getDepthBuffer(    renderer: WebGLRenderer,    scene: Scene,    camera: Camera,    width: number,    height: number,): Promise<null | Float32Array<ArrayBufferLike>> Parameters
- renderer: WebGLRenderer
 - scene: Scene
 - camera: Camera
 - width: number
 - height: number
 
Returns Promise<null | Float32Array<ArrayBufferLike>>
Generate a depth buffer and read-back values as normalized device coordinates (ndc) for objects assigned to the occluder layer