This error appears in multiple situations, if:
- Your map is not fully enclosed (it leaks).
Pantera wrote:
You get a backwards tree volume error instead of a leak when the compiler can't plot a course from the first entity to the point of the error, to place in the point file. This probably means the entity was exposed to the void. If it had been inside a building and the compiler could plot a course through the building to the void, it would have valid point file data and a leak.
- You have a bad brush somewhere. Hard to trace, possibly it's the terrain if you have some.
SOLUTION: Make sure you have a structural skybox if you're working on an outside map. In general make sure there's no leaks. If the error persists, you can use Rogue's plug-in to purge bad polygons. Just extract the file to a /plugin folder within your Radiant directory.