Can't you also throw grenades through that? Just wondering. Shooting through is just fine, and if the grates are bigger than nades, throwing those through also is. Same applies to mortars and mines. But I do believe the grates are smaller than all of those, and being able to throw grenades on people on the second or third level without making them airburst would benefit your intended easy to capture, hard to defend gameplay.
What needs to happen is that empires needs to recognize grate materials as the other source games/mods do: as physical solids which permit the passage of hitscan bullets, currently such textures are treated completely solid by the engine, this could be part of the bullet penetration code present in other gameswhich empires seems to lack. Add this and the problem is easily fixed.
Don't you just edit the .vmt file and make it exactly as the other textures? I doubt that the game takes transparency into account. OR Add invisible brushes for each of the grates.
1. I tried this one already (the %compilepassbullets or something like that) and it didn't work. 2. This is what the map currently uses to allow you to shoot through the grates but still walk over them, unfortunatley its really entity intesive.
Looking around the middle now, you've really opened it up, it looks fantastic. Can't wait to play it properly.
This thread has an overview of those compile flags, perhaps another one could be of use ? http://www.interlopers.net/forum/viewtopic.php?f=2&t=33777