26 lines
No EOL
871 B
GLSL
26 lines
No EOL
871 B
GLSL
#ifndef FNC_SPECULAR_WARD
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#define FNC_SPECULAR_WARD
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// https://github.com/glslify/glsl-specular-ward
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float specularWard(const in vec3 L, const in vec3 N, const in vec3 V, const in vec3 fiber, const in float shinyParallel, const in float shinyPerpendicular) {
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float NdotL = dot(N, L);
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float NdotR = dot(N, V);
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vec3 fiberParallel = normalize(fiber);
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vec3 fiberPerpendicular = normalize(cross(N, fiber));
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if (NdotL < 0.0 || NdotR < 0.0)
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return 0.0;
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vec3 H = normalize(L + V);
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float NdotH = dot(N, H);
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float XdotH = dot(fiberParallel, H);
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float YdotH = dot(fiberPerpendicular, H);
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float coeff = sqrt(NdotL/NdotR) / (12.5663706144 * shinyParallel * shinyPerpendicular);
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float theta = (pow(XdotH/shinyParallel, 2.0) + pow(YdotH/shinyPerpendicular, 2.0)) / (1.0 + NdotH);
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return coeff * exp(-2.0 * theta);
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}
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#endif |