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AR: Modifying / Changing PrecomputedLightVolume values for character lighting

For displaying dynamic objects in an AR app, we would like to be able to change the lighting on the characters to match target lighting.

Dominant light is dynamic directional. That is obviously easy to adjust.
We can capture cubemaps for all the environment maps we want to use for secondary lighting. However, the current unreal pipeline for this is:

  1. Apply the cubemap as a skylight
  2. Set up lightmass importance volume
  3. Bake lighting
  4. Have a second dynamic directional light for direct lighting and shadowcasting.

This takes a long time and we have to do it in editor.
Since our objects are dynamic, we don’t really need the bake but this generates the precomputed light volumes.

In principal, my scene could have a precomputed light volume with only one light radiance point. So to change the lighting, I would just need to change the SH vectors on that one sample. I wouldn’t even mind iterating through all the points and changing them to the same.

Anyone try anything along this road before I head down it myself?