WebGLRenderer: Fix transmission with nested render calls. (#27886)

* WebGLRenderer: Fix transmission with nested render calls.

* Update screenshot.

examples/webxr_vr_sandbox.html

@@ -102,15 +102,14 @@
 				//
 
 				reflector = new Reflector( new THREE.PlaneGeometry( 2, 2 ), {
-					textureWidth: window.innerWidth * window.devicePixelRatio,
-					textureHeight: window.innerHeight * window.devicePixelRatio
+					textureWidth: window.innerWidth,
+					textureHeight: window.innerHeight
 				} );
 				reflector.position.x = 1;
 				reflector.position.y = 1.5;
 				reflector.position.z = - 3;
 				reflector.rotation.y = - Math.PI / 4;
-				// TOFIX: Reflector breaks transmission
-				// scene.add( reflector );
+				scene.add( reflector );
 
 				const frameGeometry = new THREE.BoxGeometry( 2.1, 2.1, 0.1 );
 				const frameMaterial = new THREE.MeshPhongMaterial();

src/renderers/WebGLRenderer.js

@@ -201,10 +201,6 @@ class WebGLRenderer {
 		let _clippingEnabled = false;
 		let _localClippingEnabled = false;
 
-		// transmission
-
-		let _transmissionRenderTarget = null;
-
 		// camera matrices cache
 
 		const _projScreenMatrix = new Matrix4();
@@ -654,13 +650,6 @@ class WebGLRenderer {
 			xr.removeEventListener( 'sessionstart', onXRSessionStart );
 			xr.removeEventListener( 'sessionend', onXRSessionEnd );
 
-			if ( _transmissionRenderTarget ) {
-
-				_transmissionRenderTarget.dispose();
-				_transmissionRenderTarget = null;
-
-			}
-
 			animation.stop();
 
 		};
@@ -1412,9 +1401,9 @@ class WebGLRenderer {
 
 			}
 
-			if ( _transmissionRenderTarget === null ) {
+			if ( currentRenderState.state.transmissionRenderTarget === null ) {
 
-				_transmissionRenderTarget = new WebGLRenderTarget( 1, 1, {
+				currentRenderState.state.transmissionRenderTarget = new WebGLRenderTarget( 1, 1, {
 					generateMipmaps: true,
 					type: ( extensions.has( 'EXT_color_buffer_half_float' ) || extensions.has( 'EXT_color_buffer_float' ) ) ? HalfFloatType : UnsignedByteType,
 					minFilter: LinearMipmapLinearFilter,
@@ -1433,13 +1422,15 @@ class WebGLRenderer {
 
 			}
 
+			const transmissionRenderTarget = currentRenderState.state.transmissionRenderTarget;
+
 			_this.getDrawingBufferSize( _vector2 );
-			_transmissionRenderTarget.setSize( _vector2.x, _vector2.y );
+			transmissionRenderTarget.setSize( _vector2.x, _vector2.y );
 
 			//
 
 			const currentRenderTarget = _this.getRenderTarget();
-			_this.setRenderTarget( _transmissionRenderTarget );
+			_this.setRenderTarget( transmissionRenderTarget );
 
 			_this.getClearColor( _currentClearColor );
 			_currentClearAlpha = _this.getClearAlpha();
@@ -1454,8 +1445,8 @@ class WebGLRenderer {
 
 			renderObjects( opaqueObjects, scene, camera );
 
-			textures.updateMultisampleRenderTarget( _transmissionRenderTarget );
-			textures.updateRenderTargetMipmap( _transmissionRenderTarget );
+			textures.updateMultisampleRenderTarget( transmissionRenderTarget );
+			textures.updateRenderTargetMipmap( transmissionRenderTarget );
 
 			let renderTargetNeedsUpdate = false;
 
@@ -1488,8 +1479,8 @@ class WebGLRenderer {
 
 			if ( renderTargetNeedsUpdate === true ) {
 
-				textures.updateMultisampleRenderTarget( _transmissionRenderTarget );
-				textures.updateRenderTargetMipmap( _transmissionRenderTarget );
+				textures.updateMultisampleRenderTarget( transmissionRenderTarget );
+				textures.updateRenderTargetMipmap( transmissionRenderTarget );
 
 			}
 
@@ -2022,7 +2013,7 @@ class WebGLRenderer {
 
 				}
 
-				materials.refreshMaterialUniforms( m_uniforms, material, _pixelRatio, _height, _transmissionRenderTarget );
+				materials.refreshMaterialUniforms( m_uniforms, material, _pixelRatio, _height, currentRenderState.state.transmissionRenderTarget );
 
 				WebGLUniforms.upload( _gl, getUniformList( materialProperties ), m_uniforms, textures );
 

src/renderers/webgl/WebGLRenderStates.js

@@ -42,7 +42,9 @@ function WebGLRenderState( extensions ) {
 		lightsArray: lightsArray,
 		shadowsArray: shadowsArray,
 
-		lights: lights
+		lights: lights,
+
+		transmissionRenderTarget: null
 	};
 
 	return {