Renderer: Remove `waitForGPU()`. (#32024)

src/renderers/common/Backend.js

@@ -575,16 +575,6 @@ class Backend {
 
 	}
 
-	/**
-	 * Can be used to synchronize CPU operations with GPU tasks. So when this method is called,
-	 * the CPU waits for the GPU to complete its operation (e.g. a compute task).
-	 *
-	 * @async
-	 * @abstract
-	 * @return {Promise} A Promise that resolves when synchronization has been finished.
-	 */
-	async waitForGPU() {}
-
 	/**
 	 * This method performs a readback operation by moving buffer data from
 	 * a storage buffer attribute from the GPU to the CPU.

src/renderers/common/Renderer.js

@@ -983,11 +983,12 @@ class Renderer {
 	 * the CPU waits for the GPU to complete its operation (e.g. a compute task).
 	 *
 	 * @async
+	 * @deprecated
 	 * @return {Promise} A Promise that resolves when synchronization has been finished.
 	 */
 	async waitForGPU() {
 
-		await this.backend.waitForGPU();
+		error( 'Renderer: waitForGPU() has been removed. Read https://github.com/mrdoob/three.js/issues/32012 for more information.' );
 
 	}
 

src/renderers/webgl-fallback/WebGLBackend.js

@@ -297,19 +297,6 @@ class WebGLBackend extends Backend {
 
 	}
 
-	/**
-	 * Can be used to synchronize CPU operations with GPU tasks. So when this method is called,
-	 * the CPU waits for the GPU to complete its operation (e.g. a compute task).
-	 *
-	 * @async
-	 * @return {Promise} A Promise that resolves when synchronization has been finished.
-	 */
-	async waitForGPU() {
-
-		await this.utils._clientWaitAsync();
-
-	}
-
 	/**
 	 * Ensures the backend is XR compatible.
 	 *

src/renderers/webgpu/WebGPUBackend.js

@@ -1435,19 +1435,6 @@ class WebGPUBackend extends Backend {
 
 	}
 
-	/**
-	 * Can be used to synchronize CPU operations with GPU tasks. So when this method is called,
-	 * the CPU waits for the GPU to complete its operation (e.g. a compute task).
-	 *
-	 * @async
-	 * @return {Promise} A Promise that resolves when synchronization has been finished.
-	 */
-	async waitForGPU() {
-
-		await this.device.queue.onSubmittedWorkDone();
-
-	}
-
 	// render object
 
 	/**