RFC - support KHR_parallel_shader_compile

docs/api/en/renderers/WebGLRenderer.html

@@ -134,6 +134,7 @@ <h3>[property:Object capabilities]</h3>
 		   The number of textures that can be used in a vertex shader.<br />
 		- [page:Integer maxVertexUniforms]: The value of *gl.MAX_VERTEX_UNIFORM_VECTORS*.
 		   The maximum number of uniforms that can be used in a vertex shader.<br />
+		- [page:Boolean parallelShaderCompile]: whether the context supports the [link:https://www.khronos.org/registry/webgl/extensions/KHR_parallel_shader_compile/ KHR_parallel_shader_compile] extension..<br />
 		- [page:String precision]: The shader precision currently being used by the renderer.<br />
 		- [page:Boolean vertexTextures]: *true* if [property:Integer maxVertexTextures] is greater than 0 (i.e. vertext textures can be used).<br />
 		</p>

docs/api/zh/renderers/WebGLRenderer.html

@@ -115,6 +115,7 @@ <h3>[property:Object capabilities]</h3>
 		- [page:Integer maxVaryings]: *gl.MAX_VARYING_VECTORS*的值，着色器可使用矢量的数量<br />
 		- [page:Integer maxVertexTextures]: *gl.MAX_VERTEX_TEXTURE_IMAGE_UNITS*的值，顶点着色器可使用的纹理数量。<br />
 		- [page:Integer maxVertexUniforms]: *gl.MAX_VERTEX_UNIFORM_VECTORS*的值，顶点着色器可使用的全局变量(uniforms)数量<br />
+		- [page:Boolean parallelShaderCompile]: whether the context supports the [link:https://www.khronos.org/registry/webgl/extensions/KHR_parallel_shader_compile/ KHR_parallel_shader_compile] extension..<br />
 		- [page:String precision]: 渲染器当前使用的着色器的精度<br />
 		- [page:Boolean vertexTextures]: 如果[property:Integer maxVertexTextures]大于0，此值为*true* (即可以使用顶点纹理)<br />
 		</p>

src/materials/Material.js

@@ -68,6 +68,7 @@ function Material() {
 	this.alphaTest = 0;
 	this.premultipliedAlpha = false;
 
+	this.parallelCompile = Material.DefaultParallelCompile;
 	this.visible = true;
 
 	this.toneMapped = true;
@@ -78,6 +79,8 @@ function Material() {
 
 }
 
+Material.DefaultParallelCompile = false;
+
 Material.prototype = Object.assign( Object.create( EventDispatcher.prototype ), {
 
 	constructor: Material,

src/renderers/WebGLRenderer.js

@@ -717,6 +717,8 @@ function WebGLRenderer( parameters ) {
 
 		var program = setProgram( camera, fog, material, object );
 
+		if ( ! program.ready ) return;
+
 		var updateBuffers = false;
 
 		if ( _currentGeometryProgram.geometry !== geometry.id ||
@@ -1059,13 +1061,13 @@ function WebGLRenderer( parameters ) {
 
 					for ( var i = 0; i < object.material.length; i ++ ) {
 
-						initMaterial( object.material[ i ], scene.fog, object );
+						initMaterial( object.material[ i ], scene.fog, object, true );
 
 					}
 
 				} else {
 
-					initMaterial( object.material, scene.fog, object );
+					initMaterial( object.material, scene.fog, object, true );
 
 				}
 
@@ -1468,6 +1470,8 @@ function WebGLRenderer( parameters ) {
 
 			var program = setProgram( camera, scene.fog, material, object );
 
+			if ( ! program.ready ) return;
+
 			_currentGeometryProgram.geometry = null;
 			_currentGeometryProgram.program = null;
 			_currentGeometryProgram.wireframe = false;
@@ -1485,7 +1489,7 @@ function WebGLRenderer( parameters ) {
 
 	}
 
-	function initMaterial( material, fog, object ) {
+	function initMaterial( material, fog, object, sync ) {
 
 		var materialProperties = properties.get( material );
 
@@ -1512,13 +1516,13 @@ function WebGLRenderer( parameters ) {
 			// changed glsl or parameters
 			releaseMaterialProgramReference( material );
 
-		} else if ( materialProperties.lightsStateVersion !== lightsStateVersion ) {
+		} else if ( program.ready && materialProperties.lightsStateVersion !== lightsStateVersion ) {
 
 			materialProperties.lightsStateVersion = lightsStateVersion;
 
 			programChange = false;
 
-		} else if ( parameters.shaderID !== undefined ) {
+		} else if ( program.ready && parameters.shaderID !== undefined ) {
 
 			// same glsl and uniform list
 			return;
@@ -1566,6 +1570,15 @@ function WebGLRenderer( parameters ) {
 
 		}
 
+		if ( ! program.ready && ! program.isLinked( _this, material, sync ) ) {
+
+			materialProperties.retry = true;
+			return;
+
+		}
+
+		materialProperties.retry = false;
+
 		var programAttributes = program.getAttributes();
 
 		if ( material.morphTargets ) {
@@ -1699,9 +1712,9 @@ function WebGLRenderer( parameters ) {
 
 		}
 
-		if ( material.needsUpdate ) {
+		if ( material.needsUpdate || materialProperties.retry ) {
 
-			initMaterial( material, fog, object );
+			initMaterial( material, fog, object, false );
 			material.needsUpdate = false;
 
 		}
@@ -1710,8 +1723,11 @@ function WebGLRenderer( parameters ) {
 		var refreshMaterial = false;
 		var refreshLights = false;
 
-		var program = materialProperties.program,
-			p_uniforms = program.getUniforms(),
+		var program = materialProperties.program;
+
+		if ( ! program.ready ) return false;
+
+		var	p_uniforms = program.getUniforms(),
 			m_uniforms = materialProperties.shader.uniforms;
 
 		if ( state.useProgram( program.program ) ) {

src/renderers/webgl/WebGLCapabilities.js

@@ -85,6 +85,7 @@ function WebGLCapabilities( gl, extensions, parameters ) {
 	var floatVertexTextures = vertexTextures && floatFragmentTextures;
 
 	var maxSamples = isWebGL2 ? gl.getParameter( gl.MAX_SAMPLES ) : 0;
+	var parallelShaderCompile = extensions.get( 'KHR_parallel_shader_compile' );
 
 	return {
 
@@ -110,7 +111,9 @@ function WebGLCapabilities( gl, extensions, parameters ) {
 		floatFragmentTextures: floatFragmentTextures,
 		floatVertexTextures: floatVertexTextures,
 
-		maxSamples: maxSamples
+		maxSamples: maxSamples,
+
+		parallelShaderCompile: parallelShaderCompile
 
 	};