How do I choose texture map size if the desired texel density is already known?

CognizanCe

I have a ranger lookout to texture which must have a [FONT=&quot]texel density of 256x256 per square meter.[/FONT]

I created a bounding box around it that's 6m wide x 20m high x 6m depth.

I'm thinking multiply the height (20) by 256 (the desired density),
which equals 5120, then round it down to 4096.
Is this correct?

AdvisableRobin

Perhaps you could elaborate a bit more on the mesh itself. Are you talking about texture atlasing multiple pieces that make up the ranger lookout. Or is the lookout a single asset?

Obscura

If its a tileable texture, then you just have to change the unit settings to meters, and probably then you can give in the uv size in meters (at least in max, but probably its possible in other apps too). If its a unique texture, then usually rounding to the closest po2 res works. if you want to be more accurate in the case of the unique texture, then you can scale the uvislands with hand to the desired size, but this will cause some unused space, which is wasteful.

Depending on the reference/requirements, tileables are better on buildings.

seb3d

not completly sure but my understanding is: if i.e. you have a 6m wide plane which fills a uv space/texture completly in u than you would need a 1536 * 1536 px texture to reach a density of 256*256 p/m². so it depends on you r uv layout compared to the world space scale of your object. hope it makes sense!?

CognizanCe

I THINK I got it figured out.



^^EDIT: that's supposed to say 1024 wide, not 10254)

Have 256pixelsx256pixels represent 1 square meter.
This left me with a 1024*1536 map, (incompatible because of the 1536).
-But 256 texel density was the MINIMUM desired density, so making it 1024*2048 makes sense to me.

y/n?

-It's a single asset.
-It's not tileable.
-What you said makes sense seb3d, but it has to be on a map that's a multiple of 2.

Obscura

you'll get too much stretching if you do it this way. Dunno if that ok to you or to your client though. if not, then you can apply what i wrote earlier. Or maybe it would worth to use 2 textures instead? One 1k, and one 512. together its a lot smaller than the 2k would be, so smaller size, less memory, etc.

CognizanCe

Obscura wrote: »

you'll get too much stretching if you do it this way. Dunno if that ok to you or to your client though. if not, then you can apply what i wrote earlier. Or maybe it would worth to use 2 textures instead?

I'm limited to one map.
As for stretching, keep in mind the UVs are gonna be proportional to each other. I just got a little more room to move them around and scale them uniformly while maintaining that minimum 256 density.
They won't be stretched vertically just to fill UV space.

seb3d

but it has to be on a map that's a multiple of 2.

yes thats for sure! didn´t even think about that it´s necessary to add this to my example.