I'm a newbie in mapping (I'm better at skinning, that's for sure 8) ) and I've got a question. Why should I caulk the surfaces that aren't visible? I'm not sure, but I think that VIS is computing also the surfaces that aren't visible, and caulk texture 'tells' VIS not to compute the surfaces covered with it, so caulking speeds the compile up, is that right
[EDIT - jv sneaked in before me, while I was typing]
The caulk texture prevents the game engine from rendering any side of a brush textured in it. Normally back sides of brushes hidden away and that can't be seen can sometimes be rendered, this is a waste of resources, i.e CPU / GPU time is wasted making calculations about this particular part of the brush. Caulk prevents this, increasing the performance of the map.
Vis doesn't calculate this, I would assume its done when the bsp is compilied rather than done in real-time as the map is running, because the resources saved not rendered a side would be lost calculating that the side wouldn't be rendered.
Anyway Vis works out portaling, this makes it so the player never sees 'the end of the world'. We don't want the entire map to be rendered at once, Vis splits up your map into sections, where sections only visible from one another are rendered at any one time.
I'm working on making my first map myself, but I've been getting good advice from here, TMT, and from Balr14. One of the first things I've learned is just for good habit, create your brushes in caulk then change as needed. This way you won't accidently texture a side that will never be seen.
hmm.. but i must create the brushes with caulk, and then I only need to select the sides that i want to be textured, or can i just select the whole brush and then texture is ?
Check my post, Wow that's a big caulk, and look at the pic. I run itno these little flicker lines. AND IT'S NOT from overlapping brushes. I hate caulk sometimes but it is very useful for compiling. Right click every brush that you aren't gonna make into a window or scripted object and select either make detail or detail from the drop down menu. THIS helps compile time. Caulk helps too, but I hate dealing with it.
First, always use 'make detail' and never never never use 'detail'.
Moreover, you'll need caulk in any map. It really isn't difficult to deal with. Flickering lines are never caused by caulk. They're caused by sloppy brushwork or invalid faces.
To texture one face, select it using ctrl+shift+click and then texture.