Texture Atlas help

[Brad Dibble]

I searched through the postes in this forum, and have read several refrences to creating texture atlases, but have not seen any explanation on how to create one. Does anyone know of a toutorial for making one? Is there some software (free software) to construct an atlas? I'd like to know more. Any information would be helpful.

 

[martinez]

Say, making a texture atlas is only graphical work. You need a program which can work with layers. Then free program can be Gimp for example.
You put all smaller parts on one texture (document/work area/image howerer you call it) - keeping them on layers allows you to make corrections much more easily. At the end - flatten the image or merge layers and save as dds (or jpg) - remember that the texture should be in "powers of 2" (2x2, 4x4, 16x16, 32x32, 64x64, 128x128, 256x256.... and so on).
Texture atlases are good solution when you want to use less materials - many objects can use the same texture, which makes the same (and only one) material for all of them.
Then it's a matter of making new objects (in Sketchup, Blender, 3dMax or other programs) - all of the objects will use the same texture atlas.
Merging the materials has to be done in XPacker (he always adds new material any time you add new object to the xpack). If you don't know how to do it, I will write about it here later.

 

[R Soul]

For your own objects martinez is right, but objects from other XPacks tend to use lots of small textures.

There appears to be a texture atlas tool on NVIdia's site:
http://developer.nvidia.com/object/texture_atlas_tools.html

I haven't used it but might give it a go at some point.

 

[martinez]

Interesting, R Soul, thanks I don't know about "batch files", there was something about it in rF's threads.. Anyway, I will check what is the NVidia's atlas tool.

 

[Pangaea]

if your working in max this might come in useful for you
http://www.scriptspot.com/3ds-max/scripts/texture-atlas-generator

 

[martinez]

What Ehrlec says about non-power of 2 textures is true, but (shortly) when a texture has no mip-maps. A good example can be "LIDI3D.dds" from GB XPack. Anyway, I always keep textures in powers of 2 and never have any problems.
I wrote not very precisely before - the parts of texture atlas can be any size, then finally the whole atlas I would make as powers of 2 - not necessarily square - it can be rectangle too - like e.g. 128x1024 or 2048x512. In case I would want to use mips - they would always work well.

@Pangea - thanks for the link to the scriptspot.com

 

[Lamda]

it can be rectangle too - like e.g. 128x1024 or 2048x512

it´s true, no problem with it, but for RBR original file form tracks it should be whole square (it´s loading quicker).
A good strukture planing saves time during modeling/testing. It isn´t possible to use multimaterials in original file form yet. So all meshes with different texture base must be detach (only unweld is not enough). so the best is to thinking about texture organisation before start maping. I actual make for every objectgroup (for example treewall,vegitation,houses....) a own *.dds atlas (by handwork) and and add a own layer at 3d for every *.dds. so i can quick export and test (partwise too) and i find easy my needed objects.

If you want to convert BTB to original file form, best is to make own X-pack with own dds. otherwise you have very big rbz file with many non used texture parts (my rbz is aprox 70MB per weather definition= 210MB per daytime definition). If you made quick n dirty at btb, you will lost double time because remapping. Sometimes i use single texture files, because its easy to use for map uvw (unwrapping cost much time for pattern texture parts, maybe therefor it must add new polygones)

i hope it can help to avoid double work

Lamda

 

[Brad Dibble]

Thanks for all of the information, This is all new to me, so I appreciate the help greatly. I'm still a little unsure how the Texture atlas is created. I have used one .dds file with two or thee textures on them, but I made them by placing UV unwrap coordinates in a specific place in the Max unwrap window then combining the images in photoshop. My method would be difficult to use if I was to have a large number of textures because I have no way of aligning them accurately in the max UV unwrap window.