WebGLCapabilities: add textureTypeReadable() and textureFormatReadable() (#28087)

src/renderers/WebGLRenderer.js

@@ -3,9 +3,7 @@ import {
 	BackSide,
 	FrontSide,
 	DoubleSide,
-	RGBAFormat,
 	HalfFloatType,
-	FloatType,
 	UnsignedByteType,
 	NoToneMapping,
 	LinearMipmapLinearFilter,
@@ -292,10 +290,10 @@ class WebGLRenderer {
 			extensions = new WebGLExtensions( _gl );
 			extensions.init();
 
-			capabilities = new WebGLCapabilities( _gl, extensions, parameters );
-
 			utils = new WebGLUtils( _gl, extensions );
 
+			capabilities = new WebGLCapabilities( _gl, extensions, parameters, utils );
+
 			state = new WebGLState( _gl );
 
 			info = new WebGLInfo( _gl );
@@ -2288,17 +2286,14 @@ class WebGLRenderer {
 					const textureFormat = texture.format;
 					const textureType = texture.type;
 
-					if ( textureFormat !== RGBAFormat && utils.convert( textureFormat ) !== _gl.getParameter( _gl.IMPLEMENTATION_COLOR_READ_FORMAT ) ) {
+					if ( ! capabilities.textureFormatReadable( textureFormat ) ) {
 
 						console.error( 'THREE.WebGLRenderer.readRenderTargetPixels: renderTarget is not in RGBA or implementation defined format.' );
 						return;
 
 					}
 
-					const halfFloatSupportedByExt = ( textureType === HalfFloatType ) && ( extensions.has( 'EXT_color_buffer_half_float' ) || extensions.has( 'EXT_color_buffer_float' ) );
-
-					if ( textureType !== UnsignedByteType && utils.convert( textureType ) !== _gl.getParameter( _gl.IMPLEMENTATION_COLOR_READ_TYPE ) && // Edge and Chrome Mac < 52 (#9513)
-						textureType !== FloatType && ! halfFloatSupportedByExt ) {
+					if ( ! capabilities.textureTypeReadable( textureType ) ) {
 
 						console.error( 'THREE.WebGLRenderer.readRenderTargetPixels: renderTarget is not in UnsignedByteType or implementation defined type.' );
 						return;

src/renderers/webgl/WebGLCapabilities.js

@@ -1,4 +1,6 @@
-function WebGLCapabilities( gl, extensions, parameters ) {
+import { FloatType, HalfFloatType, RGBAFormat, UnsignedByteType } from '../../constants.js';
+
+function WebGLCapabilities( gl, extensions, parameters, utils ) {
 
 	let maxAnisotropy;
 
@@ -22,6 +24,33 @@ function WebGLCapabilities( gl, extensions, parameters ) {
 
 	}
 
+	function textureFormatReadable( textureFormat ) {
+
+		if ( textureFormat !== RGBAFormat && utils.convert( textureFormat ) !== gl.getParameter( gl.IMPLEMENTATION_COLOR_READ_FORMAT ) ) {
+
+			return false;
+
+		}
+
+		return true;
+
+	}
+
+	function textureTypeReadable( textureType ) {
+
+		const halfFloatSupportedByExt = ( textureType === HalfFloatType ) && ( extensions.has( 'EXT_color_buffer_half_float' ) || extensions.has( 'EXT_color_buffer_float' ) );
+
+		if ( textureType !== UnsignedByteType && utils.convert( textureType ) !== gl.getParameter( gl.IMPLEMENTATION_COLOR_READ_TYPE ) && // Edge and Chrome Mac < 52 (#9513)
+			textureType !== FloatType && ! halfFloatSupportedByExt ) {
+
+			return false;
+
+		}
+
+		return true;
+
+	}
+
 	function getMaxPrecision( precision ) {
 
 		if ( precision === 'highp' ) {
@@ -85,6 +114,9 @@ function WebGLCapabilities( gl, extensions, parameters ) {
 		getMaxAnisotropy: getMaxAnisotropy,
 		getMaxPrecision: getMaxPrecision,
 
+		textureFormatReadable: textureFormatReadable,
+		textureTypeReadable: textureTypeReadable,
+
 		precision: precision,
 		logarithmicDepthBuffer: logarithmicDepthBuffer,