Graphics Reference
In-Depth Information
10
Noise
One of the perpetual challenges of computer graphics has been to create images
that are not only geometrically correct, but are also visually interesting. Texture
mapping of real images is commonly used in this way. Another technique
involves adding procedural “random” effects such as are seen in natural phe-
nomena (clouds, fire, smoke), natural materials (marble, wood, granite, sand),
small-scale randomness (random textures in materials), and many other things,
through the use of
noise
functions. In this chapter we discuss noise functions
and their use in shaders, specifically fragment shaders, in creating images.
The topic of noise is not necessarily associated with shaders, and you
may have encountered it in another computer graphics course. We describe it
separately from the details of shaders because it has interest on its own, and
we will certainly find that it adds very interesting opportunities for shaders to
use in creating some very atractive images.
213
