Oren-Nayar diffuse lighting model
npm install glsl-diffuse-oren-nayarThe Oren-Nayar diffuse lighting model implemented in GLSL.
``glsl
#pragma glslify: orenNayar = require(glsl-diffuse-orenNayar)
uniform vec3 lightPosition, eyePosition;
varying vec3 surfacePosition, surfaceNormal;
void main() {
//Light and view geometry
vec3 lightDirection = normalize(lightPosition - surfacePosition);
vec3 viewDirection = normalize(eyePosition - surfacePosition);
//Surface properties
vec3 normal = normalize(surfaceNormal);
//Compute diffuse light intensity
float power = orenNayar(
lightDirection,
viewDirection,
normal,
0.3,
0.7);
gl_FragColor = vec4(power,power,power,1.0);
}
`
Install with npm:
`
npm install glsl-diffuse-oren-nayar
Then use with glslify.
`glsl`
#pragma glslify: orenNayar = require(glsl-diffuse-oren-nayar)
##### float orenNayar(vec3 lightDir, vec3 viewDir, vec3 normal, float roughness, float albedo)
Computes the diffuse intensity in the Lambertian model
lightDir is a unit length* vec3 pointing from the surface point toward the lightviewDir
is a unit length* vec3 pointing toward the cameranormal
is the unit length* surface normal at the sample pointroughness
* is a parameter between 0 and 1 measuring the surface roughness. 0 for smooth, 1 for mattealbedo
* measures the intensity of the diffuse reflection. Values >0.96 do not conserve energy
Returns A float` representing the diffuse light intensity