so, what it feels to me is like a vis problem.
Some brushes may overlap eachother on a 0.01 unit which causes the compiler choose between both of them.

Isn't there a command "force all brushes on grid" in Trenchboom? 

In TrenchBroom, under the Edit menu you will find Snap Vertices to grid and snap to integer. 

Are there any maps with identical versions for both Quake 1, UT99 and/or UT2K4?

I've been reading about Q3A to UT map converters, but I'm not sure if that would work well for Q1 maps:
https://ut99.org/viewtopic.php?t=2799 

For long time now i ask myself how you guys to angled brushwork in Radiant, like arches that lie on 45°, 33° or any other weird angles on the grid.

A great example for what i mean would be the huge chains in czg's q1 map Honey.

I try avoiding building stuff on grid 90° on grid an then rotaing it, as this brings the vertices off grid.
Some stuff i manage to do via a mix of csg_subtract and clipping, but for more complex constructs my brains 3D projecting algorithms fail ^^'

Are there any "cleaner" methods to do it? 

i did a post here once about "magic" (aka on-grid) rotation, but fuck knows where that's gone - same technique czg did for those angled bridge ruins in saint.bsp

These days though, misc_external_map is your friend for a lot of this stuff...

http://ericwa.github.io/ericw-tools/doc/qbsp.html 

i could do it with .ase geometry, as i am using Darkplaces with q3map2.
It's for a total conversion and use advanced features of both.

In some cases using .ase or a model instead of brushwork are not practical, at least that is what it seem to me.
And i guess the main problem in what i am trying to do is not the brushwork and it's limits, but my geometric understanding of things.

Here some screenshots of things i try to do:
https://imgur.com/a/Eg0E4ry

Maybe i asked even the wrong question, so i rather ask: how would you guys do that stuff depicted in the screenies? 

If you are doing stuff for the q3bsp format then it's a pretty good idea to use meshmodels/ase to work around the times when brushes just won't cut it.

For "seamless" joins of arbitrarily rotated meshmodels to surrounding brush geo, you'll want to use some artistic license and design the model in such a way so you have some "wiggle room" to be able to butt things into each other a bit and not look ugly - e.g. hide the joins with some raised trim or raised brick quoins or something 

I will for sure use that approach for more complicated geometry.

Just saw that screenshot of Wrath: Aeon of ruins in another thread:
https://imgur.com/Qg3VSqU

Would be interesting to know how that hall, especialy its in multiple directions facing door arches, where made.
At least that domed ceiling would be no problem with a trisoup.

PS:
Is Sock still around? 

Built this ship for someones map and I wanted it to be a rotate train. I got it all working fairly well despite some tuning I can do later. But for now I have this movewall that doesn't rotate. So if you ride the thing straight or fairly straight everything is fine. Once the boat turns the func_movewall doesn't. Is there a way to make the rotate_object solid so I can remove the movewall entirely?

A video showing it does work on my server.
https://drive.google.com/open?id=158gR5W8kGsF8pER2jKuH7wUifnlQOuv0


A link to the bsp. It meant to run on teamfortress with hipnotic ents added. So that means megatf and custom. I haven't tried other mods to see how it works.
https://drive.google.com/open?id=1JP77gLYtk6RX0D6FpH84gemy13pCwzeN 

bsp collision can't rotate without an engine feature. (this does exist for some engines, can't remember which, but Baker had it in MarkV I think?)

The movewalls are basically a hack to get around this -- you actually need many small movewalls, each one will not rotate, but the positions of them all will orbit the origin of the object to sort of make it work. For example if you put a movewall for just the mast of the ship, it would correctly move with the mast. Warning: You will need a lot of movewalls. 

Yes, I read through preaches site on all this. The server I intend it to run on will be FTE. I wont do the many funcwall thing, but I appreciate you suggesting. It would take way to many to simulate what i need here. I am pretty sure it can work, a non solid into a solid, but setting movetypes and avelocites blows my mind. 

Dear skilled mappers,

As a beginner in mapping, I'm facing an unexpected (but probably well known?) issue.
The number of monsters and entities in my map is quite low, and anyway far below the standard number in the original editor's maps.
The original game's maps display without any problem, whereas my map doesn't: it seems a threshold is reached concerning the number of monsters/entities and the most recently added ones are not displayed (as a player I am attacked by an invisible opponent, an invisible brush entity blocks my way, etc.) The entities beyond the threshold index behave normally except they are not drawn by the engine.
This occurs very soon in the mapping process, even before I really start to populate my map with monsters, as if all the available slots for entities would already be taken by doors, lifts, lights, artefacts or whatever. Yet the number of those is, once again, really low. Especially compared to how many entities are found in the game's original maps.

Any help would save not only my day but weeks of work, actually.
Thanks a lot in advance!!! 

This could still be any number of problems afaik, so lets narrow it down:

Which engine do you use?
Even "standard" Quake could mean three different ones: DOSQuake, WinQuake or GLQuake.

What mapeditor and compiler are you using

Have you tried loading your map in another engine and see if the problem persists?

How many entities are there actualy in your map?

Are your sure your map does not leak? 

Make sure your map does not extend past + or - 4096 units on any axis.

If it does and you can't shrink it without negatively impacting your map, compile it with the "-bsp2" command line parameter (for bsp.exe) and run it in a modern engine.

Also, if your map has lots of entities it's probably a good idea to make sure you're running protocol 666, not protocol 15. 

A usual Q1 map can have 37678 brushes and 640 entities. If you have less, than another error has faulted. 

Are you sure there are no "empty functions" in your map, like a func_door without arguments? It is easy to add a func and forget to add arguments. You would hardly notice.
Most times these cause a "too many edicts" error. 

Thank you for your quick answers :-)

I actually map for Hexen II. The only engines supporting it that I know are Ultimate Quake Engine 1.13 and Hammer of Thyrion. I have the problem with both of them.

My map editor is Trenchbroom 2019.6
My compiler is ericw-tools-v0.18.1-win32\bin\qbsp.exe

Without counting the world, there are currently about 220 entities in my map which is probably far below the limit (although I don't know what that limit in Hexen II is compared to Quake's 640).

My map IS actually leaking. Good guess Wakey! I would have never thought about that because it seemed to me that leaking problems were far behind for a while... and I must confess I still can't understand what the problem is. I open the pts file and carefully follow the "leak line" in TB but at the places it goes from inside to outside, it simply goes through solid world brushes and not between them through unnoticeable interstices as usual leaks do.
So now I know it's about leaking, but I can't figure out what the leak is.

Shall I very humbly and respectfully submit my map to one of you to get their insight and improve my understanding please? I would be most grateful for that!

@Shamblernaut: the actual count of entities doesn't seem to be the direct responsible but as a side note, what are protocol 666 and protocol 15??? 

your map does not gave to be open anywhere to leak.
An entity by mistake placed into the void can cause a leak too.
At least thats true for q3bsp, so i asume that is a valid statement for q1 maps as well.

What shamblernaut was talking about are different network protocols.
15 is the original, 666 is an enhanced one, by Fitzquake methinks.
It's important because Quake works with a client-server protocol, so even offline in sp the gamecode communicates internally over this. 

if you're mapping for Hexen II then the protocol 15/666 question isn't relevant. 

Leaks can be very tricky. Following the pts file will lead to the initial brush, but it always starts at one corner fading on a irragular vector into the void.
Very useful to set the sky brush dark and look with a 3d viewer along the pts line.