Question

我注意到THREE.js在内部使用着色器来创建核心材料＆＃34;例如。 MeshLambertMaterial＆＃34;，所以我决定将Lambert着色器从Three.js代码复制到一个新的着色器中并在其上构建。

这是我得到的代码（忠实地从Three.js r66复制）

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")

}

这是我用来设置制服并创建材料的代码。

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
                });

问题是，当我使用这些参数创建一个MeshLambertMaterial时，我得到了正确的光照和纹理重复，当我用它来创建ShaderMaterial时，灯光和阴影似乎正在工作，但纹理贴图没有被加载为了解决这个问题，我挖掘了代码并设法通过添加这个丑陋的＆＃34; hack＆＃34;来加载地图。到我的代码，在材料定义之后

material.map = true;

现在加载并显示纹理，但看起来纹理坐标混乱，而不是重复，Shader似乎忽略了我提供的重复值。

为什么我需要那个黑客来处理我的纹理，我该怎么做才能获得正确的纹理重复？

Answer 1

three.js设计易于使用，不易修改。这可能会在未来改变......

您需要设置material.defines，如此：

var defines = {};

defines[ "USE_MAP" ] = "";.

然后在材质构造函数中指定defines。

var material =  new THREE.ShaderMaterial({
   name: "TerrainShader",
   defines     : defines,
   uniforms    : shaderUniforms,
   vertexShader: THREE.MyShader.vertexShader,
   fragmentShader: THREE.MyShader.fragmentShader,
   fog:false,
   lights:true
});

关于纹理重复，您需要将重复添加到制服中：

shaderUniforms[ "offsetRepeat" ].value.set( 0, 0, 2, 2 );

three.js r.66

复制MeshLambertMaterial使用ShaderMaterial忽略纹理

1 个答案: