there's no official upper limit but probablty each engine or tool will break in undocumented ways when you make something big enough.

For example in GLQuake the limit is width x height <= 307200 

... or 1024x300.

So, in GLQuake, that's 1024x256 or 512x512 tops. Curious if there are engines that have raised other bsp/netcode limits but left that one. 

correct, the line of code looks like this:

static unsigned trans[640*480]; // FIXME, temporary 

lol 

Is it ok to make brushes with liquids (lava/water) intersect with world brushes, and go outside of walls? I've noticed that if I use multiple brushes for water the edges where the brushes meet becomes visible in-game. I've read somewhere to never let brushes intersect so were a bit hesitant to do so. 

Intersect away, no problem. 

made it one big lava brush, but the geometry around cuts it up on compile with quite noticeable edges... Any tricks to get around this? http://i.imgur.com/YVzHLKL.png 

I've noticed that if I use multiple brushes for water the edges where the brushes meet becomes visible in-game.

This shouldn't happen.

Nor should the thing in the pic you posted. 

No, the artifact in the picture is what happens with most modern rendering engines. That would look fine in the software renderer. 

Quakespasm get your shit together! ;) 

That would look fine in the software renderer

Oh, so it's a shitty GL rendering thing. Does this happen in Fitz / Quakespasm ? 

r_oldwater 0 should fix it, that'll be the default for the next QS release. 

r_oldwater 0 did the trick! Thanks 

when the texture isn't aligned across all the brushes. 

Is if liquid volumes touch sky, then the compile will break.

And yeah, r_oldwater 0 FTW. 

water and lava touching also cause a problem i think? 

and uh... slime too i guess. :S 

When would this even happen? :)
I guess if you were to make a horizon but, damn the size of the water brush would be huge! 

It's almost always a mistake. You copy a brush, move stuff around, etc. It happens. 

Make sure all water/lava face's texture attributes are 0 

Make sure all water/lava face's texture attributes are 0 

Which should be 1 

Point me to a .bat FAQ or whatever so I can make my compile a bit more clever.

I want to copy the mapfile, change some of the data within it (texture names for {) and then compile the copy.

Or... does your compile tool already allow for something like this Necros? 

the latest trenchbroom 1.x release can work with { textures, in case you were working around that.

Not sure about where to get a good bat file tutorial, sorry 

so, alpha textures start with "{" ...You're kidding me...how many tools does that break?