WebGLRenderer: Fix binding __webglFramebuffer when mipmaps are used. (#30746)

* Fix binding __webglFramebuffer when mipmaps are used

Closes #30745

* Handle crash when msaa sample used

* Correct formatting

* Consistency

Author: haxiomic

src/renderers/webgl/WebGLTextures.js

@@ -1629,7 +1629,17 @@ function WebGLTextures( _gl, extensions, state, properties, capabilities, utils,
 
 			if ( isCube ) throw new Error( 'target.depthTexture not supported in Cube render targets' );
 
-			setupDepthTexture( renderTargetProperties.__webglFramebuffer, renderTarget );
+			const mipmaps = renderTarget.texture.mipmaps;
+
+			if ( mipmaps && mipmaps.length > 0 ) {
+
+				setupDepthTexture( renderTargetProperties.__webglFramebuffer[ 0 ], renderTarget );
+
+			} else {
+
+				setupDepthTexture( renderTargetProperties.__webglFramebuffer, renderTarget );
+
+			}
 
 		} else {
 
@@ -1660,7 +1670,17 @@ function WebGLTextures( _gl, extensions, state, properties, capabilities, utils,
 
 			} else {
 
-				state.bindFramebuffer( _gl.FRAMEBUFFER, renderTargetProperties.__webglFramebuffer );
+				const mipmaps = renderTarget.texture.mipmaps;
+
+				if ( mipmaps && mipmaps.length > 0 ) {
+
+					state.bindFramebuffer( _gl.FRAMEBUFFER, renderTargetProperties.__webglFramebuffer[ 0 ] );
+
+				} else {
+
+					state.bindFramebuffer( _gl.FRAMEBUFFER, renderTargetProperties.__webglFramebuffer );
+
+				}
 
 				if ( renderTargetProperties.__webglDepthbuffer === undefined ) {
 
@@ -1990,7 +2010,18 @@ function WebGLTextures( _gl, extensions, state, properties, capabilities, utils,
 				}
 
 				state.bindFramebuffer( _gl.READ_FRAMEBUFFER, renderTargetProperties.__webglMultisampledFramebuffer );
-				state.bindFramebuffer( _gl.DRAW_FRAMEBUFFER, renderTargetProperties.__webglFramebuffer );
+
+				const mipmaps = renderTarget.texture.mipmaps;
+
+				if ( mipmaps && mipmaps.length > 0 ) {
+
+					state.bindFramebuffer( _gl.DRAW_FRAMEBUFFER, renderTargetProperties.__webglFramebuffer[ 0 ] );
+
+				} else {
+
+					state.bindFramebuffer( _gl.DRAW_FRAMEBUFFER, renderTargetProperties.__webglFramebuffer );
+
+				}
 
 				for ( let i = 0; i < textures.length; i ++ ) {