/** Name of engine */
export declare const engineName = "LittleJS";
/** Version of engine */
export declare const engineVersion = "1.1.2";
/** Frames per second to update objects
 *  @default */
export declare const FPS = 60;
/** How many seconds each frame lasts, engine uses a fixed time step
 *  @default 1/60 */
export declare const timeDelta: number;
/** Array containing all engine objects */
export declare let engineObjects: any;
/** Array containing only objects that are set to collide with other objects (for optimization) */
export declare let engineCollideObjects: any;
/** Current update frame, used to calculate time */
export declare let frame: number;
/** Current engine time since start in seconds, derived from frame */
export declare let time: number;
/** Actual clock time since start in seconds (not affected by pause or frame rate clamping) */
export declare let timeReal: number;
/** Is the game paused? Causes time and objects to not be updated. */
export declare let paused: number;
export declare let frameTimeLastMS: number, frameTimeBufferMS: number, debugFPS: number, shrinkTilesX: number, shrinkTilesY: number, drawCount: any, tileImageSize: any, tileImageSizeInverse: any;
export declare function setDrawCount(count: number): number;
/** Start up LittleJS engine with your callback functions
 *  @param {Function} gameInit       - Called once after the engine starts up, setup the game
 *  @param {Function} gameUpdate     - Called every frame at 60 frames per second, handle input and update the game state
 *  @param {Function} gameUpdatePost - Called after physics and objects are updated, setup camera and prepare for render
 *  @param {Function} gameRender     - Called before objects are rendered, draw any background effects that appear behind objects
 *  @param {Function} gameRenderPost - Called after objects are rendered, draw effects or hud that appear above all objects
 *  @param {String} tileImageSource  - Tile image to use, everything starts when the image is finished loading
 */
export declare function engineInit(gameInit: any, gameUpdate: any, gameUpdatePost: any, gameRender: any, gameRenderPost: any, tileImageSource: any): void;
/** Calls update on each engine object (recursively if child), removes destroyed objects, and updated time */
export declare function engineObjectsUpdate(): void;
/** Detroy and remove all objects that are not persistent or descendants of a persistent object */
export declare function engineObjectsDestroy(): void;
/** Triggers a callback for each object within a given area
 *  @param {Vector2} [pos] - Center of test area
 *  @param {Number} [size] - Radius of circle if float, rectangle size if Vector2
 *  @param {Function} [callbackFunction] - Calls this function on every object that passes the test
 *  @param {Array} [objects=engineObjects] - List of objects to check */
export declare function engineObjectsCallback(pos: any, size: any, callbackFunction: any, objects?: any): void;