#if defined(TARGET_MOBILE)
#define MIN_PERCEPTUAL_ROUGHNESS 0.089
#define MIN_ROUGHNESS            0.007921
#else
#define MIN_PERCEPTUAL_ROUGHNESS 0.045
#define MIN_ROUGHNESS            0.002025
#endif
#define MIN_N_DOT_V 1e-4
float clampNoV(float NoV) {
return max(NoV, MIN_N_DOT_V);
}
vec3 computeDiffuseColor(const vec4 baseColor, float metallic) {
return baseColor.rgb * (1.0 - metallic);
}
vec3 computeF0(const vec4 baseColor, float metallic, float reflectance) {
return baseColor.rgb * metallic + (reflectance * (1.0 - metallic));
}
float computeDielectricF0(float reflectance) {
return 0.16 * reflectance * reflectance;
}
float computeMetallicFromSpecularColor(const vec3 specularColor) {
return max3(specularColor);
}
float computeRoughnessFromGlossiness(float glossiness) {
return 1.0 - glossiness;
}
float perceptualRoughnessToRoughness(float perceptualRoughness) {
return perceptualRoughness * perceptualRoughness;
}
float roughnessToPerceptualRoughness(float roughness) {
return sqrt(roughness);
}
float iorToF0(float transmittedIor, float incidentIor) {
return sq((transmittedIor - incidentIor) / (transmittedIor + incidentIor));
}
float f0ToIor(float f0) {
float r = sqrt(f0);
return (1.0 + r) / (1.0 - r);
}
vec3 f0ClearCoatToSurface(const vec3 f0) {
#if FILAMENT_QUALITY == FILAMENT_QUALITY_LOW
return saturate(f0 * (f0 * 0.526868 + 0.529324) - 0.0482256);
#else
return saturate(f0 * (f0 * (0.941892 - 0.263008 * f0) + 0.346479) - 0.0285998);
#endif
}