WebGLProgram

优质
小牛编辑
116浏览
2023-12-01

发送到顶点着色器和片元着色器的GLSL程序的构造函数, 包含默认的变量(uniforms)和属性

内置的变量(uniforms)和属性

顶点着色器(无条件的):

// = object.matrixWorld
uniform mat4 modelMatrix;
// = camera.matrixWorldInverse * object.matrixWorld
uniform mat4 modelViewMatrix;
// = camera.projectionMatrix
uniform mat4 projectionMatrix;
// = camera.matrixWorldInverse
uniform mat4 viewMatrix;
// = inverse transpose of modelViewMatrix
uniform mat3 normalMatrix;
// = camera position in world space
uniform vec3 cameraPosition;
// default vertex attributes provided by Geometry and BufferGeometry
attribute vec3 position;
attribute vec3 normal;
attribute vec2 uv;

注意,可以通过以下方式计算顶点着色器中顶点的位置:

gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );
或者也可以这样:
gl_Position = projectionMatrix * viewMatrix * modelMatrix * vec4( position, 1.0 );

顶点着色器(有条件的):

#if defined( USE_COLOR_ALPHA )
  // vertex color attribute with alpha
  attribute vec4 color;
#elif defined( USE_COLOR )
  // vertex color attribute
  attribute vec3 color;
#endif
#ifdef USE_MORPHTARGETS
  attribute vec3 morphTarget0;
  attribute vec3 morphTarget1;
  attribute vec3 morphTarget2;
  attribute vec3 morphTarget3;
  #ifdef USE_MORPHNORMALS
    attribute vec3 morphNormal0;
    attribute vec3 morphNormal1;
    attribute vec3 morphNormal2;
    attribute vec3 morphNormal3;
  #else
    attribute vec3 morphTarget4;
    attribute vec3 morphTarget5;
    attribute vec3 morphTarget6;
    attribute vec3 morphTarget7;
  #endif
#endif
#ifdef USE_SKINNING
  attribute vec4 skinIndex;
  attribute vec4 skinWeight;
#endif

片元着色器:

uniform mat4 viewMatrix;
uniform vec3 cameraPosition;

构造器

WebGLProgram( renderer : WebGLRenderer, cacheKey : String, parameters : Object )

参数详见WebGLRenderer.

属性

.name : String

The name of the respective shader program.

.id : String

The identifier of this instance.

.cacheKey : String

This key enables the reusability of a single WebGLProgram for different materials.

.usedTimes : Integer

How many times this instance is used for rendering render items.

.program : Object

The actual shader program.

.vertexShader : WebGLShader

An instance of WebGLShader representing the vertex shader.

.fragmentShader : WebGLShader

An instance of WebGLShader representing the frament shader.

方法

.getUniforms () : Object

返回所有活动态的变量(uniform)位置的name-value映射

.getAttributes () : Object

返回所有活动态的顶点属性位置的name-value映射

.destroy () : null

Destroys an instance of WebGLProgram.

源码

src/renderers/webgl/WebGLProgram.js