Replicating MeshLambertMaterial Using ShaderMaterial ignores textures
I noticed that THREE.js uses shaders internally to create core material "e.g. MeshLambertMaterial", So I decided to copy the lambert shader from Three.js code into a new shader and build on it.
This is the code I got (Copied faithfully from Three.js r66)
THREE.MyShader = {
uniforms: THREE.UniformsUtils.merge( [
THREE.UniformsLib[ "common" ],
THREE.UniformsLib[ "fog" ],
THREE.UniformsLib[ "lights" ],
THREE.UniformsLib[ "shadowmap" ],
{
"ambient" : { type: "c", value: new THREE.Color( 0xffffff ) },
"emissive" : { type: "c", value: new THREE.Color( 0x000000 ) },
"wrapRGB" : { type: "v3", value: new THREE.Vector3( 1, 1, 1 ) }
}
]),
vertexShader: [
"#define LAMBERT",
"varying vec3 vLightFront;",
"#ifdef DOUBLE_SIDED",
"varying vec3 vLightBack;",
"#endif",
THREE.ShaderChunk[ "map_pars_vertex" ],
THREE.ShaderChunk[ "lightmap_pars_vertex" ],
THREE.ShaderChunk[ "envmap_pars_vertex" ],
THREE.ShaderChunk[ "lights_lambert_pars_vertex" ],
THREE.ShaderChunk[ "color_pars_vertex" ],
THREE.ShaderChunk[ "morphtarget_pars_vertex" ],
THREE.ShaderChunk[ "skinning_pars_vertex" ],
THREE.ShaderChunk[ "shadowmap_pars_vertex" ],
"void main() {",
THREE.ShaderChunk[ "map_vertex" ],
THREE.ShaderChunk[ "lightmap_vertex" ],
THREE.ShaderChunk[ "color_vertex" ],
THREE.ShaderChunk[ "morphnormal_vertex" ],
THREE.ShaderChunk[ "skinbase_vertex" ],
THREE.ShaderChunk[ "skinnormal_vertex" ],
THREE.ShaderChunk[ "defaultnormal_vertex" ],
THREE.ShaderChunk[ "morphtarget_vertex" ],
THREE.ShaderChunk[ "skinning_vertex" ],
THREE.ShaderChunk[ "default_vertex" ],
THREE.ShaderChunk[ "worldpos_vertex" ],
THREE.ShaderChunk[ "envmap_vertex" ],
THREE.ShaderChunk[ "lights_lambert_vertex" ],
THREE.ShaderChunk[ "shadowmap_vertex" ],
"}"
].join("\n"),
fragmentShader: [
"uniform float opacity;",
"varying vec3 vLightFront;",
"#ifdef DOUBLE_SIDED",
"varying vec3 vLightBack;",
"#endif",
THREE.ShaderChunk[ "color_pars_fragment" ],
THREE.ShaderChunk[ "map_pars_fragment" ],
THREE.ShaderChunk[ "lightmap_pars_fragment" ],
THREE.ShaderChunk[ "envmap_pars_fragment" ],
THREE.ShaderChunk[ "fog_pars_fragment" ],
THREE.ShaderChunk[ "shadowmap_pars_fragment" ],
THREE.ShaderChunk[ "specularmap_pars_fragment" ],
"void main() {",
"gl_FragColor = vec4( vec3 ( 1.0 ), opacity );",
THREE.ShaderChunk[ "map_fragment" ],
THREE.ShaderChunk[ "alphatest_fragment" ],
THREE.ShaderChunk[ "specularmap_fragment" ],
"#ifdef DOUBLE_SIDED",
//"float isFront = float( gl_FrontFacing );",
//"gl_FragColor.xyz *= isFront * vLightFront + ( 1.0 - isFront ) * vLightBack;",
"if ( gl_FrontFacing )",
"gl_FragColor.xyz *= vLightFront;",
"else",
"gl_FragColor.xyz *= vLightBack;",
"#else",
"gl_FragColor.xyz *= vLightFront;",
"#endif",
THREE.ShaderChunk[ "lightmap_fragment" ],
THREE.ShaderChunk[ "color_fragment" ],
THREE.ShaderChunk[ "envmap_fragment" ],
THREE.ShaderChunk[ "shadowmap_fragment" ],
THREE.ShaderChunk[ "linear_to_gamma_fragment" ],
THREE.ShaderChunk[ "fog_fragment" ],
"}"
].join("\n")
}
and this is the code that I use to setup my uniforms and create the material.
var textureUsed = 'rock_1';
var texture = THREE.ImageUtils.loadTexture( texturePath + textureUsed + "/diffuse.png");
texture.wrapS = THREE.RepeatWrapping;
texture.wrapT = THREE.RepeatWrapping;
texture.repeat.x = 128;
texture.repeat.y = 128;
var shaderUniforms = THREE.UniformsUtils.clone( THREE.MyShader.uniforms );
shaderUniforms[ "map" ].value = texture;
var material = new THREE.ShaderMaterial({
name: "TerrainShader",
uniforms : shaderUniforms,
vertexShader: THREE.MyShader.vertexShader,
fragmentShader: THREE.MyShader.fragmentShader,
fog:false,
lights:true
});
The problem is that when I use these parameters to create a MeshLambertMaterial I get the correct lighting and texture repetitions, when I use it to create ShaderMaterial the lights and shadows seem to be working but the texture map isn't loaded, to fix this I dug through the code and managed to get the map to load by adding this ugly "hack" to my code, right after the material definition
material.map = true;
Now the texture is loaded and displayed but it looks like the texture coordinates are messed up, instead of repeating, the Shader seems to be ignoring the repeat values I supplied.
Why did I need that hack to get my texture processed and what can I do to get the correct texture repetitions?
three.js was designed to be easy to use, not easy to modify. This may change in the future...
You need to set the material.defines
like so:
var defines = {};
defines[ "USE_MAP" ] = "";.
Then specify defines
in the material constructor.
var material = new THREE.ShaderMaterial({
name: "TerrainShader",
defines : defines,
uniforms : shaderUniforms,
vertexShader: THREE.MyShader.vertexShader,
fragmentShader: THREE.MyShader.fragmentShader,
fog:false,
lights:true
});
Regarding the texture repetitions, you need to add the repeat to your uniforms:
shaderUniforms[ "offsetRepeat" ].value.set( 0, 0, 2, 2 );
three.js r.66