WebGPURenderer: Reduce memory churn when using chain maps.

src/renderers/common/Lighting.js

@@ -2,6 +2,7 @@ import { LightsNode } from '../../nodes/Nodes.js';
 import ChainMap from './ChainMap.js';
 
 const _defaultLights = /*@__PURE__*/ new LightsNode();
+const _chainKeys = [];
 
 /**
  * This renderer module manages the lights nodes which are unique
@@ -49,19 +50,20 @@ class Lighting extends ChainMap {
 
 		if ( scene.isQuadMesh ) return _defaultLights;
 
-		// tiled lighting
+		_chainKeys[ 0 ] = scene;
+		_chainKeys[ 1 ] = camera;
 
-		const keys = [ scene, camera ];
-
-		let node = this.get( keys );
+		let node = this.get( _chainKeys );
 
 		if ( node === undefined ) {
 
 			node = this.createNode();
-			this.set( keys, node );
+			this.set( _chainKeys, node );
 
 		}
 
+		_chainKeys.length = 0;
+
 		return node;
 
 	}

src/renderers/common/RenderBundles.js

@@ -1,6 +1,8 @@
 import ChainMap from './ChainMap.js';
 import RenderBundle from './RenderBundle.js';
 
+const _chainKeys = [];
+
 /**
  * This renderer module manages render bundles.
  *
@@ -32,17 +34,21 @@ class RenderBundles {
 	get( bundleGroup, camera ) {
 
 		const bundles = this.bundles;
-		const keys = [ bundleGroup, camera ];
 
-		let bundle = bundles.get( keys );
+		_chainKeys[ 0 ] = bundleGroup;
+		_chainKeys[ 1 ] = camera;
+
+		let bundle = bundles.get( _chainKeys );
 
 		if ( bundle === undefined ) {
 
 			bundle = new RenderBundle( bundleGroup, camera );
-			bundles.set( keys, bundle );
+			bundles.set( _chainKeys, bundle );
 
 		}
 
+		_chainKeys.length = 0;
+
 		return bundle;
 
 	}

src/renderers/common/RenderContexts.js

@@ -1,6 +1,8 @@
 import ChainMap from './ChainMap.js';
 import RenderContext from './RenderContext.js';
 
+const _chainKeys = [];
+
 /**
  * This module manages the render contexts of the renderer.
  *
@@ -33,13 +35,12 @@ class RenderContexts {
 	 */
 	get( scene = null, camera = null, renderTarget = null ) {
 
-		const chainKey = [];
-		if ( scene !== null ) chainKey.push( scene );
-		if ( camera !== null ) chainKey.push( camera );
+		if ( scene !== null ) _chainKeys.push( scene );
+		if ( camera !== null ) _chainKeys.push( camera );
 
-		if ( chainKey.length === 0 ) {
+		if ( _chainKeys.length === 0 ) {
 
-			chainKey.push( { id: 'default' } );
+			_chainKeys.push( { id: 'default' } );
 
 		}
 
@@ -61,16 +62,18 @@ class RenderContexts {
 
 		const chainMap = this.getChainMap( attachmentState );
 
-		let renderState = chainMap.get( chainKey );
+		let renderState = chainMap.get( _chainKeys );
 
 		if ( renderState === undefined ) {
 
 			renderState = new RenderContext();
 
-			chainMap.set( chainKey, renderState );
+			chainMap.set( _chainKeys, renderState );
 
 		}
 
+		_chainKeys.length = 0;
+
 		if ( renderTarget !== null ) renderState.sampleCount = renderTarget.samples === 0 ? 1 : renderTarget.samples;
 
 		return renderState;

src/renderers/common/RenderLists.js

@@ -1,6 +1,8 @@
 import ChainMap from './ChainMap.js';
 import RenderList from './RenderList.js';
 
+const _chainKeys = [];
+
 /**
  * This renderer module manages the render lists which are unique
  * per scene and camera combination.
@@ -42,17 +44,21 @@ class RenderLists {
 	get( scene, camera ) {
 
 		const lists = this.lists;
-		const keys = [ scene, camera ];
 
-		let list = lists.get( keys );
+		_chainKeys[ 0 ] = scene;
+		_chainKeys[ 1 ] = camera;
+
+		let list = lists.get( _chainKeys );
 
 		if ( list === undefined ) {
 
 			list = new RenderList( this.lighting, scene, camera );
-			lists.set( keys, list );
+			lists.set( _chainKeys, list );
 
 		}
 
+		_chainKeys.length = 0;
+
 		return list;
 
 	}

src/renderers/common/RenderObjects.js

@@ -1,7 +1,7 @@
 import ChainMap from './ChainMap.js';
 import RenderObject from './RenderObject.js';
 
-const _chainArray = [];
+const _chainKeys = [];
 
 /**
  * This module manages the render objects of the renderer.
@@ -92,18 +92,18 @@ class RenderObjects {
 		const chainMap = this.getChainMap( passId );
 
 		// reuse chainArray
-		_chainArray[ 0 ] = object;
-		_chainArray[ 1 ] = material;
-		_chainArray[ 2 ] = renderContext;
-		_chainArray[ 3 ] = lightsNode;
+		_chainKeys[ 0 ] = object;
+		_chainKeys[ 1 ] = material;
+		_chainKeys[ 2 ] = renderContext;
+		_chainKeys[ 3 ] = lightsNode;
 
-		let renderObject = chainMap.get( _chainArray );
+		let renderObject = chainMap.get( _chainKeys );
 
 		if ( renderObject === undefined ) {
 
 			renderObject = this.createRenderObject( this.nodes, this.geometries, this.renderer, object, material, scene, camera, lightsNode, renderContext, clippingContext, passId );
 
-			chainMap.set( _chainArray, renderObject );
+			chainMap.set( _chainKeys, renderObject );
 
 		} else {
 
@@ -133,6 +133,8 @@ class RenderObjects {
 
 		}
 
+		_chainKeys.length = 0;
+
 		return renderObject;
 
 	}

src/renderers/common/nodes/Nodes.js

@@ -9,6 +9,7 @@ import { CubeUVReflectionMapping, EquirectangularReflectionMapping, Equirectangu
 import { hashArray } from '../../../nodes/core/NodeUtils.js';
 
 const _outputNodeMap = new WeakMap();
+const _chainKeys = [];
 
 /**
  * This renderer module manages node-related objects and is the
@@ -136,10 +137,13 @@ class Nodes extends DataMap {
 
 		// other groups are updated just when groupNode.needsUpdate is true
 
-		const groupChain = [ groupNode, nodeUniformsGroup ];
+		_chainKeys[ 0 ] = groupNode;
+		_chainKeys[ 1 ] = nodeUniformsGroup;
 
-		let groupData = this.groupsData.get( groupChain );
-		if ( groupData === undefined ) this.groupsData.set( groupChain, groupData = {} );
+		let groupData = this.groupsData.get( _chainKeys );
+		if ( groupData === undefined ) this.groupsData.set( _chainKeys, groupData = {} );
+
+		_chainKeys.length = 0;
 
 		if ( groupData.version !== groupNode.version ) {
 
@@ -382,10 +386,12 @@ class Nodes extends DataMap {
 	 */
 	getCacheKey( scene, lightsNode ) {
 
-		const chain = [ scene, lightsNode ];
+		_chainKeys[ 0 ] = scene;
+		_chainKeys[ 1 ] = lightsNode;
+
 		const callId = this.renderer.info.calls;
 
-		let cacheKeyData = this.callHashCache.get( chain );
+		let cacheKeyData = this.callHashCache.get( _chainKeys );
 
 		if ( cacheKeyData === undefined || cacheKeyData.callId !== callId ) {
 
@@ -405,10 +411,12 @@ class Nodes extends DataMap {
 				cacheKey: hashArray( values )
 			};
 
-			this.callHashCache.set( chain, cacheKeyData );
+			this.callHashCache.set( _chainKeys, cacheKeyData );
 
 		}
 
+		_chainKeys.length = 0;
+
 		return cacheKeyData.cacheKey;
 
 	}