  ## burley (`lygia`/`lighting`/`diffuse`/`burley`)

calculate diffuse contribution using burley equation

Dependencies:

Use:

``````<float> diffuseBurley(<vec3> light, <vec3> normal [, <vec3> view, <float> roughness] )
``````
``````<float> diffuseBurley(<vec3> L, <vec3> N, <vec3> V, <float> NoV, <float> NoL, <float> roughness)
``````

Check it on Github

``````

#ifndef FNC_DIFFUSE_BURLEY
#define FNC_DIFFUSE_BURLEY

float diffuseBurley(const in float NoV, const in float NoL, const in float LoH, const in float linearRoughness) {
// Burley 2012, "Physically-Based Shading at Disney"
float f90 = 0.5 + 2.0 * linearRoughness * LoH * LoH;
float lightScatter = schlick(1.0, f90, NoL);
float viewScatter  = schlick(1.0, f90, NoV);
return lightScatter * viewScatter;
}

float diffuseBurley(const in vec3 L, const in vec3 N, const in vec3 V, const in float NoV, const in float NoL, const in float roughness) {
float LoH = max(dot(L, normalize(L + V)), 0.001);
return diffuseBurley(NoV, NoL, LoH, roughness * roughness);
}

float diffuseBurley(const in vec3 L, const in vec3 N, const in vec3 V, const in float roughness) {
vec3 H = normalize(V + L);
float NoV = clamp(dot(N, V), 0.001, 1.0);
float NoL = clamp(dot(N, L), 0.001, 1.0);
float LoH = clamp(dot(L, H), 0.001, 1.0);

return diffuseBurley(NoV, NoL, LoH, roughness * roughness);
}

#endif
``````

Dependencies:

Use:

``````<float> diffuseBurley(<float3> light, <float3> normal [, <float3> view, <float> roughness] )
``````
``````<float> diffuseBurley(<float3> L, <float3> N, <float3> V, <float> NoV, <float> NoL, <float> roughness)
``````

Check it on Github

``````

#ifndef FNC_DIFFUSE_BURLEY
#define FNC_DIFFUSE_BURLEY

float diffuseBurley(float NoV, float NoL, float LoH, float linearRoughness) {
// Burley 2012, "Physically-Based Shading at Disney"
float f90 = 0.5 + 2.0 * linearRoughness * LoH * LoH;
float lightScatter = schlick(1.0, f90, NoL);
float viewScatter  = schlick(1.0, f90, NoV);
return lightScatter * viewScatter;
}

float diffuseBurley(float3 L, float3 N, float3 V, float NoV, float NoL, float roughness) {
float LoH = max(dot(L, normalize(L + V)), 0.001);
return diffuseBurley(NoV, NoL, LoH, roughness * roughness);
}

float diffuseBurley(float3 L, float3 N, float3 V, float roughness) {
float3 H = normalize(V + L);
float NoV = clamp(dot(N, V), 0.001, 1.0);
float NoL = clamp(dot(N, L), 0.001, 1.0);
float LoH = clamp(dot(L, H), 0.001, 1.0);

return diffuseBurley(NoV, NoL, LoH, roughness * roughness);
}

#endif
``````