Texture res vs polycount... ?
polycounter lvl 9
So I've been working in the animation industry for several years now but no game art until semi recently. In general animation, you add enough polys to make the model look good and you use a high enough texture resolution so the texture doesn't fall apart in terms of detail. So there's no real guidelines. Because its CPU rendered and doesn't have to happen at 60fps. Of course optimization is important, but not at the cost of quality.
So my question is: is there any sort of rule of thumb that anybody uses as far as texture resolution to tri count? IE: the LPC going on right now limits are 2k tris and a 512x512 map. Extrapolating from that would it be safe to say that a 4k model would/should use a 1024x1024 map? I know its also dependent on the size of the tri's and other factors (game engine, platform etc). I'm just looking for some sort of starting point for when I'm working without a predetermined tri/texture budget.
-David
So my question is: is there any sort of rule of thumb that anybody uses as far as texture resolution to tri count? IE: the LPC going on right now limits are 2k tris and a 512x512 map. Extrapolating from that would it be safe to say that a 4k model would/should use a 1024x1024 map? I know its also dependent on the size of the tri's and other factors (game engine, platform etc). I'm just looking for some sort of starting point for when I'm working without a predetermined tri/texture budget.
-David
Replies
Generally it depends on how close you can get to the model and some other factors. For example, a prop you can walk right up to might be 1024, but one on the ceiling of a tall room might be 512. Screen-time is important too. A hero character or first person weapon might get a large texture like a 2048, while NPCs or third person weapons would get smaller textures. It's all situational.
Don't forget that on most modern platforms, triangles are very very cheap to use. Triangle count is only a real problem on platforms with very outdated hardware, such as the Wii, handhelds, or mobile phones.
Usually when I'm working without a budget I like to texture big so it can safely be scaled down, but working on actual size is optimal whenever you can.
You can have a 512 on a flat plane that is only 2 tris or one that is a thousand tris. Texture size isnt dependent on tri count. Obviously the thousand tri plane would be more expensive but its not related to texture sizes.
Most guns actually use 1024's. Most common used texture rez's are 512's for games today. Most props, depending on how big they are would be a 512, some times lower and in some cases 1024's. Really depends on how big the prop is and how close you can get to it.
Also remember some things are made up out of multiple shaders/textures. This increases draw calls though. Characters are generally broken up this way having a 1024 face and 1024 body. Same with vehicles and other objects of that nature.
A good place to look for actual in game texture rez's would be UDK. Its free and the info like texture rez is easy to find. But be carefull. A lot/maybe most textures in Unreal are imported at 2048 which might lead you to believe that that item is using a 2048. This is not the case at all. You want to make sure you read "Max In-Game" this is the maxxium possible rez you will get from this texture.
So it might have been imported to the engine as a 2k but that is just how it was imported. Max in game is all that matters.
Most all of Unreals 2k imported textures are Maxed at 512 for props and 1024 for tiling textures. Unreal also have Max Xbox and Max PS3 which can differ from regular Max In Game which would be PC.
Like Racer said, always better to go big and down rez. Plus most folio stuff you see people use ridiculous texture rez's for objects.
A Games characters/vehicles/etc are the main focus. So they get lots of poly's and nice textures. A game prop that pops up now and again in the game needn't be all that detialed unless the camera gets very close to it or its a focal point in the game. Environments should have larger polys with textures that are big enough so that they dont stretch or tiling isnt obvious. So its mostly about using good judgment.
What I will say though. Coders aren't that bothered about polycounts being too high but they get reeeeaaally upset about wasted texture space and textures that are too big. I suppose that might depend on what engine you're working on. My rule of thumb with textures is start big and when the coders shout at you...reduce them. Its better to reduce and optimise than add more detail later.
http://www.ericchadwick.com/examples/provost/byf1.html
related pic:
Some good threads...
FAQ: Game art optimisation (do polygon counts really matter?)
How many textures per model is too many?
Some wiki articles...
Game Rendering Primers
Polygon Count