Looks like the draw code is not calling glcolor(1,1,1,1) (or setting the uniform equiv if your using shaders) before drawing?
(Or maybe code that changes these values should be responsible for restoring them? It saves a few calls)
(I would like a feature to draw trees at 50% alpha, buildings 60% alpha and the sides colour-coded like this, toggled with a hotkey. I keep losing my soldiers on treelines, especially when they pursue an enemy without me noticing, and they take some finding)