Hi Oblivion,
While adjusting the Bounds Scale will help keep the mesh in the scene longer it will hurt performance as you’ve already noticed.
There are two alternatives that can help with this.
- Create basic geometry outside of the walls that are loading in so that it’s not as noticable. This will block the light from flashing in on screen like this.
- Secondly, you can use the console command r.HZBOcclusion 1 that will use an approximation based on the size of the mesh for culling.
Using the first method will honestly be the best solution in situations like this where you want to block the light in interior spaces with out as much overhead.
To debug some of the occlusion issues you can also use the console command (Editor only) for r.VisualizeOccludedPrimitives 1 to see the bounds of these meshes when they are occluded vs in scene view.
I hope this helps.
Tim