The following is a little article submitted to us by a visitor. Pretty interesting, about HINT brushes and interplay of sky textures and map areas.

Here's a little thing that you might run up on making Q2 maps... It has to do with the following scenario:

You have a section of your map where the player is in a area surrounded (on all sides and above) by sky textures.

IF you have any other areas of your map BEYOND this area or ABOVE this area - the player can 'see into' those other areas. An example of this is - say you have a cliff and the player can stand on top of this cliff. The 'walls' surrounding this cliff are textured with sky1. And WAYYYYYYY down below these cliffs, you have rooms that make up another part of your level. Given these circumstances, he can actually see down into those sections as tho he were in noclip mode. Not only that, but the rooms will appear to be roof-less - that is, he can see other players (monsters, weapons - whatever) milling around down there. The same effect happens on a horizontal plane as well - he would be able to 'see' thru the walls of any rooms parallel to the area he is standing in - ONLY IF he is standing in front of a sky brush.

Think of it (the sky brush) as though it was a window with X-Ray capabilities.

I tried all kinds of things to get rid of this and the only thing that actually worked was to replace the sky with some other texture (such as rock or metal) - then there was no 'sky' to look thru.

BUT! Id software had this same problem and it IS very solveable.

Recently I was reading an article by John Carmack (?) about areaportals and hint brushes (brushes with the 'hint' textures on them). Now, I thought this 'hint brush' was just another kind of trigger that set off a message that gave the player a hint, like 'You can kiss your ass goodbye here'.

Not the case at all.

Carmack was talking about Hint brushes and the VIS process and how hint brushes can reduce the number of polys VIS 'see' when it's running and therefore reduce VIS time.

VIS process time is NEVER a problem for me. I build large, complex levels and never have long VIS times. I once converted a level that was taking 24 hours to VIS and had it VISing in less than 3 minutes. If you wanna know how I do that - write me.

Anyway, I was experimenting with some hint brushes in an outside area to see what VIS would do. This area was BELOW a large portion of the map some 3600 texels above the ground I was standing on. And, of course (just as I suspected), I could see thru the floors of all those rooms far above me thru the sky over my head.

I added the hint brushes (cursing the fact that I'd have to add some stone walls or something to block the ghost-view of the rest of my level) and let it compile. The .map file is nearly 1Meg in size, but it only takes 90 seconds for VIS to run. And, with the hint brushes added - it still took 90 seconds.


I thought this was supposed to DO something for me. Ah, what the hell, let's go see if it looks/plays any different...

The FIRST thing I noticed was that ALL my ghost-rooms were GONE!! I mean not even a 'hint' of them anywhere.

So I made another little map and placed some blocks out in the void down below a cliff area that I surrounded with sky. Compiled it - ran it - and sure enough - you could see all the blocks I created down there.

Then I went back and added a hint brush in front of the sky (it's invisible, you know - like a clip brush but you can walk thru it) - recompiled - re-ran and Voila! no more blocks in view.

So, if you ever run into this - you now know what to do.

Cya later, Imaginos - called Destinova - the Magna of Illusion