I’ll have to touch the terrain rendering again to make culling work correctly.
I was putting lots of thought into this, but it’s now clear to me that the current API can never support modern features like GPU-based culling because it follows the D3D9/10 command stream model.
The new API will, instead of setting textures and vertex buffers, submit a list of meshes to draw. TFXplorer can then internally build GPU-compatible culling data from this.
This will really push us into the million polygons range; I hope that it will also remove some of the ugly culling code from the DID F22 extension.