Description

Currently when calling copyTextureToTexture with two render target textures you get the following warning. I'm not sure if this is a limitation of the underlying WebGL APIs or if this is possible to achieve if we change something about the function:

WebGL: INVALID_OPERATION: texSubImage2D: no bound PIXEL_UNPACK_BUFFER

Repro code:

import * as THREE from 'three';

const renderer = new THREE.WebGLRenderer( { antialias: true } );
const r1 = new THREE.WebGLRenderTarget( 100, 100 );
const r2 = new THREE.WebGLRenderTarget( 100, 100 );

renderer.initRenderTarget( r1 );
renderer.initRenderTarget( r2 );
renderer.copyTextureToTexture( r1.texture, r2.texture );

Solution

Adjust underlying function implementation to support copying data between render target textures for 2d and 3d textures.

Alternatives

Use a custom FullScreenPass method for copying data.

Additional context

No response