WebXRManager: synchronize sizing with renderer (#26905)

* WebXRManager: synchronize sizing with renderer

* Update WebXRManager.js

* Update WebXRManager.js

src/renderers/webxr/WebXRManager.js

@@ -1,6 +1,7 @@
 import { ArrayCamera } from '../../cameras/ArrayCamera.js';
 import { EventDispatcher } from '../../core/EventDispatcher.js';
 import { PerspectiveCamera } from '../../cameras/PerspectiveCamera.js';
+import { Vector2 } from '../../math/Vector2.js';
 import { Vector3 } from '../../math/Vector3.js';
 import { Vector4 } from '../../math/Vector4.js';
 import { RAD2DEG } from '../../math/MathUtils.js';
@@ -40,6 +41,9 @@ class WebXRManager extends EventDispatcher {
 		const controllers = [];
 		const controllerInputSources = [];
 
+		const currentSize = new Vector2();
+		let currentPixelRatio = null;
+
 		//
 
 		const cameraL = new PerspectiveCamera();
@@ -176,6 +180,9 @@ class WebXRManager extends EventDispatcher {
 
 			scope.isPresenting = false;
 
+			renderer.setPixelRatio( currentPixelRatio );
+			renderer.setSize( currentSize.width, currentSize.height, false );
+
 			scope.dispatchEvent( { type: 'sessionend' } );
 
 		}
@@ -263,6 +270,9 @@ class WebXRManager extends EventDispatcher {
 
 				}
 
+				currentPixelRatio = renderer.getPixelRatio();
+				renderer.getSize( currentSize );
+
 				if ( ( session.renderState.layers === undefined ) || ( renderer.capabilities.isWebGL2 === false ) ) {
 
 					const layerInit = {
@@ -277,6 +287,9 @@ class WebXRManager extends EventDispatcher {
 
 					session.updateRenderState( { baseLayer: glBaseLayer } );
 
+					renderer.setPixelRatio( 1 );
+					renderer.setSize( glBaseLayer.framebufferWidth, glBaseLayer.framebufferHeight, false );
+
 					newRenderTarget = new WebGLRenderTarget(
 						glBaseLayer.framebufferWidth,
 						glBaseLayer.framebufferHeight,
@@ -314,6 +327,9 @@ class WebXRManager extends EventDispatcher {
 
 					session.updateRenderState( { layers: [ glProjLayer ] } );
 
+					renderer.setPixelRatio( 1 );
+					renderer.setSize( glProjLayer.textureWidth, glProjLayer.textureHeight, false );
+
 					newRenderTarget = new WebGLRenderTarget(
 						glProjLayer.textureWidth,
 						glProjLayer.textureHeight,