Clearly a scene / engine can have more than one 3D texture. I have found a number of cases when forced to only have one environment texture for the entire scene is a major pain. The workarounds have their own problems:
- Reduce environment intensity of some materials only works in limited situations.
- Abandoning an environment texture,
environmentIntensity = 0, & using only lights for some PBR materials looks like a bunch of spots no matter which light type I tried. Also time consuming.
- Using standard materials looks out of place, and cannot be metal, rough, and poorer transparency.
- Some crude baking process, or changing the colors of some materials to evade issues.
Some use cases:
- Objects which “magically” generate their own light.
- Outside looking in through a window.
- Inside looking outside through a window.
- Being in a room that can see a corridor that is lit differently.
- Some objects have a light source, which is blocked from shining on others.