Mapster32/Polymost: Texture (DEF) tiles can cause the 3D Mode rendering to freak out

While in Polymost mode, if you go into 3D mode while viewing a glowtile, then the next time you enter 3D mode the textures will freak out, see the video.

https://www.youtube.com/watch?v=ai5IYEAwJuQ&feature=youtu.be

When you then re-enter 3D mode after not having viewed a glowmap, the textures return back to normal.

The following zip defines glowmaps for the Octabrain actor and can be used to test this bug: octabrain_glowtiles.zip