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playcanvas

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

playcanvas.com

playcanvas/engine

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var shadowEVSM_default = ` fn linstep(a: f32, b: f32, v: f32) -> f32 { return clamp((v - a) / (b - a), 0.0, 1.0); } fn reduceLightBleeding(pMax: f32, amount: f32) -> f32 { return linstep(amount, 1.0, pMax); } fn chebyshevUpperBound(moments: vec2f, mean: f32, minVariance: f32, lightBleedingReduction: f32) -> f32 { var variance: f32 = moments.y - (moments.x * moments.x); variance = max(variance, minVariance); let d: f32 = mean - moments.x; var pMax: f32 = variance / (variance + (d * d)); pMax = reduceLightBleeding(pMax, lightBleedingReduction); return select(pMax, 1.0, mean <= moments.x); } fn calculateEVSM(moments_in: vec3f, Z_in: f32, vsmBias: f32, exponent: f32) -> f32 { let Z: f32 = 2.0 * Z_in - 1.0; let warpedDepth: f32 = exp(exponent * Z); let moments: vec2f = moments_in.xy + vec2f(warpedDepth, warpedDepth*warpedDepth) * (1.0 - moments_in.z); let VSMBias: f32 = vsmBias; let depthScale: f32 = VSMBias * exponent * warpedDepth; let minVariance1: f32 = depthScale * depthScale; return chebyshevUpperBound(moments, warpedDepth, minVariance1, 0.1); } fn VSM16(tex: texture_2d<f32>, texSampler: sampler, texCoords: vec2f, resolution: f32, Z: f32, vsmBias: f32, exponent: f32) -> f32 { let moments: vec3f = textureSampleLevel(tex, texSampler, texCoords, 0.0).xyz; return calculateEVSM(moments, Z, vsmBias, exponent); } fn getShadowVSM16(shadowMap: texture_2d<f32>, shadowMapSampler: sampler, shadowCoord: vec3f, shadowParams: vec4f, exponent: f32) -> f32 { return VSM16(shadowMap, shadowMapSampler, shadowCoord.xy, shadowParams.x, shadowCoord.z, shadowParams.y, exponent); } fn getShadowSpotVSM16(shadowMap: texture_2d<f32>, shadowMapSampler: sampler, shadowCoord: vec3f, shadowParams: vec4f, exponent: f32, lightDir: vec3f) -> f32 { let Z: f32 = length(lightDir) * shadowParams.w + shadowParams.z; return VSM16(shadowMap, shadowMapSampler, shadowCoord.xy, shadowParams.x, Z, shadowParams.y, exponent); } fn VSM32(tex: texture_2d<f32>, texSampler: sampler, texCoords_in: vec2f, resolution: f32, Z: f32, vsmBias: f32, exponent: f32) -> f32 { #ifdef CAPS_TEXTURE_FLOAT_FILTERABLE var moments: vec3f = textureSampleLevel(tex, texSampler, texCoords_in, 0.0).xyz; #else var pixelSize : f32 = 1.0 / resolution; let texCoords: vec2f = texCoords_in - vec2f(pixelSize); let s00: vec3f = textureSampleLevel(tex, texSampler, texCoords, 0.0).xyz; let s10: vec3f = textureSampleLevel(tex, texSampler, texCoords + vec2f(pixelSize, 0.0), 0.0).xyz; let s01: vec3f = textureSampleLevel(tex, texSampler, texCoords + vec2f(0.0, pixelSize), 0.0).xyz; let s11: vec3f = textureSampleLevel(tex, texSampler, texCoords + vec2f(pixelSize), 0.0).xyz; let fr: vec2f = fract(texCoords * resolution); let h0: vec3f = mix(s00, s10, fr.x); let h1: vec3f = mix(s01, s11, fr.x); var moments: vec3f = mix(h0, h1, fr.y); #endif return calculateEVSM(moments, Z, vsmBias, exponent); } fn getShadowVSM32(shadowMap: texture_2d<f32>, shadowMapSampler: sampler, shadowCoord: vec3f, shadowParams: vec4f, exponent: f32) -> f32 { return VSM32(shadowMap, shadowMapSampler, shadowCoord.xy, shadowParams.x, shadowCoord.z, shadowParams.y, exponent); } fn getShadowSpotVSM32(shadowMap: texture_2d<f32>, shadowMapSampler: sampler, shadowCoord: vec3f, shadowParams: vec4f, exponent: f32, lightDir: vec3f) -> f32 { let Z: f32 = length(lightDir) * shadowParams.w + shadowParams.z; return VSM32(shadowMap, shadowMapSampler, shadowCoord.xy, shadowParams.x, Z, shadowParams.y, exponent); } `; export { shadowEVSM_default as default };