in a single function so they can share variables declared from one string in another. The scope of the code is limited to each snippet so local variables declared in the snippet will not collide with variables declared in another snippet. However, code in the 'declarations' string is global to the shader so it is the application's responsibility to ensure that variables declared here will not collide with those from other snippets. The snippets can be added to a pipeline with cogl_pipeline_add_snippet() or cogl_pipeline_add_layer_snippet(). Which function to use depends on which hook the snippet is targeting. The snippets are all generated in the order they are added to the pipeline. That is, the post strings are executed in the order they are added to the pipeline and the pre strings are executed in reverse order. If any replace strings are given for a snippet then any other snippets with the same hook added before that snippet will be ignored. The different hooks are documented under #CoglSnippetHook. For portability with GLES2, it is recommended not to use the GLSL builtin names such as gl_FragColor. Instead there are replacement names under the cogl_* namespace which can be used instead. These are: <glosslist> <glossentry> <glossterm>uniform mat4 <emphasis>cogl_modelview_matrix</emphasis></glossterm> <glossdef><para> The current modelview matrix. This is equivalent to #gl_ModelViewMatrix. </para></glossdef> </glossentry> <glossentry> <glossterm>uniform mat4 <emphasis>cogl_projection_matrix</emphasis></glossterm> <glossdef><para> The current projection matrix. This is equivalent to #gl_ProjectionMatrix. </para></glossdef> </glossentry> <glossentry> <glossterm>uniform mat4 <emphasis>cogl_modelview_projection_matrix</emphasis></glossterm> <glossdef><para> The combined modelview and projection matrix. A vertex shader would typically use this to transform the incoming vertex position. The separate modelview and projection matrices are usually only needed for lighting calculations. This is equivalent to #gl_ModelViewProjectionMatrix. </para></glossdef> </glossentry> <glossentry> <glossterm>uniform mat4 <emphasis>cogl_texture_matrix</emphasis>[]</glossterm> <glossdef><para> An array of matrices for transforming the texture coordinates. This is equivalent to #gl_TextureMatrix. </para></glossdef> </glossentry> </glosslist> In a vertex shader, the following are also available: <glosslist> <glossentry> <glossterm>attribute vec4 <emphasis>cogl_position_in</emphasis></glossterm> <glossdef><para> The incoming vertex position. This is equivalent to #gl_Vertex. </para></glossdef> </glossentry> <glossentry> <glossterm>attribute vec4 <emphasis>cogl_color_in</emphasis></glossterm> <glossdef><para> The incoming vertex color. This is equivalent to #gl_Color. </para></glossdef> </glossentry> <glossentry> <glossterm>attribute vec4 <emphasis>cogl_tex_coord_in</emphasis></glossterm> <glossdef><para> The texture coordinate for layer 0. This is an alternative name for #cogl_tex_coord0_in. </para></glossdef> </glossentry> <glossentry> <glossterm>attribute vec4 <emphasis>cogl_tex_coord0_in</emphasis></glossterm> <glossdef><para> The texture coordinate for the layer 0. This is equivalent to #gl_MultiTexCoord0. There will also be #cogl_tex_coord1_in and so on if more layers are added to the pipeline. </para></glossdef> </glossentry> <glossentry> <glossterm>attribute vec3 <emphasis>cogl_normal_in</emphasis></glossterm> <glossdef><para> The normal of the vertex. This is equivalent to #gl_Normal. </para></glossdef> </glossentry> <glossentry> <glossterm>vec4 <emphasis>cogl_position_out</emphasis></glossterm> <glossdef><para> The calculated position of the vertex. This must be written to in all vertex shaders. This is equivalent to #gl_Position. </para></glossdef> </glossentry> <glossentry> <glossterm>float <emphasis>cogl_point_size_in</emphasis></glossterm> <glossdef><para> The incoming point size from the cogl_point_size_in attribute. This is only available if cogl_pipeline_set_per_vertex_point_size() is set on the pipeline. </para></glossdef> </glossentry> <glossentry> <glossterm>float <emphasis>cogl_point_size_out</emphasis></glossterm> <glossdef><para> The calculated size of a point. This is equivalent to #gl_PointSize. </para></glossdef> </glossentry> <glossentry> <glossterm>varying vec4 <emphasis>cogl_color_out</emphasis></glossterm> <glossdef><para> The calculated color of a vertex. This is equivalent to #gl_FrontColor. </para></glossdef> </glossentry> <glossentry> <glossterm>varying vec4 <emphasis>cogl_tex_coord0_out</emphasis></glossterm> <glossdef><para> The calculated texture coordinate for layer 0 of the pipeline. This is equivalent to #gl_TexCoord[0]. There will also be #cogl_tex_coord1_out and so on if more layers are added to the pipeline. In the fragment shader, this varying is called #cogl_tex_coord0_in. </para></glossdef> </glossentry> </glosslist> In a fragment shader, the following are also available: <glosslist> <glossentry> <glossterm>varying vec4 <emphasis>cogl_color_in</emphasis></glossterm> <glossdef><para> The calculated color of a vertex. This is equivalent to #gl_FrontColor. </para></glossdef> </glossentry> <glossentry> <glossterm>varying vec4 <emphasis>cogl_tex_coord0_in</emphasis></glossterm> <glossdef><para> The texture coordinate for layer 0. This is equivalent to #gl_TexCoord[0]. There will also be #cogl_tex_coord1_in and so on if more layers are added to the pipeline. </para></glossdef> </glossentry> <glossentry> <glossterm>vec4 <emphasis>cogl_color_out</emphasis></glossterm> <glossdef><para> The final calculated color of the fragment. All fragment shaders must write to this variable. This is equivalent to #gl_FrontColor. </para></glossdef> </glossentry> <glossentry> <glossterm>float <emphasis>cogl_depth_out</emphasis></glossterm> <glossdef><para> An optional output variable specifying the depth value to use for this fragment. This is equivalent to #gl_FragDepth. </para></glossdef> </glossentry> <glossentry> <glossterm>bool <emphasis>cogl_front_facing</emphasis></glossterm> <glossdef><para> A readonly variable that will be true if the current primitive is front facing. This can be used to implement two-sided coloring algorithms. This is equivalent to #gl_FrontFacing. </para></glossdef> </glossentry> <glossentry> <glossterm>vec2 <emphasis>cogl_point_coord</emphasis></glossterm> <glossdef><para> When rendering points, this will contain a vec2 which represents the position within the point of the current fragment. vec2(0.0,0.0) will be the topleft of the point and vec2(1.0,1.0) will be the bottom right. Note that there is currently a bug in Cogl where when rendering to an offscreen buffer these coordinates will be upside-down. The value is undefined when not rendering points. </para></glossdef> </glossentry> </glosslist> Here is an example of using a snippet to add a desaturate effect to the generated color on a pipeline. <programlisting> CoglPipeline *pipeline = cogl_pipeline_new (); /<!-- -->* Set up the pipeline here, ie by adding a texture or other layers *<!-- -->/ /<!-- -->* Create the snippet. The first string is the declarations which we will use to add a uniform. The second is the 'post' string which will contain the code to perform the desaturation. *<!-- -->/ CoglSnippet *snippet = cogl_snippet_new (COGL_SNIPPET_HOOK_FRAGMENT, "uniform float factor;", "float gray = dot (vec3 (0.299, 0.587, 0.114), " " cogl_color_out.rgb);" "cogl_color_out.rgb = mix (vec3 (gray)," " cogl_color_out.rgb," " factor);"); /<!-- -->* Add it to the pipeline *<!-- -->/ cogl_pipeline_add_snippet (pipeline, snippet); /<!-- -->* The pipeline keeps a reference to the snippet so we don't need to *<!-- -->/ cogl_object_unref (snippet); /<!-- -->* Update the custom uniform on the pipeline *<!-- -->/ int location = cogl_pipeline_get_uniform_location (pipeline, "factor"); cogl_pipeline_set_uniform_1f (pipeline, location, 0.5f); /<!-- -->* Now we can render with the snippet as usual *<!-- -->/ cogl_push_source (pipeline); cogl_rectangle (0, 0, 10, 10); cogl_pop_source (); </programlisting> Cogl allows creating and manipulating textures using a uniform API that tries to hide all the various complexities of creating, loading and manipulating textures. These functions allow low-level 2D textures to be allocated. These differ from sliced textures for example which may internally be made up of multiple 2D textures, or atlas textures where Cogl must internally modify user texture coordinates before they can be used by the GPU. These functions allow high-level meta textures (See the #CoglMetaTexture interface) to be allocated that may internally be comprised of multiple 2D texture "slices" with power-of-two sizes. This API can be useful when working with GPUs that don't have native support for non-power-of-two textures or if you want to load a texture that is larger than the GPUs maximum texture size limits. The algorithm for slicing works by first trying to map a virtual size to the next larger power-of-two size and then seeing how many wasted pixels that would result in. For example if you have a virtual texture that's 259 texels wide, the next pot size = 512 and the amount of waste would be 253 texels. If the amount of waste is above a max-waste threshold then we would next slice that texture into one that's 256 texels and then looking at how many more texels remain unallocated after that we choose the next power-of-two size. For the example of a 259 texel image that would mean having a 256 texel wide texture, leaving 3 texels unallocated so we'd then create a 4 texel wide texture - now there is only one texel of waste. The algorithm continues to slice the right most textures until the amount of waste is less than or equal to a specified max-waste threshold. The same logic for slicing from left to right is also applied from top to bottom. General types used by various Cogl functions. Compares two #CoglColor<!-- -->s and checks if they are the same. This function can be passed to g_hash_table_new() as the @key_equal_func parameter, when using #CoglColor<!-- -->s as keys in a #GHashTable. %TRUE if the two colors are the same. a #CoglColor a #CoglColor Converts a color expressed in HLS (hue, luminance and saturation) values into a #CoglColor. return location for a #CoglColor hue value, in the 0 .. 360 range saturation value, in the 0 .. 1 range luminance value, in the 0 .. 1 range Create a new cogl program object that can be used to replace parts of the GL rendering pipeline with custom code. Use #CoglSnippet api a new cogl program. Create a new shader handle, use cogl_shader_source() to set the source code to be used on it. Use #CoglSnippet api a new shader handle. COGL_SHADER_TYPE_VERTEX or COGL_SHADER_TYPE_FRAGMENT. Invokes @func once for each type of object that Cogl uses and passes a count of the number of objects for that type. This is intended to be used solely for debugging purposes to track down issues with objects leaking. A callback function for each type A pointer to pass to @func Prints a list of all the object types that Cogl uses along with the number of objects of that type that are currently in use. This is intended to be used solely for debugging purposes to track down issues with objects leaking. This function should only need to be called in exceptional circumstances. As an optimization Cogl drawing functions may batch up primitives internally, so if you are trying to use raw GL outside of Cogl you stand a better chance of being successful if you ask Cogl to flush any batched geometry before making your state changes. It only ensure that the underlying driver is issued all the commands necessary to draw the batched primitives. It provides no guarantees about when the driver will complete the rendering. This provides no guarantees about the GL state upon returning and to avoid confusing Cogl you should aim to restore any changes you make before resuming use of Cogl. If you are making state changes with the intention of affecting Cogl drawing primitives you are 100% on your own since you stand a good chance of conflicting with Cogl internals. For example clutter-gst which currently uses direct GL calls to bind ARBfp programs will very likely break when Cogl starts to use ARBfb programs itself for the material API. Iterates through all the context level features currently supported for a given @context and for each feature @callback is called. A #CoglContext pointer A #CoglFeatureCallback called for each supported feature Private data to pass to the callback Returns the graphics reset status as reported by GetGraphicsResetStatusARB defined in the ARB_robustness extension. Note that Cogl doesn't normally enable the ARB_robustness extension in which case this will only ever return #COGL_GRAPHICS_RESET_STATUS_NO_ERROR. Applications must explicitly use a backend specific method to request that errors get reported such as X11's cogl_xlib_renderer_request_reset_on_video_memory_purge(). a #CoglGraphicsResetStatus a #CoglContext pointer Gets a pointer to a given GL or GL ES extension function. This acts as a wrapper around glXGetProcAddress() or whatever is the appropriate function for the current backend. <note>This function should not be used to query core opengl API symbols since eglGetProcAddress for example doesn't allow this and and may return a junk pointer if you do.</note> a pointer to the requested function or %NULL if the function is not available. the name of the function. Checks if a given @feature is currently available Cogl does not aim to be a lowest common denominator API, it aims to expose all the interesting features of GPUs to application which means applications have some responsibility to explicitly check that certain features are available before depending on them. %TRUE if the @feature is currently supported or %FALSE if not. A #CoglContext pointer A #CoglFeatureID Checks if a list of features are all currently available. This checks all of the listed features using cogl_has_feature() and returns %TRUE if all the features are available or %FALSE otherwise. %TRUE if all the features are available, %FALSE otherwise. A #CoglContext pointer A 0 terminated list of CoglFeatureID<!-- -->s Checks whether @object is a #CoglBitmap %TRUE if the passed @object represents a bitmap, and %FALSE otherwise a #CoglObject pointer Gets whether the given object references an existing context object. %TRUE if the @object references a #CoglContext, %FALSE otherwise An object or %NULL Gets whether the given object references a #CoglFrameInfo. %TRUE if the object references a #CoglFrameInfo and %FALSE otherwise. A #CoglObject pointer Gets whether the given object references a #CoglFramebuffer. %TRUE if the object references a #CoglFramebuffer and %FALSE otherwise. A #CoglObject pointer Gets whether the given @object references an existing pipeline object. %TRUE if the @object references a #CoglPipeline, %FALSE otherwise A #CoglObject Gets whether the given handle references an existing program object. Use #CoglSnippet api %TRUE if the handle references a program, %FALSE otherwise A CoglHandle Gets whether the given handle references an existing shader object. Use #CoglSnippet api %TRUE if the handle references a shader, %FALSE otherwise A CoglHandle Gets whether the given @object references an existing snippet object. %TRUE if the @object references a #CoglSnippet, %FALSE otherwise A #CoglObject pointer Gets whether the given object references a texture object. %TRUE if the @object references a texture, and %FALSE otherwise A #CoglObject pointer Gets whether the given object references an existing #CoglTexture2D object. %TRUE if the object references a #CoglTexture2D, %FALSE otherwise A #CoglObject Gets whether the given object references a #CoglTexture2DSliced. %TRUE if the object references a #CoglTexture2DSliced and %FALSE otherwise. A #CoglObject pointer Queries the number of bytes per pixel for a given format in the given plane. The number of bytes per pixel in the given format's given plane. The pixel format The index of the plane (should not be more than the number of planes in the given format). Returns the number of planes the given CoglPixelFormat specifies. The no. of planes of @format (at most %COGL_PIXEL_FORMAT_MAX_PLANES) The format for which to get the number of planes Returns a string representation of @format, useful for debugging purposes. A string representation of @format. a #CoglPixelFormat Attaches a shader to a program object. A program can have multiple vertex or fragment shaders but only one of them may provide a main() function. It is allowed to use a program with only a vertex shader or only a fragment shader. Use #CoglSnippet api a #CoglHandle for a shdaer program. a #CoglHandle for a vertex of fragment shader. Retrieve the location (offset) of a uniform variable in a shader program, a uniform is a variable that is constant for all vertices/fragments for a shader object and is possible to modify as an external parameter. Use #CoglSnippet api instead the offset of a uniform in a specified program. a #CoglHandle for a shader program. the name of a uniform. Links a program making it ready for use. Note that calling this function is optional. If it is not called the program will automatically be linked the first time it is used. Use #CoglSnippet api a #CoglHandle for a shader program. Changes the value of a floating point uniform for the given linked @program. Use #CoglSnippet api instead A #CoglHandle for a linked program the uniform location retrieved from cogl_program_get_uniform_location(). the new value of the uniform. Changes the value of an integer uniform for the given linked @program. Use #CoglSnippet api instead A #CoglHandle for a linked program the uniform location retrieved from cogl_program_get_uniform_location(). the new value of the uniform. Changes the value of a float vector uniform, or uniform array for the given linked @program. Use #CoglSnippet api instead A #CoglHandle for a linked program the uniform location retrieved from cogl_program_get_uniform_location(). The number of components for the uniform. For example with glsl you'd use 3 for a vec3 or 4 for a vec4. For uniform arrays this is the array length otherwise just pass 1 the new value of the uniform[s]. Changes the value of a int vector uniform, or uniform array for the given linked @program. Use #CoglSnippet api instead A #CoglHandle for a linked program the uniform location retrieved from cogl_program_get_uniform_location(). The number of components for the uniform. For example with glsl you'd use 3 for a vec3 or 4 for a vec4. For uniform arrays this is the array length otherwise just pass 1 the new value of the uniform[s]. Changes the value of a matrix uniform, or uniform array in the given linked @program. Use #CoglSnippet api instead A #CoglHandle for a linked program the uniform location retrieved from cogl_program_get_uniform_location(). The dimensions of the matrix. So for for example pass 2 for a 2x2 matrix or 3 for 3x3. For uniform arrays this is the array length otherwise just pass 1 Whether to transpose the matrix when setting the uniform. the new value of the uniform. Retrieves the type of a shader #CoglHandle Use #CoglSnippet api %COGL_SHADER_TYPE_VERTEX if the shader is a vertex processor or %COGL_SHADER_TYPE_FRAGMENT if the shader is a frament processor #CoglHandle for a shader. Replaces the current source associated with a shader with a new one. Please see <link linkend="cogl-Shaders-and-Programmable-Pipeline.description">above</link> for a description of the recommended format for the shader code. Use #CoglSnippet api #CoglHandle for a shader. Shader source. Adds a callback function that will receive all native events. The function can stop further processing of the event by return %COGL_FILTER_REMOVE. a #CoglRenderer the callback function user data passed to @func when called the foreign Xlib display that will be used by any Xlib based winsys backend. The display needs to be set with cogl_xlib_renderer_set_foreign_display() before this function is called. a #CoglRenderer This function processes a single event; it can be used to hook into external event retrieval (for example that done by Clutter or GDK). #CoglFilterReturn. %COGL_FILTER_REMOVE indicates that Cogl has internally handled the event and the caller should do no further processing. %COGL_FILTER_CONTINUE indicates that Cogl is either not interested in the event, or has used the event to update internal state without taking any exclusive action. a #CoglRenderer pointer to an XEvent structure Removes a callback that was previously added with cogl_xlib_renderer_add_filter(). a #CoglRenderer the callback function user data given when the callback was installed Sets whether Cogl should make use of the NV_robustness_video_memory_purge extension, if exposed by the driver, by initializing the GLX context appropriately. The extension is only useful when running on certain versions of the NVIDIA driver. Quoting from the spec: "The NVIDIA OpenGL driver architecture on Linux has a limitation: resources located in video memory are not persistent across certain events. VT switches, suspend/resume events, and mode switching events may erase the contents of video memory. Any resource that is located exclusively in video memory, such as framebuffer objects (FBOs), will be lost." "This extension provides a way for applications to discover when video memory content has been lost, so that the application can re-populate the video memory content as necessary." "Any driver that exposes this extension is a driver that considers video memory to be volatile. Once the driver stack has been improved, the extension will no longer be exposed." cogl_get_graphics_reset_status() needs to be called at least once every frame to find out if video memory was purged. Note that this doesn't cause Cogl to enable robust buffer access but other context reset errors may still happen and be reported via cogl_get_graphics_reset_status() if external factors cause the driver to trigger them. This defaults to %FALSE and is effective only if called before cogl_display_setup() . a #CoglRenderer The new value Sets a foreign Xlib display that Cogl will use for and Xlib based winsys backend. Note that calling this function will automatically disable Cogl's event retrieval. Cogl still needs to see all of the X events so the application should also use cogl_xlib_renderer_handle_event() if it uses this function. a #CoglRenderer