Revert "Add support for the EXT_multisampled_render_to_texture extension and use it for WebXR (#22550)" (#22625)

This reverts commit c789b20ee6ba1cf41fad7ba52e1564fc4bf78cb6.

src/renderers/webgl/WebGLExtensions.js

@@ -70,7 +70,6 @@ function WebGLExtensions( gl ) {
 
 			getExtension( 'OES_texture_float_linear' );
 			getExtension( 'EXT_color_buffer_half_float' );
-			getExtension( 'EXT_multisampled_render_to_texture' );
 
 		},
 

src/renderers/webxr/WebXRManager.js

@@ -33,8 +33,6 @@ class WebXRManager extends EventDispatcher {
 		let xrFrame = null;
 		let depthStyle = null;
 		let clearStyle = null;
-		const msaartcSupported = renderer.extensions.has( 'EXT_multisampled_render_to_texture' );
-		let msaaExt = null;
 
 		const controllers = [];
 		const inputSourcesMap = new Map();
@@ -304,11 +302,7 @@ class WebXRManager extends EventDispatcher {
 
 					session.updateRenderState( { layers: [ glProjLayer ] } );
 
-					if ( isMultisample && msaartcSupported ) {
-
-						msaaExt = renderer.extensions.get( 'EXT_multisampled_render_to_texture' );
-
-					} else if ( isMultisample ) {
+					if ( isMultisample ) {
 
 						glMultisampledFramebuffer = gl.createFramebuffer();
 						glColorRenderbuffer = gl.createRenderbuffer();
@@ -629,28 +623,14 @@ class WebXRManager extends EventDispatcher {
 
 						state.bindXRFramebuffer( glFramebuffer );
 
-						if ( isMultisample && msaartcSupported ) {
-
-							if ( glSubImage.depthStencilTexture !== undefined ) {
-
-								msaaExt.framebufferTexture2DMultisampleEXT( gl.FRAMEBUFFER, depthStyle, gl.TEXTURE_2D, glSubImage.depthStencilTexture, 0, 4 );
-
-							}
-
-							msaaExt.framebufferTexture2DMultisampleEXT( gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, glSubImage.colorTexture, 0, 4 );
+						if ( glSubImage.depthStencilTexture !== undefined ) {
 
-						} else {
-
-							if ( glSubImage.depthStencilTexture !== undefined ) {
-
-								gl.framebufferTexture2D( gl.FRAMEBUFFER, depthStyle, gl.TEXTURE_2D, glSubImage.depthStencilTexture, 0 );
-
-							}
-
-							gl.framebufferTexture2D( gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, glSubImage.colorTexture, 0 );
+							gl.framebufferTexture2D( gl.FRAMEBUFFER, depthStyle, gl.TEXTURE_2D, glSubImage.depthStencilTexture, 0 );
 
 						}
 
+						gl.framebufferTexture2D( gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, glSubImage.colorTexture, 0 );
+
 						viewport = glSubImage.viewport;
 
 					}
@@ -675,7 +655,7 @@ class WebXRManager extends EventDispatcher {
 
 				}
 
-				if ( isMultisample && ! msaartcSupported ) {
+				if ( isMultisample ) {
 
 					state.bindXRFramebuffer( glMultisampledFramebuffer );
 
@@ -700,7 +680,7 @@ class WebXRManager extends EventDispatcher {
 
 			if ( onAnimationFrameCallback ) onAnimationFrameCallback( time, frame );
 
-			if ( isMultisample && ! msaartcSupported ) {
+			if ( isMultisample ) {
 
 				const width = glProjLayer.textureWidth;
 				const height = glProjLayer.textureHeight;