LYGIA Shader Library

Dependencies:

• lygia/lighting/common/ggx.glsl
• lygia/lighting/common/smithGGXCorrelated.glsl
• lygia/math/saturate.glsl
• lygia/math/saturateMediump.glsl
• lygia/lighting/fresnel.glsl

Check it on Github

#ifndef FNC_SPECULAR_COOKTORRANCE
#define FNC_SPECULAR_COOKTORRANCE

vec3 specularCookTorrance(const in vec3 L, const in vec3 N, const in vec3 H, const in float NoV, const in float NoL, const in float NoH, const in float linearRoughness, const in vec3 specularColor) {
    float LoH = saturate(dot(L, H));

    float D = GGX(N, H, NoH, linearRoughness);

#if defined(PLATFORM_RPI)
    float V = smithGGXCorrelated_Fast(NoV, NoL, linearRoughness);
#else
    float V = smithGGXCorrelated(NoV, NoL,linearRoughness);
#endif

    vec3 F = fresnel(specularColor, LoH);

    return (D * V) * F;
}

vec3 specularCookTorrance(ShadingData shadingData){
    return specularCookTorrance(shadingData.L, shadingData.N, shadingData.H, shadingData.NoV, shadingData.NoL, shadingData.NoH, shadingData.linearRoughness, shadingData.specularColor); 
}


#endif

Dependencies:

• lygia/lighting/common/ggx.glsl
• lygia/lighting/common/smithGGXCorrelated.glsl
• lygia/math/saturateMediump.glsl
• lygia/lighting/fresnel.glsl

Check it on Github

#ifndef FNC_SPECULAR_COOKTORRANCE
#define FNC_SPECULAR_COOKTORRANCE

float3 specularCookTorrance(float3 L, float3 N, const in float3 H, float NoV, float NoL, const in float NoH, float linearRoughness, float3 specularColor) {
    float LoH = saturate(dot(L, H));

    float D = GGX(N, H, NoH, linearRoughness);

#if defined(PLATFORM_RPI)
    float V = smithGGXCorrelated_Fast(NoV, NoL, linearRoughness);
#else
    float V = smithGGXCorrelated(NoV, NoL, linearRoughness);
#endif

    float3 F = fresnel(specularColor, LoH);

    return (D * V) * F;
}

float3 specularCookTorrance(ShadingData shadingData){
    return specularCookTorrance(shadingData.L, shadingData.N, shadingData.H, shadingData.NoV, shadingData.NoL, shadingData.NoH, shadingData.linearRoughness, shadingData.specularColor);
}

#endif

Dependencies:

• lygia/lighting/common/ggx.glsl

Check it on Github

fn specularCookTorrance(L: vec3f, N: vec3f, V: vec3f, NoV: f32, NoL: f32, roughness: f32, fresnel: f32) -> f32 {
    // Half angle vector
    let H = normalize(L + V);

    // Geometric term
    let NoH = max(dot(N, H), 0.0);
    let VoH = max(dot(V, H), 0.000001);

    let x = 2.0 * NoH / VoH;
    let G = min(1.0, min(x * NoV, x * NoL));

    // Distribution term
    let D = GGX(N, H, NoH, roughness);

    // Fresnel term
    let F = pow(1.0 - NoV, fresnel);

    // Multiply terms and done
    return max(G * F * D / max(PI * NoV * NoL, 0.00001), 0.0);
}