Adding a position options for the PMREM fromScene generation

[Samsy]

Description

Currently, calling a PMREM Generation is calling a cubecamera that is always default positionned at 0, 0, 0

For a few versions now, I'm hacking my way to get to generate a PMREM but from an arbitrary cubecamera position by passing a position to pmrem.fromScene, this would be useful

Solution

Passing a position as arg to fromScene

Alternatives

Or maybe passing a callback to be called before each render that passes the camera ?
in that case we'd be able to do anything before render of each pmrem face

Additional context

No response

[Spiri0]

@Mugen87 can you still remember it? #28334
I tried to solve that back then. This was probably one of my first attempts to understand something in threejs.
But I still had a mistake there. With the extension I tried to make size and position optional and to fix the reflection error that Sunag recently fixed with a PR #30063 because that also came up recently. Maybe my approach from back then can be useful