playcanvas
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PlayCanvas WebGL game engine
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JavaScript
var shadowEVSMPS = "\nfloat linstep(float a, float b, float v) {\n return saturate((v - a) / (b - a));\n}\nfloat reduceLightBleeding(float pMax, float amount) {\n return linstep(amount, 1.0, pMax);\n}\nfloat chebyshevUpperBound(vec2 moments, float mean, float minVariance, float lightBleedingReduction) {\n float variance = moments.y - (moments.x * moments.x);\n variance = max(variance, minVariance);\n float d = mean - moments.x;\n float pMax = variance / (variance + (d * d));\n pMax = reduceLightBleeding(pMax, lightBleedingReduction);\n return (mean <= moments.x ? 1.0 : pMax);\n}\nfloat calculateEVSM(vec3 moments, float Z, float vsmBias, float exponent) {\n Z = 2.0 * Z - 1.0;\n float warpedDepth = exp(exponent * Z);\n moments.xy += vec2(warpedDepth, warpedDepth*warpedDepth) * (1.0 - moments.z);\n float VSMBias = vsmBias;\n float depthScale = VSMBias * exponent * warpedDepth;\n float minVariance1 = depthScale * depthScale;\n return chebyshevUpperBound(moments.xy, warpedDepth, minVariance1, 0.1);\n}\nfloat VSM16(TEXTURE_ACCEPT(tex), vec2 texCoords, float resolution, float Z, float vsmBias, float exponent) {\n vec3 moments = texture2DLod(tex, texCoords, 0.0).xyz;\n return calculateEVSM(moments, Z, vsmBias, exponent);\n}\nfloat getShadowVSM16(TEXTURE_ACCEPT(shadowMap), vec3 shadowCoord, vec4 shadowParams, float exponent) {\n return VSM16(TEXTURE_PASS(shadowMap), shadowCoord.xy, shadowParams.x, shadowCoord.z, shadowParams.y, exponent);\n}\nfloat getShadowSpotVSM16(TEXTURE_ACCEPT(shadowMap), vec3 shadowCoord, vec4 shadowParams, float exponent, vec3 lightDir) {\n return VSM16(TEXTURE_PASS(shadowMap), shadowCoord.xy, shadowParams.x, length(lightDir) * shadowParams.w + shadowParams.z, shadowParams.y, exponent);\n}\nfloat VSM32(TEXTURE_ACCEPT(tex), vec2 texCoords, float resolution, float Z, float vsmBias, float exponent) {\n #ifdef CAPS_TEXTURE_FLOAT_FILTERABLE\n vec3 moments = texture2DLod(tex, texCoords, 0.0).xyz;\n #else\n float pixelSize = 1.0 / resolution;\n texCoords -= vec2(pixelSize);\n vec3 s00 = texture2DLod(tex, texCoords, 0.0).xyz;\n vec3 s10 = texture2DLod(tex, texCoords + vec2(pixelSize, 0), 0.0).xyz;\n vec3 s01 = texture2DLod(tex, texCoords + vec2(0, pixelSize), 0.0).xyz;\n vec3 s11 = texture2DLod(tex, texCoords + vec2(pixelSize), 0.0).xyz;\n vec2 fr = fract(texCoords * resolution);\n vec3 h0 = mix(s00, s10, fr.x);\n vec3 h1 = mix(s01, s11, fr.x);\n vec3 moments = mix(h0, h1, fr.y);\n #endif\n return calculateEVSM(moments, Z, vsmBias, exponent);\n}\nfloat getShadowVSM32(TEXTURE_ACCEPT(shadowMap), vec3 shadowCoord, vec4 shadowParams, float exponent) {\n return VSM32(TEXTURE_PASS(shadowMap), shadowCoord.xy, shadowParams.x, shadowCoord.z, shadowParams.y, exponent);\n}\nfloat getShadowSpotVSM32(TEXTURE_ACCEPT(shadowMap), vec3 shadowCoord, vec4 shadowParams, float exponent, vec3 lightDir) {\n return VSM32(TEXTURE_PASS(shadowMap), shadowCoord.xy, shadowParams.x, length(lightDir) * shadowParams.w + shadowParams.z, shadowParams.y, exponent);\n}\n";
export { shadowEVSMPS as default };