Extension of the WebGPU copyTextureToTexture function for array textures (#29364)

* Extension of the copyTextureToTexture function to also be able to use array textures

* Update WebGPUBackend.js

remove empty space

src/renderers/webgpu/WebGPUBackend.js

@@ -1365,9 +1365,11 @@ class WebGPUBackend extends Backend {
 
 		let dstX = 0;
 		let dstY = 0;
+		let dstLayer = 0;
 
 		let srcX = 0;
 		let srcY = 0;
+		let srcLayer = 0;
 
 		let srcWidth = srcTexture.image.width;
 		let srcHeight = srcTexture.image.height;
@@ -1376,6 +1378,7 @@ class WebGPUBackend extends Backend {
 
 			srcX = srcRegion.x;
 			srcY = srcRegion.y;
+			srcLayer = srcRegion.z || 0;
 			srcWidth = srcRegion.width;
 			srcHeight = srcRegion.height;
 
@@ -1385,6 +1388,7 @@ class WebGPUBackend extends Backend {
 
 			dstX = dstPosition.x;
 			dstY = dstPosition.y;
+			dstLayer = dstPosition.z || 0;
 
 		}
 
@@ -1397,16 +1401,17 @@ class WebGPUBackend extends Backend {
 			{
 				texture: sourceGPU,
 				mipLevel: level,
-				origin: { x: srcX, y: srcY, z: 0 }
+				origin: { x: srcX, y: srcY, z: srcLayer }
 			},
 			{
 				texture: destinationGPU,
 				mipLevel: level,
-				origin: { x: dstX, y: dstY, z: 0 }
+				origin: { x: dstX, y: dstY, z: dstLayer }
 			},
 			[
 				srcWidth,
-				srcHeight
+				srcHeight,
+				1
 			]
 		);