playcanvas/build/playcanvas/src/scene/shader-lib/glsl/chunks/render-pass/frag/taaResolve.d.ts

Open-source WebGL/WebGPU 3D engine for the web

declare const _default: "\n    #include  \"sampleCatmullRomPS\"\n    #include  \"screenDepthPS\"\n\n    uniform sampler2D sourceTexture;\n    uniform sampler2D historyTexture;\n    uniform mat4 matrix_viewProjectionPrevious;\n    uniform mat4 matrix_viewProjectionInverse;\n    uniform vec4 jitters;   // xy: current frame, zw: previous frame\n    uniform vec2 textureSize;\n\n    varying vec2 uv0;\n\n    vec2 reproject(vec2 uv, float depth) {\n\n        // fragment NDC\n        depth = depth * 2.0 - 1.0;\n        vec4 ndc = vec4(uv * 2.0 - 1.0, depth, 1.0);\n\n        // remove jitter from the current frame\n        ndc.xy -= jitters.xy;\n\n        // Transform NDC to world space of the current frame\n        vec4 worldPosition = matrix_viewProjectionInverse * ndc;\n        worldPosition /= worldPosition.w;\n\n        // world position to screen space of the previous frame\n        vec4 screenPrevious = matrix_viewProjectionPrevious * worldPosition;\n\n        return (screenPrevious.xy / screenPrevious.w) * 0.5 + 0.5;\n    }\n\n    vec3 colorClampPremul(vec2 uv, vec3 historyPremul) {\n\n        vec3 minPremul = vec3(9999.0);\n        vec3 maxPremul = vec3(-9999.0);\n\n        // 3x3 neighborhood in premultiplied space \u2014 same domain as the temporal mix (see main()).\n        for(float x = -1.0; x <= 1.0; ++x) {\n            for(float y = -1.0; y <= 1.0; ++y) {\n                vec4 s = texture2D(sourceTexture, uv + vec2(x, y) / textureSize);\n                vec3 premul = s.rgb * s.a;\n                minPremul = min(minPremul, premul);\n                maxPremul = max(maxPremul, premul);\n            }\n        }\n\n        return clamp(historyPremul, minPremul, maxPremul);\n    }\n\n    void main()\n    {\n        // current frame\n        vec4 srcColor = texture2D(sourceTexture, uv0);\n\n        // current depth is in linear space, convert it to non-linear space\n        float linearDepth = getLinearScreenDepth(uv0);\n        float depth = delinearizeDepth(linearDepth);\n\n        // previous frame\n        vec2 historyUv = reproject(uv0, depth);\n\n        #ifdef QUALITY_HIGH\n\n            vec4 historySample = SampleTextureCatmullRom(TEXTURE_PASS(historyTexture), historyUv, textureSize);\n\n        #else\n\n            vec4 historySample = texture2D(historyTexture, historyUv);\n\n        #endif\n\n        // Premultiplied (rgb * a) is the coverage-correct space for TAA: straight RGB interpolates\n        // uncorrelated color and opacity at edges, which causes colored fringes and alpha-related\n        // ghosting when history is blended or clamped against a 3x3 neighborhood. We clamp and mix\n        // in premultiplied space, then un-premultiply once using the current frame's alpha only\n        // (alpha is not temporally filtered \u2014 output stays tied to this frame's coverage).\n        vec3 historyPremul = historySample.rgb * historySample.a;\n        vec3 srcPremul = srcColor.rgb * srcColor.a;\n\n        vec3 historyPremulClamped = colorClampPremul(uv0, historyPremul);\n\n        float mixFactor = (historyUv.x < 0.0 || historyUv.x > 1.0 || historyUv.y < 0.0 || historyUv.y > 1.0) ?\n            1.0 : 0.05;\n\n        vec3 mixedPremul = mix(historyPremulClamped, srcPremul, mixFactor);\n        float a = srcColor.a;\n        // Match UNORM8 alpha quantum: below one step, un-premul is ill-defined / noisy; use current RGB.\n        const float UNPREMUL_EPS = 1.0 / 255.0;\n        vec3 rgbStraight = (a > UNPREMUL_EPS) ? (mixedPremul / a) : srcColor.rgb;\n        gl_FragColor = vec4(rgbStraight, a);\n    }\n";
export default _default;