Texture Basics...

[Ross Macintosh]

For the group effort to create a little Robot I offered to create some textures. Now I must ask what are the properties of a good texture? I thought some discussion on this might help me with my task at hand, but could also be useful to the modelers. Sometimes addressing the basics even helps the experts...

Is there an optimal size?
How important are tiling textures?
Are jpg's okay?
Are transparent png's useful?
If a tree falls in the forest do modelers care?
Do you use greyscale textures as bump maps to add 'texture' to other textures?
Are different resolutions of the same texture useful?

Those are just a few questions that come to mind. I suppose the real question is: what are the characteristics of a good texture? Tell me and I'll make some! (Words of a enthusiastic simpleton who doesn't know better [img]/infopop/emoticons/icon_wink.gif[/img] ).

Regards, Ross

<a href=http://www.designstop.com/>DesignStop.Com</a>

[Ross Macintosh]

For the group effort to create a little Robot I offered to create some textures. Now I must ask what are the properties of a good texture? I thought some discussion on this might help me with my task at hand, but could also be useful to the modelers. Sometimes addressing the basics even helps the experts...

Is there an optimal size?
How important are tiling textures?
Are jpg's okay?
Are transparent png's useful?
If a tree falls in the forest do modelers care?
Do you use greyscale textures as bump maps to add 'texture' to other textures?
Are different resolutions of the same texture useful?

Those are just a few questions that come to mind. I suppose the real question is: what are the characteristics of a good texture? Tell me and I'll make some! (Words of a enthusiastic simpleton who doesn't know better [img]/infopop/emoticons/icon_wink.gif[/img] ).

Regards, Ross

<a href=http://www.designstop.com/>DesignStop.Com</a>

[randyrives]

How about it expert texture maker's. Some of these questions have being banging around in my head.

One note I do use grey scale images to add bump and diffuse maps to my textures.


--Randy

[s.winders]

Is there an optimal size?,I usually use about 400x400 pixels,larger if I want more detail.

How important are tiling textures?,pretty important depending on what you are creating,for instance if you are making roof tiles or bricks then very important,but if it is a robot then probably a metal type texture with dirty parts here and there,depending on what everyone wants.

Are jpg's okay?,I usually use tifs,but jpegs should be alright also.
Are transparent png's useful?,not sure there.

If a tree falls in the forest do modelers care?,yes especially if it lands on me or some part of my anatomy.


Do you use greyscale textures as bump maps to add 'texture' to other textures?,yes most bumps are greyscale.

Are different resolutions of the same texture useful?,yes depending on the amount of detail you want.


Ok question time guys...how detailed do we want our robot?,do we want the robot old and grimy looking,or brand spanking new?,how techy do we want the texures to be or not be?
[img]/infopop/emoticons/icon_smile.gif[/img]


Cheers

Stu.

[Earl]

Hi Ross,

Ok..well, personally I enjoy using high res textures for most surfaces. That way I avoid situations where I want to do a close up and all of a sudden I realize my texture is inadequate for that res. For large scenes, you really must think ahead and plan, because a scene with hundreds of complex objects can get quite memory intensive fast. Here's an example straight from the LightWave manual on texture memory:
512x512 pixel eight-bit grayscale image:
Base image: 262,144 bytes (512 x 512 x 1)
First mipmap: 65,536 bytes (256 x 256 x 1)
Second mipmap: 16,384 bytes (128 x 128 x 1)
Total Memory used: 344,064 bytes
So the point is, memory gets filled up quickly. So for really large scenes, a machine with less than a GB of RAM could easily be brought to its knees. But for our robot experience, I don't see anything wrong with using high res textures (1024x1024). After all - we'll probably want a close up or two. =)

For color textures, 24-bit is ideal - unless it's one of those situations where all the colors are similar and you can get away with an 8-bit or less image. JPG compression is fine, as long as it isn't noticeably compressed (even when zoomed in). Nothing looks worse than JPG artifacts in a texture.

Tiling textures can be a lot of hassle. So I don't worry about it unless I know specifically that I want it tiling. Saves time. If it doesn't tile, it has to fit the whole surface one for one (such as, say, a texture for someone's face).

32-bit PNGs really aren't useful... at least the way LightWave uses textures. If I want to apply an alpha channel to a texture (which I often do), then I'll load the alpha channel seperately, so I can tweak it independently of the texture that's being alpha'd. One thing to note though: All alpha channels really should be 8-bit grayscale. Using a 24-bit color image as an alpha is a huge waste of memory (unless you already have that image loaded in memory, using the color values elsewhere). So nah, 32-bit PNGs aren't really useful. I almost exclusively use JPGs (with compression turned all the way down, to preserve the image).

It couldn't hurt to have different resolutions of the same texture, but I wouldn't use them all at the same time on the same object. It would be a huge waste of memory. I'd only use one at a time, and use that same one for all 'instances' of the texture/surface.

I'll see if I can't get more time later to think about other texturing type stuff.

[This message was edited by Earl Wilson IV on September 16, 2001 at 17:50.]

[Mark (theKeeper)]

...but i'll reIterate a few things. [img]/infopop/emoticons/icon_biggrin.gif[/img]

The larger the texture, the more details you can fit on it, which makes it more 'high-res' - it's a simple concept there.

Transparent PNG images aren't really needed nowadays. A lot of the newer 3D apps can suck a bump, diffuse, & distortion map from the original source image. Some other uses for transparency is to create oddly or complex shaped objects - but by using only a simple primary shape. That's a tad out of our range here at the moment though.

I wouldn't use JPGs for textures if i had a choice. Use either a Tiff or a PNG or even a 24bit BMP. I generally use Tiffs because i can embed a mask channel into it if i need transparency for that texture; or a simple edge bump map.

If you're at all concerned about running out of Ram due to high-res textures, then create low-res versions to use for general referrence while creating the scene/models. Just make the textures very small in pixel dimensions.

My usual procedure will often see me working with low polygon models and low-res textures while i create the bulk of the models and the overall scene. Then when i'm at a more completed stage, i'll subdivide the models so they have more detail, and apply high-res versions of the textures. I do this usually just before a final Render.

Anywho... thought i'd speak up here also. [img]/infopop/emoticons/icon_biggrin.gif[/img]

[Gary David Bouton]

People--

I do not want to get into the texture discussion...on purpose. I'll add that a high-rez texture would be best, because you can alway render a low rez-model with a high rez texture and the only bad result is wasted clock cycles on your box.

I want this to be OUR statement in this forum, so please work with a little alacrity, but DO has it out so the collaborative effort is truly the best of all our hands and minds.


My Best,

Gary David Bouton
Gary@GaryDavidBouton.com
Free education! The Writings Web site
and the updated GaryWorld Gallery is pretty okay, too.