[Solved] How can I render a shader to a render target?

OK, but your code is missing the step where rendering is started without one, and a render target is assigned.

If the “cameraOrtho” from the Three.js instructions bellow could be eliminated by increasing efficiency without increasing complexity too much, then it could be a great alternative.

renderer.setRenderTarget(AATex);
renderer.render(sceneRT2TB, cameraOrtho);