Removing planes

Freestyler · April 2002

<div class="IPBDescription">...</div>While lying in bed this morning (ah, the joy of holidays) I thought about ways to remove planes from the maps. The best idea I came up with (apart from good mapping and brushwork) was the idea of removing them in the compile tools. Is it possible to make faces textured with NULL be removed from the plane count or is this just a wild dream?

If this could be done, think of how much more coudl be added to the map if the only faces in the plane count were only those that were visable...

Muu · April 2002

I personaly cant think of any areas in my map where this would be usful and not cause leeks - which I assume it would where the brush with the null texture to hit a retaining wall.
I think that poeple can still reduce plane count alot by choping thier brushes sensibly and using the right size/scale of texture.

Nemesis_Zero · April 2002

After checking NS_Eniants latest .rmf I came up with about 1000 planes that could be cut that way - every plane that faces the void (and they <b>are</b> counted in) could be counted out that way.

Relic25 · April 2002

Merkaba informed me some time ago that this very subject was discussed in depth with Merl, the guy who made the customization of Zoner's compile tools. The verdict was that it just wasn't possible, unfortunately. If it were, it would have helped me a lot too.

Muu · April 2002

Nemisis are you saying that planes that face the filled areas of the map are not removed?

Relic25 · April 2002

I'll field this. <img src="http://www.natural-selection.org/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'> They are eventually removed, but not in the CSG part of the compile, and that's where the planes are counted. As proof of this, I had a bunch of solid brushes as 'fillers' between rooms and hallways when I was building ns_bast to suit the old commander mode. Even though these faces dropped out under the new commander mode (since they are 'outside' of the map), when I removed them, my plane count dropped by about 50%. CSG calculated the number of planes based <i>only</i> on all of the brushes in the map. No culling of faces is done at this point, so CSG can't ignore faces that will eventually be culled or face the void.

Muu · April 2002

Thanks Relic but I already knew that, I wanted Nemesis to clarify his post because the way I read it made it look like he was saying the faces aren't culled - which I already knew was false - any I know Nem isn't stupid so I assumed that I had miss read his thus I asked him if he was really saying what I thought he was saying - but I perhaps didn't make the intention of my question clear - because I was quit busy at the time <img src="http://www.natural-selection.org/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'>

Yamazaki · April 2002

There is a way to reduce planes that involves working with the outside faces of your map. Since planes are counted before any culling is performed, you should try to make the outside of your map as evenly as possible. This means extruding all those wall, ceiling and floor brushes so that the outside of the room looks like an even box. You should also avoid mitering corners, unless its necessary for getting that 'cornered' look in your texturing. Mitered corners don't reduce r_speeds anyways, and they just create a few extra planes according to some research Merkaba did a while back.

Relic25 · April 2002

That's an interesting method Yamazaki. I hadn't thought to try that, but it makes sense.

Flayra · April 2002

I was talking with Ido from Valve at the GDC (cs_havana in CS 1.4) about this very topic. Maybe this is obvious to everyone already, but if you work with a coarse rotation snap value, you'll conserve on planes quite a bit. The problem is the total number of plane <b>normals</b> I believe, not planes themselves. So if you snap to rotation, you'll have your faces generally using the same planes, thus not using as many different ones.

Tzarcon · April 2002

Uh, sorry about not knowing this, I'm a bit rusty on my Mapping Lingo. But, what are planes?

Moleculor · April 2002

I believe they're the things that make up brushes... the sides of the box, if you will.

Relic25 · April 2002

No problem. <img src="http://www.natural-selection.org/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'> Planes are just planar extents parallel to the faces of all the brushes in your map.

In the attached picture, the yellow boxes are brushes. The blue represents a plane. If two brush faces are perfectly parallel and aligned, they will share 1 plane instead of each having to make its own plane.

Tzarcon · April 2002

Wow! I never knew that

/me goes back to ns_shadow and changes everything to lower r_speeds

Freestyler · April 2002

DO the 2 aligned faces (like on the image) still only make onne plane if there is a gap between them (also like those 2 yellow boxes)?

Relic25 · April 2002

Yes. They will share that plane between them. In fact, in that particular example, those 2 boxes would share 4 planes between them - 1 for each side.

Tzarcon · April 2002

Right. So, does that mean that if you extrude all the brushes on the outside of your map, will it significantly reduce your plane count?

Like in the picture below. Will my plane count drop durastically when I compile?

And, does plane count affect r_speeds?

[EDIT] Congrats Relic25, you just hit 1000 [/EDIT]

Relic25 · April 2002

I'm sure it would drop some, as Yamazaki pointed out earlier in this thread. I haven't tried to test this myself, but it seems to be a reasonable assumption. I don't think the plane count has any direct correlation to r-speeds. R-speed considerations don't really come into play until the VIS step of the compile process, while plane count is dealt with earlier in the CSG step. As an example of how one doesn't necessarily affect the other, if you were to make a hollow box with a player start in it, then create hundreds of normal world brushes <i>outside</i> of this box, your plane count could be high. But, when the map is run, the r-speeds could be extremely low, since there are very few visible faces for the engine to render.

KungFuSquirrel · April 2002

Regarding Tzarcon's post, I think that will have a fairly nice effect on plane counts -- I have had a long-standing habit of having fairly clean aligned exterior architecture (originally just for grid cleanliness purposes), and more recently I've noticed that my plane counts (even on my larger maps) are much lower than I tend to expect. Perhaps this was a good habit to get into back in the day. <img src="http://www.natural-selection.org/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'> Or perhaps I just suck at detailing things, heh...

Merkaba · April 2002

The plane limitation is also a perfect reason why you should use one brush to do as many things as possible, and not split your world up more than necessary. Eg, two brushes making up a single wall will result in extra planes. (I'm not sure why you would split a wall up like that anyway though.)

Removing planes

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