Sky And Clipnodes

Bronto · February 2003

Does haveing a skybox add to the number of clipnodes? Because I am about 2/5 done with my map but I have 65% of the clipnodes full... Arg
I know the clipnodes are the space inside your map, and that there are a couple of ways to get this lower, but most of them won't help me enough.
If anyone has any easy good tips to lower clipnodes, it would be greatly apreciated.
Thanks

Confused · February 2003

removed

Confused · February 2003

if by sky box you mean you have a big box around teh map yes.

any space a player can see/ get into add to clip nodes

clear?

Bronto · February 2003

No, I just used the sky texture on a brush at the top where walls end. And where a ceiling fell down, reveailing sky.
Ignore the first part, I figured it out by just retexturing the brush and compiling to see if the number of clipnodes are the same.
I havent used big boxes in my maps for a long time, which is a good thing <img src='http://www.unknownworlds.com/forums/html/emoticons/tounge.gif' border='0' style='vertical-align:middle' alt='tounge.gif'>
The only recent time I used big boxes to stop leaks was from a stupid genserf error where the leak was so small that is took me like 8 hrs and I still didn't find them all. That was like a year ago on a single player map I was working on.

Killtoy · February 2003

Okay, I'm a bit out of the mapping mindset these days, but here goes:

Don't use "SKY" on non-sky brushes anymore. "NULL" is a better alternative.

As for skies and clipnodes, I could explain ways to try to reduce them, but I know there are a half dozen tutorials out there that do a much better job than I - making use of illustrations and such. Do a search and see what you can find. Still have questions, bring them back here.

But the best advice I can give any new mapper is this:
Get in the habit of searching for your own answers. Typically, the tutorials available on the net are much better than anything you will get in a forum. If not due to the fact that they generally include illustrations and examples, they also tend to come from more experienced sources. So get on google and good luck!

(I'd throw in links here, but I'm not on my own PC, and so I'd have to take some time getting them together. Look for Relic's tutorials, if they are still online. I recall him having a good one on this subject.)

Relic25 · February 2003

Sorry everyone, that tutorial is no longer available through me, since I took down my site. You can <i>probably</i> still find a copy of that tutorial at the countermap site, if it's still around. I didn't write that particular tutorial, but if I recall correctly, it was more to do with vis, not with planes.

Put as simply as I can, each face of ANY brush that you create will add to the plane count, unless it is perfectly parallel <i>and aligned with</i> another existing brush's face. It doesn't make any difference if the face in question will be culled out later during later stages of compiling, since the planes are counted before this culling takes place. Unfortunately, this also means that things like using the null texture will not lower plane count (they do have other benefits though).

**EDIT** Doh. I wrote the previous stuff only to revisit the initial post to remember that clipnodes were the issue, not planes. Using the null texture WILL help this.

Cagey · February 2003

</span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> (Relic25 @ Feb 27 2003, 03:56 PM)</td></tr><tr><td id='QUOTE'> It doesn't make any difference if the face in question will be culled out later during later stages of compiling, since the planes are counted before this culling takes place.

<snip>

**EDIT** Doh. I wrote the previous stuff only to revisit the initial post to remember that clipnodes were the issue, not planes. Using the null texture WILL help this.  </td></tr></table><span class='postcolor'> 
Actually, the clip brush generation code is in HLCSG, and the code to remove null faces from the vis hull is in HLBSP... since the clip brushes are generated before null face removal, I don't see why clipnodes would receive any benefit--the nodes define the inverse of the space taken by brushes, and the brushes aren't affected. You can see this in action by making a func_wall that is completely null textured: the wall will still block passage even though it's invisible.

Regarding the planes not being culled when faces are culled, my first tool post here (opt_plns, webbed thread) checks the face, node, and clipnode lists to cull unreferenced planes, dropping the total to just those in use... on most maps, over 60% of the planes aren't necessary.

Regarding the use of clipnodes for sky generation: half-life skies didn't originally generate any clip information, allowing you to jump upward out of the map if you didn't explicitly clip your skies. You can still duplicate this effect using the -noskyclip option in HLCSG, but I believe it would increase clipnodes if the clip hull couldn't be sealed, so it's mostly a curiousity at this point--of no real value to anybody.

Killtoy · March 2003

Hmm...

In this case, I suspect all that is needed is a little consideration being taken on how the sky brush is being employed.

Sky And Clipnodes

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