I'm looking to take a 2D texture (previously rendered from the user's perspective), and overlay it overtop of a cubemap.
Since a cubemap has 6 textures, I need to run a shader over top of all 6, and use some formula for calculating the UV from a given view.
I'm at a loss for how to calculate this.
If the user were to spin around in 1 spot, they would build up full panoramic cubemap.
The intention is to reuse end-of-frame data to update a persistent cubemap that follows the user.
I know how to build manual cubemaps by rendering a scene 6 times, once on all axes, however in this case I wish to take an already rendered view and transplant it onto the correct spots on a cubemap.