Be sure to check out the help file in About > Help for the basics on a lot of your questions.

If you still have issues post back! 

ok...
i quote from the help

"Note that you cannot change the number of faces of a brush by with the resize tool."

i missed that enterely. i think it might be useful. perhaps it's unnecesary, i don't know.
also, it's 'converging lines', that's what i meant.

--

"Alternatively, you can add two clip points at once by dragging with the left mouse."

and

"In the 3D viewport, you can only place clip points on already existing brushes, whereas in the 2D viewports, you can place them anywhere."

now i don't need to move clip points with the arrows.

--

CGS substracting is a question of the type of "is good practice or not?"

--

it seems that i can't snap directly to objects, so it's better to snap brushes to the grid and zoom if they are separated by 1 unit.
and using clipping, CGS and vertex. 

Glad to see the Help file ...helped!

As far as subtracting goes, I think it has come a long way...TB2 handles it fairly well. One thing I do is if I have an odd shape I plan to subtract, I will cut the brush into as small of a square as I can around the subtracting brush. That way there isn't so many crazy things going on after the operation!

For things like basic shaped hallways and such it it probably best to just create the brushes to form said opening. 

I can never seem to do arches with any consistency. It's not that the end result is bad but I just seem to do mine by trial and error. How do other mappers approach creating an arched doorway? I am using TB2 and would love to how others approach this. 

Ive had the outline for an arch tutorial in my head for a few weeks. Lemme whip something up for ya. I think itll make quick sense of the black magic of arches. 

That would be greatly appreciated. And it seems like we have some new blood on Func who would benefit from this too. 

At first i tried this:
http://imgur.com/a/xRJqg
angles: 0�,30�,60�

but i didn't like that the arch is narrow in the top

so i made a 30� brush, duplicate, flip horizontally, and rotate with alt+up
http://imgur.com/a/2edZv 

You've got the right idea and it's good to see you trying it on your own before asking for help!

TLDR: Triangles!

http://imgur.com/a/tmtmz 

*the angles are:
90� (vertical) ; 60� ; 30�

the brush is 30�/60� 

and the textures are aligned! i had to rotate 180� the textures of the two top brushes, but other than that...

i tried cliping in two ways, and in both the textures are aligned too. nice.

http://imgur.com/a/ax8oW

pd: yeah, absolutely no lights yet 

Thanks guys - this is really great and the key for me was slicing the inside corner (step 4). What I have been doing is clipping large sections of square shapes and "lifting" the vertices into position.

http://imgur.com/8YZlU6x

Clipping is so powerful when you see it done "correctly." Thanks again. 

Why is this here and not in the Mapping Help thread? It's not Trenchbroom-specific. 

My bad for starting it here, I honestly thought I had posted originally in Mapping Help but saw the replies here. Going senile. 

Mugwump: Refer to post #2408 in this thread. I gave an arch tutorial that specifically mentions "for TrenchBroom 2". He is 100% in the right to post a response here...cause...well thats where the discussion originated. The tutorial mentions keyboard shortcuts specific to TrenchBroom.

topher: im glad i could be of some help. curved shapes troubled me for quite some time. 

Honestly, I don't mind and it's not that big of a deal in the first place, but a) the question could have garnered more editor-independent answers than Mukor's TB-specific reply and b) I know people here can be a little sensitive over this kind of things. 

Thanks for sharing your technique Muk!

Would have been great to have had this when I was banging my head on how to create them last year! 

maybe we went a little offtopic

on topic
"face convex merging"
is this a feature? i didn't see it in the help

this software is very intuitive and full of shortcuts to save time

in a few days and aprox 6 hours of fiddling and some reading i'm getting confortable with shaping this simple brushes

http://imgur.com/a/IIcQ1 

Convex merge is a fantastic feature and it looks like you already got the hang of it! To be honest, I don't know if I realized face selection would work with merging but I assume it is intended.

Keep going topher! 

Is the lag when clipping a large amount of brushes at once a known issue?

https://dl.dropboxusercontent.com/s/f8im492wkzjic2a/2016-12-21_00-13-13.mp4

I ask because although I've been living with it for a while (like many tb2 bugs - I'm really bad at reporting in a timely manner...), the more I trisoup for this map, the more of my time it takes up. It'd be nice to at least have a "won't fix" response, but I'm skeptical of submitting an issue because it may simply be something that comes with the territory of the operation... 

I have encountered this before, sometimes it can happen with just a large brush that I am cutting in half. A bit random at times but infrequent enough that I never regarded it as an issue.

Doesn't hurt to submit an issue regardless. 

Seriously. I'm providing this app for free. The only price you have to pay is reporting the issues you find. Let me decide whether or not they are relevant. Don't sit on issues out of doubt whether they are issues or not. 

TrenchBroom-Win32-2.0.0-Interim-f7fe54e-RelWithDebInfo.7z 

Thank you! :D 

I have this irrational fear of annoying people by filling up their issue tracker... If I were running the project, I'd be obsessed with getting the open tickets down to 0 at all times...

I need to stop projecting. 

Noticing some... aliasing? is that the right word?

Noticing it on the version you just linked Eric.

http://imgur.com/a/MA4IL

JUUUUST opened it up so thats all I have for now. Ill be getting intimate with TB over the next few hours and Ill report back here or go straight to github with anything else.