WebGPURenderer: Only use HalfFloatType for the framebuffer target if necessary.

examples/webgpu_lights_custom.html

@@ -113,6 +113,7 @@
 				renderer.setPixelRatio( window.devicePixelRatio );
 				renderer.setSize( window.innerWidth, window.innerHeight );
 				renderer.setAnimationLoop( animate );
+				renderer.toneMapping = THREE.LinearToneMapping;
 				document.body.appendChild( renderer.domElement );
 
 				// controls

src/renderers/common/Backend.js

@@ -4,7 +4,7 @@ let _color4 = null;
 import Color4 from './Color4.js';
 import { Vector2 } from '../../math/Vector2.js';
 import { createCanvasElement, warnOnce } from '../../utils.js';
-import { REVISION } from '../../constants.js';
+import { HalfFloatType, REVISION } from '../../constants.js';
 
 /**
  * Most of the rendering related logic is implemented in the
@@ -588,6 +588,17 @@ class Backend {
 
 	}
 
+	/**
+	 * Returns `true` if the backend requires a framebuffer target with type `HalfFloat`.
+	 *
+	 * @return {Boolean} Whether the backend requires a framebuffer target with type `HalfFloat` or not.
+	 */
+	needsHalfFloatFrameBufferTarget() {
+
+		return ( this.parameters.outputType === HalfFloatType );
+
+	}
+
 	/**
 	 * Sets a dictionary for the given object into the
 	 * internal data structure.

src/renderers/common/Renderer.js

@@ -26,7 +26,7 @@ import { Matrix4 } from '../../math/Matrix4.js';
 import { Vector2 } from '../../math/Vector2.js';
 import { Vector4 } from '../../math/Vector4.js';
 import { RenderTarget } from '../../core/RenderTarget.js';
-import { DoubleSide, BackSide, FrontSide, SRGBColorSpace, NoToneMapping, LinearFilter, LinearSRGBColorSpace, HalfFloatType, RGBAFormat, PCFShadowMap } from '../../constants.js';
+import { DoubleSide, BackSide, FrontSide, SRGBColorSpace, NoToneMapping, LinearFilter, LinearSRGBColorSpace, HalfFloatType, RGBAFormat, PCFShadowMap, UnsignedByteType } from '../../constants.js';
 
 /** @module Renderer **/
 
@@ -445,13 +445,13 @@ class Renderer {
 		this._transparentSort = null;
 
 		/**
-		 * The framebuffer target.
+		 * A map that holds a framebuffer target for each render
+		 * target type.
 		 *
 		 * @private
-		 * @type {RenderTarget?}
-		 * @default null
+		 * @type {Map<Number,RenderTarget>}
 		 */
-		this._frameBufferTarget = null;
+		this._frameBufferTargetMap = new Map();
 
 		const alphaClear = this.alpha === true ? 0 : 1;
 
@@ -1121,14 +1121,19 @@ class Renderer {
 		const { width, height } = this.getDrawingBufferSize( _drawingBufferSize );
 		const { depth, stencil } = this;
 
-		let frameBufferTarget = this._frameBufferTarget;
+		// to improve performance we only want to use HalfFloatType if necessary
+		// HalfFloatType is required when a) tone mapping is used or b) the backend specifically requests it
+
+		const type = ( useToneMapping || this.backend.needsHalfFloatFrameBufferTarget() ) ? HalfFloatType : UnsignedByteType;
 
-		if ( frameBufferTarget === null ) {
+		let frameBufferTarget = this._frameBufferTargetMap.get( type );
+
+		if ( frameBufferTarget === undefined ) {
 
 			frameBufferTarget = new RenderTarget( width, height, {
 				depthBuffer: depth,
 				stencilBuffer: stencil,
-				type: HalfFloatType, // FloatType
+				type: type,
 				format: RGBAFormat,
 				colorSpace: LinearSRGBColorSpace,
 				generateMipmaps: false,
@@ -1139,7 +1144,7 @@ class Renderer {
 
 			frameBufferTarget.isPostProcessingRenderTarget = true;
 
-			this._frameBufferTarget = frameBufferTarget;
+			this._frameBufferTargetMap.set( type, frameBufferTarget );
 
 		}
 
@@ -2026,6 +2031,14 @@ class Renderer {
 		this._renderContexts.dispose();
 		this._textures.dispose();
 
+		for ( const renderTarget of this._frameBufferTargetMap.values() ) {
+
+			renderTarget.dispose();
+
+		}
+
+		this._frameBufferTargetMap.clear();
+
 		Object.values( this.backend.timestampQueryPool ).forEach( queryPool => {
 
 			if ( queryPool !== null ) queryPool.dispose();