Textures

[mito]

Is it possible to create textures for games using these pics? I wonder if it's possible to make a 3d map using them.

http://www.msbnet.com.br/pessoal/veritas/textures/paralelepipedo.jpg
http://www.msbnet.com.br/pessoal/veritas/textures/calcada1.jpg
http://www.msbnet.com.br/pessoal/veritas/textures/calcada2.jpg

 

[soylent]

Sure, but they are horrible pics to make textures from and will take a ton of work to get even half way representable textures. You want shots perpendicular to the surface and as little distortion as possible(i.e. you want to be quite a bit away from the surface and using higher zoom whenever possible).

Then you need a decent image editor, e.g. photoshop or similar(gimp?). Or you won't be able to create a texture that tile nicely.

I really have no idea how you would create the normal maps if you need them.

 

[bloodbob]

If you wanted a normal map from those images you'd have to draw it by hand. ( well you'd do a hightmap by hand ).

You really need a straight on shot to make a texture not a angle.

 

[mito]

Thanks bloodbob and soylent for your answers.

My intention is to create a texture based on a digital picture just like the ones above.

According to soylent, it's a question of making the right and perpendicular shots.

 

[bloodbob]

According to soylent, it's a question of making the right and perpendicular shots.

Yeap thats correct you want lighting from all directions as well.

 

[pegisys]

Nvidia made a photoshop plugin that will turn images or bumpmaps into normal maps, it's not perfect but it's better then doing it by hand

http://developer.nvidia.com/object/nv_texture_tools.html

a few other things that might come in handy there aswell

 

[Ostsol]

It's probably meant for heightmaps and as such will simply treat the darker areas on a textures as the lower points and the brighter areas as the higher points. It will be quite inaccurate.

 

[soylent]

Not only do you need good shots, you need to make it tile nicely. There's no magic bullet for this, but the clone tool in photoshop with a small soft brush is a good starting point. Use the offset 'filter' to bring in the 'seam' into the middle of the texture and work on it until you have a hard time seeing it anymore. These ought to have their equivalents in gimp.

Plan on using a power of two texture, i.e. 2^n pixels wide by 2^m pixels tall.

Like most things, making good textures is a patience and experience thing rather than a cookie cutter process.

 

[Xmas]

The shots don't need to be exactly perpendicular. If the surface is mostly flat you can do perspective reconstruction with four reference points IIRC. However, the more distortion, the more resolution is wasted. And you need to make sure the surface of interest doesn't exhibit much "height".

Also you want as few pre-baked lighting as possible while keeping vivid colors, so for outdoor photos that means neither direct sunlight nor shadows. The weather should be slightly cloudy but not dull when you take those photos.

 

[Simon F]

Not only do you need good shots, you need to make it tile nicely. There's no magic bullet for this....

Actually, there are a number of "magic bullets" for this.

Have a look at, say:

http://www.cc.gatech.edu/cpl/projects/graphcuttextures/

http://research.microsoft.com/~cohen/WangFinal.pdf

http://w3.impa.br/~lvelho/ip03/demos/conti/PI-fragcomp.pdf

ftp://ftp.research.microsoft.com/users/bainguo/sig03/sig03-PVT.pdf

http://portal.acm.org/citation.cfm?id=882269

 

[bloodbob]

I really wouldn't call wang tiles a magic bullet for most things as unless you have some common seams I think you would end up with alot of mirroring of tiles which I would think in some appiclation could look crappy. Anyway thats my opinon since I see alot of papers talking about using texture synthesis on the generation of tiles.

Umm on texture synthesis you might also wanna look at the hybrid texture synthesis here http://www.nealen.com/prof.htm and if you can obtain a copy of matlab ( through legal means of course ) there is a matlab implementation on the website too.

 

[Simon F]

I really wouldn't call wang tiles a magic bullet for most things as unless you have some common seams

But could you not use the graphcut texture technique to manufacture lots of tiles from the source image?

 

[bloodbob]

I really wouldn't call wang tiles a magic bullet for most things as unless you have some common seams

But could you not use the graphcut texture technique to manufacture lots of tiles from the source image?

Yes you can but in itself its a poor magic bullet.