- Create a scene with animated dynamic lights
- Bake out this animation into a per-frame lightmap for the entire scene. Essentially there's a high-res 2-8K texture encoding lighting for the entire scene, for each frame
- Assemble these lightmap frames into a video file
- Load the geoemtry of these scene from step 1 into a game engine, together with the video from the previous step
- Apply the texture of the film to the geometry and play the video
Ideally the texturing of the geometry consist of two texture channels, albedo and the pre-baked per-frame lightmap.
Does Houdini have tools that could aid in generating this per-frame lightmap of the entire scene? Unfortunately I don't have the budget to do a lot of technical implementation work myself.