To bring the store models into the game engine, Unity, I “baked” all of the shadow data into the textures and exported FBX files of the geometry. Unity supports easy texture remapping and import of assets created in Blender.
Baking shadows meant that I could completely shut off Unity’s realtime lighting system and rely solely on unlit textures. This is huge for performance, but it’s only possible because my scenes are static. The lights in the store never shut off, and you can’t rearrange the tables. Put more simply, if you were to pick up a MacBook from any table, it would leave behind a shadow “stain.”
This entire project was completed on my M1 MacBook Air with no external hardware or render farms. Baking the shadows at Apple Fifth Avenue took about six days, after which I was left with a fully-lit model to pan and zoom in real time: