Surfacing - Blender Foundations: The Essential Guide to Learning Blender 2.6 - page 168

and procedural. Image textures use image
files to create their variation. Figure 7.3
shows a digital photo of a section of
carpet. A little later, we'll use that image
to vary the material properties of the floor
so that our 3D surface looks like carpet.
The other type of texturing, procedural,
is generated on-the-fly from mathemati-
cal models within the renderer. Blender
has a decent number of procedural textur-
ing styles (wood, marble, clouds, and
noise are a few) that more or less don't
look like what you'd hope.

I'm going to catch some grief for this,
but I find procedural textures of limited
value. Not necessarily zero value, but
there you have it. It is so simple now to
just grab your digital camera and start
snapping, or to browse www.lickr.com for
Creative Commons material for use as textures in your scenes, that the difficulty involved in creating a
good procedural is just not worth it.

Figure 7.3 This is carpet.

With that said though, let's start by using a procedural texture to roughen the walls and learn the ropes.

Every surface you can observe around you shows variation in at least three properties: color, shine, and
roughness. Even a white painted gypsum wall varies, although that variation is extremely subtle. The color
of a wall will probably vary near the floor, in corners, and near any openings, where dirt will tend to
accumulate. The shine will vary in a similar way, as dirt reduces the sheen of the paint, but it might also
increase in certain places if people have leaned against it, leaving a slight oily handprint or shoulder print.
The roughness on such a wall shows up as micropits, or in the case of a highly textured drywall job, as
peaks and valleys of drywall compound.

If at this point you're thinking, “Gee, I have to think about this kind of stuff for every object in my
scene?” rest assured. The truth is that you don't have to think about it that hard, if you want your work
to be lame. However, if your goal is to make your scenes feel like real places, even if they are stylized
and nonphotorealistic, you have to give the viewer the subtle clues that they need in order to believe. So
yes, you have to think like this for your “hero” objects. Stuff that's way in the background or that flies
on and off camera in the blink of an eye can do with a little less attention, as we'll see later. But for the
main things, don't compromise.

And with that note about details being important, we're going to skip the dirt and handprints for now, as
they require skills that you don't have yet. Let's examine Figure 7.4 , which shows the Texture context of
a Properties window.