env_cubemap

How much is too much? As in, does it matter how many cubemaps there are in a level?

I have multiple areas of water that interconnect. Would just one or two Cubemaps do if all the water brushes are touching each other?

http://www.valve-erc.com/srcsdk/Levels/cubemaps.htm

<DIV class=quote>
<DIV class=quotetitle>? quote:</DIV>
<DIV class=quotetext>Because surfaces must approximate their surroundings via cubemaps, using too many cubemaps in a small area can cause noticeable visual discontinuities when moving around. For areas of high reflectivity, it is generally more correct to place on cubemap in the center of the surface and no more. This avoids seams or popping as the view changes.</DIV></DIV>

I would guess if it looks OK, go ahead. If you start to get bad contrasts or the light starts awkwardly fading, start removing (or just moving) them around. I know for a fact you can have like 6 env_cubemaps right next to each other to create a nice 'cubemap', so it just depends what you need them for. Just try sticking with one in the center unless it isn't working for ya...THEN add more.

If you want to connect multiple faces like that, then just get them all to share the same cubemap (the 'brush faces' property of the cubemap, I think it is- and just CTRL+click on the faces in the 3D window).