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FPS Killers List em
Posted: Thu Jul 03, 2003 7:49 am
by Gen Cobra
Well I really need some thoughts from those in the mapping community regaurding the biggest killers of fps. Please list any thoughts you may have on the biggest cause/'s of a drop in fps.
Thank You
-GEN COBRA
Posted: Thu Jul 03, 2003 8:08 am
by jv_map
Poor vis design.
Posted: Thu Jul 03, 2003 9:46 am
by Surgeon
Many models in a small area
Posted: Thu Jul 03, 2003 11:55 am
by Bjarne BZR
Seeing far away in a complex environment.
Posted: Thu Jul 03, 2003 2:26 pm
by nuggets
more structure than needed, make as much of it detail as possible
loads of LOD terrain
more ingame ai/bots/players
Posted: Thu Jul 03, 2003 2:47 pm
by Slyk
-Bad brush work i.e. 'Z-fighting' of overlapping brushes.
-Lots of patch meshes, curves, terrain patches in small areas.
-Lack of VIS LEAF GROUPS. Large outdoor areas CAN be done (Gun Assault) and keep good FPS, even with nearly 100% LOD, water, etc. BUT, you need to plan carefully and make use of VIS groups everywhere possible. Plan your farplane distance and work accordingly with VIS groups.
-Detail lots of stuff, anything not blocking a fairly large field of view, broken walls, trim, non-enity brushes forming window/doors/steps, etc.
-You CAN have large amounts of destroyed chucks laying about with LOD and such, but detailing, VISing and such all must be combined. Use the 'r_showtris 2' command to try to narrow down busy areas.
-When using VIS, don't have large brushes cross from one VIS leaf to another. This negates the VIS leaf advantage for that brush. Each VIS leaf ONLY hides what is entirely INSIDE it, so any protruding brushes are uneffected and add to your vis count. I find keeping sizes to a max of 1024 units works best. Make multiple brushes if necessary for longer runs and VIS accordingly.
-Sometimes you build something that looks like it will kill FPS and if you mix up the tools you get good numbers, and other times you think it should be smooth and you get horrible FPS... really a crap shoot of design that you need to go back and rework over and over to tweak the FPS. In my SoS1 map, I thought the FPS would tank...and it runs 80+ in virtually every area because of using all the methods mentioned... AND
-'caulk/sky' texture: IF you are really hurting to bump FPS, use this texture on your sky box. Ain't pretty, but you might gain 20% or more. It allows the engine to blend the fog/farplane smoothly with the sky and helps fade in/out your brush work. Eliminates 'popping' in/out of brushes at a distance.
I could go on and on, but that's some on my experience over the last year.
Posted: Thu Jul 03, 2003 5:29 pm
by Gen Cobra
Thanks for all the info people. I really needed to hear a lot of that.
BTW I thought making something detail would only lessen compile time?
Posted: Thu Jul 03, 2003 6:53 pm
by chris_in_cali
What does setting brushes to detail or structural do anyhow?
Posted: Thu Jul 03, 2003 6:59 pm
by Alcoholic
by default most brushes are structural its in their properties. read this tutorial on detail brushes.
http://www.planetmedalofhonor.com/rjuka ... orial.html
Posted: Thu Jul 03, 2003 7:10 pm
by chris_in_cali
Thanks a lot, that was helpful, but I don't quite understand how changing the setting has such a profound effect. There something said about structural items being compared against eachother, but I'm not positive on how setting the item to detail removes it from this comparison but remains a solid, visible object. Does this have to do simply with being used for the lightmap or not, or what?
Posted: Thu Jul 03, 2003 7:15 pm
by Alcoholic
vis runs through your map and says "ok if i stand in point a, i can see point b, but not point c. so when the player is at point a, ill draw point b, but not c." a detail brush is just one that vis passes through. if you have a solid brick structural wall, vis will say "ok i cant see past it to point b, so i wont draw point b from here." if you made it detail, vis would say, "ok i CAN see thru it to point b, so i will draw point b from here."
Posted: Thu Jul 03, 2003 7:19 pm
by chris_in_cali
Oh God. I can see how complicated that sample staircase would make things. Thanks a lot.
Posted: Fri Jul 04, 2003 12:07 am
by nuggets
staircases, handrail's, ladders, shelving, etc...
all these kinda thing just make detail, making it detail saves on compile time bcus there's less vis areas present...
imagine drawing a brush in XY view
______
|........|
|........|
|........|
that's 1 vis area, 6 faces, 8 vertices and 8 edges, simple enough
but if you were to add another brush ontop of it, say a column
______
|........|
|...[]..|
|........|
that'd then create 4 vis areas on the 1st brush
______
|.....|..|
|..|[]
|_|
|..|.....|
bloody hell that took some working out, but just by adding a second brush in the centre to one existing one, you've just multiplied the visdata by 5 on the one face
making it detail however, will not change visdata, so it'd stay as 1 vis area

Posted: Fri Jul 04, 2003 8:09 am
by bdbodger
I read that when vis is done it keeps cuting the map into volumes that do not contain structual brushes so more structure more cuts , a small brush will create a lot of small cuts that vis will have to deal with to see if the volumes can see other volumes .
Posted: Fri Jul 04, 2003 12:19 pm
by panTera
[
http://www.nibsworld.com/rtcw/tutorial_ ... art1.shtml]
Some good tips from the guys here, but I'd just like to add that if there's one thing you should always try to avoid is using loads of tiny brushes in (wide) open areas. Sure, in a somewhat closed off hallway it might not be a problem, but when there's loads of tiny 'crap' for the engine to render at a distance it'll bog down.