Photometric function Three.js

Question

Does anyone know how to define a photometric function in Three.js?

At the moment I'm using a Lambert

new THREE.MeshLambertMaterial({ color: 0xffffff }) 

But I want to use a Lommel Seeliger and I don't know where and how to define it.

Answer 1

You'll have to write a custom fragment shader for this purpose. You can take a look near the bottom of this page for a sample implementation of a Lommel-Seeliger shader.

Within Three.js, use a ShaderMaterial to apply your shader. A nice introduction to the concept is this tutorial , basically you do

var shaderMaterial =
  new THREE.ShaderMaterial({
    vertexShader:   vertexShader,
    fragmentShader: fragmentShader
  });