General Detail, structure brush distinctions.

[amz181]

ok. Ive seen those screens that show the difference between structure and detail. However im still quite confused.

from my current understanding structure is the bare base structure. All walls, floors and ceilings connecting to the void... Im pretty sure this is wrong though

so a little help.

Say you have a train in a tunnel. Would any part of the train need to be structure or would the tunnel just need to be structure?

[Plague Bringer]

Just the tunnel (unless the train starts in the void).

My understanding is that your understanding is correct.

[amz181]

thanks so much!
ive been puzzling that for months i dont understand why noone says that in the first place

[UniqPhoeniX]

Open a .prt file (that you get from compile) while the .map is open (in radiant plugins prtview). This shows how the compiler splits the map into areas, and in game it only draws those areas that are seen from anywhere in the area you are in (even if you can't see it directly). You would want as few splits as possible, while still keeping all rooms separated (otherwise the unseen stuff will be drawn). In game you can use /r_showtris 1 to see what is drawn from where you are. So lights and other small things need to be detail to not cause the room to be split into 100 areas.

To answer the question, in your case train should probably be detail.