export declare const luminosity_frag = "\nprecision highp float;\nprecision highp int;\nprecision highp sampler2D;\n\nuniform sampler2D tColor;\nuniform sampler2D tEmissive;\nuniform sampler2D tDepth;\nuniform vec2 uTexSizeInv;\n\nuniform vec3 uDefaultColor;\nuniform float uDefaultOpacity;\nuniform float uLuminosityThreshold;\nuniform float uSmoothWidth;\n\n#include common\n\nfloat getDepth(const in vec2 coords) {\n    #ifdef depthTextureSupport\n        return texture2D(tDepth, coords).r;\n    #else\n        return unpackRGBAToDepth(texture2D(tDepth, coords));\n    #endif\n}\n\nbool isBackground(const in float depth) {\n    return depth == 1.0;\n}\n\nvoid main(void) {\n    vec2 coords = gl_FragCoord.xy * uTexSizeInv;\n    vec4 texel = texture2D(tColor, coords);\n    float emissive = texture2D(tEmissive, coords).a;\n    float depth = getDepth(coords);\n\n    if (isBackground(depth)) {\n        gl_FragColor = vec4(0.0, 0.0, 0.0, 0.0);\n        return;\n    }\n\n    vec4 outputColor = vec4(uDefaultColor.rgb, uDefaultOpacity);\n\n    #if defined(dMode_luminosity)\n        vec3 luma = vec3(0.299, 0.587, 0.114);\n        float v = dot(texel.xyz, luma);\n        float alpha = smoothstep(uLuminosityThreshold, uLuminosityThreshold + uSmoothWidth, v);\n\n        gl_FragColor = mix(outputColor, texel, alpha);\n    #elif defined(dMode_emissive)\n        gl_FragColor = mix(outputColor, texel, emissive);\n    #endif\n}\n";