While testing this issue it was interesting to discover how the surrounding BSP's were affected. They seemed to clip/disappear according to the surface normals of the deleted brushes.

There is a simple workaround to convert your bsp's to static meshes after modifying the faces, and the surrounding brushes reappear and render as expected.

Steps to Reproduce

1. Open attached project.
2. Toggle Geometry Editing (Shift+5)
3. Select one of the larger faces on the long BSP brush.
4. Choose the 'Flip' option.

Outcome The surrounding bsps relative to the surface normal of the flipped face become invisible or get clipped.

Expected Only the bsp being edited should be affected in the viewport.

Have Comments or More Details?

Head over to the existing Questions & Answers thread and let us know what's up.

Login to Vote

Won't Fix
CreatedMay 1, 2017
ResolvedAug 18, 2021
UpdatedAug 18, 2021