glsl-specular-ward

Computes the anisotropic specularity in the Ward model

Example

``glsl #pragma glslify: wardSpec = require(glsl-specular-ward)

uniform vec3 eyePosition; uniform vec3 lightPosition;

uniform float shinyPar, shinyPerp;

varying vec3 surfacePosition; varying vec3 surfaceNormal; varying vec3 fiberDirection;

void main() { //Light and view geometry vec3 eyeDirection = normalize(eyePosition - surfacePosition); vec3 lightDirection = normalize(lightPosition - surfacePosition);

//Surface properties vec3 normal = normalize(surfaceNormal); vec3 fiberPar = normalize(fiberDirection); vec3 fiberPerp = normalize(cross(surfaceNormal, fiberDirection));

//Compute specular power float power = wardSpec( lightDirection, viewDirection, normal, fiberPar, fiberPerp, shinyPar, shinyPerp);

gl_FragColor = vec4(power,power,power,1.0); }`

`Usage`

Install with npm:

`npm install glsl-specular-phong`

Then use with glslify.

`API`

`glsl #pragma glslify: ward = require(glsl-specular-ward)`

##### float ward(vec3 lightDir, vec3 eyeDir, vec3 normal, vec3 fiberParallel, vec3 fiberPerpendicular, float shinyParallel, float shinyPerpendicular)Computes the specular power in the Phong lighting model.

lightDir is a unit length* vec3pointing from the surface point toward the lighteyeDir is a unit length* vec3pointing from the surface point toward the cameranormal is the unit length* surface normal at the sample pointfiberParallel is a unit length* vector tangent to the surface aligned with the local fiber orientationfiberPerpendicular is a unit length* vector tangent to surface aligned with the local fiber orientation *shinyParallelis the roughness of the fibers in the parallel direction *shinyPerpendicular is the roughness of the fibers in perpendicular direction

Returns A float` representing the specular power

License

Example

glsl
#pragma glslify: wardSpec = require(glsl-specular-ward)

uniform vec3 eyePosition;
uniform vec3 lightPosition;

uniform float shinyPar, shinyPerp;

varying vec3 surfacePosition;
varying vec3 surfaceNormal;
varying vec3 fiberDirection;

void main() {
  //Light and view geometry
  vec3 eyeDirection = normalize(eyePosition - surfacePosition);
  vec3 lightDirection = normalize(lightPosition - surfacePosition);

  //Surface properties
  vec3 normal = normalize(surfaceNormal);
  vec3 fiberPar = normalize(fiberDirection);
  vec3 fiberPerp = normalize(cross(surfaceNormal, fiberDirection));

  //Compute specular power
  float power = wardSpec(
    lightDirection, 
    viewDirection, 
    normal, 
    fiberPar,
    fiberPerp,
    shinyPar,
    shinyPerp);

  gl_FragColor = vec4(power,power,power,1.0);
}

API

glsl
#pragma glslify: ward = require(glsl-specular-ward)

##### float ward(vec3 lightDir, vec3 eyeDir, vec3 normal, vec3 fiberParallel, vec3 fiberPerpendicular, float shinyParallel, float shinyPerpendicular)


Computes the specular power in the Phong lighting model.

lightDir is a unit length* vec3

 pointing from the surface point toward the light

eyeDir is a unit length* vec3

 pointing from the surface point toward the camera

normal is the

unit length* surface normal at the sample point

fiberParallel is a

unit length* vector tangent to the surface aligned with the local fiber orientation

fiberPerpendicular is a

unit length* vector tangent to surface aligned with the local fiber orientation
*

shinyParallel

 is the roughness of the fibers in the parallel direction
*

shinyPerpendicular is the roughness of the fibers in perpendicular direction

Returns A float` representing the specular power