That's awesome. :) I'm aware of the texture/sound bug, but just didn't put that together with how the placement dome gets drawn. Very cool!

I get texture corruption sometimes (only in Source-engine games). The pattern is a recurring sound-loop (the same half-second of game sound plays over and over) - when the game finally recovers, it appears to be very confused about where various textures get stored.

The results are often pretty wacky - this one is the dome showing the detection radius when placing a turrer, which has gotten replaced with the engineer texture from the class-selection screen.

wut