Procedural Texture Generation
We often generate textures procedurally
• synthesis from example textures
• randomized material models (e.g., marble, wood, granite, …)
• reaction–diffusion “chemical reaction”
• any other function we can imagine
Closely related to procedural geometry synthesis
• and a lot of the techniques crossover
• see book by Ebert et al
Texturing & Modeling: A Procedural Approach
Randomized Models
Randomized procedural texture models are quite popular
• start with some regular pattern
• add in a bunch of noise functions, at different frequencies
– Perlin’s noise function is a particularly popular choice
– he won an Academy Award for developing it
• used for both 2-D and solid textures (hypertexture)
Cool demos
•http://graphics.lcs.mit.edu/~legakis/MarbleApplet/marbleapplet.html
•http://mrl.nyu.edu/perlin/demox/Planet.html
Reaction–Diffusion Methods
Imagine that we have some “chemicals” in the plane
• they diffuse across space
• and they react with each other
• according to differential equations we make up
This describes realistic animal patterns
• appears this may actually account
for real stripe/spot formation
Demos of reaction–diffusion
•http://members.aol.com/_ht_a/jiweichsel/wr3.html
•http://www.ccsf.caltech.edu/ismap/image.html
Generating Textures on Arbitrary Surfaces
Using Reaction-Diffusion
Greg Turk, SIGGRAPH 91.
Synthesizing Textures
How do we efficiently generate textures?
• a common approach is to photograph something real
• for example, photograph some brick & apply to our walls
• this is nice, but it’s limited — all walls have identical bricks
Solution #1: Take lots of different photos
• works, but requires lots of storage
Solution #2: Synthesize new brick textures
• start with an example of a given texture
• synthesize new textures which have similar overall look, but
whose local features are distinct
•http://www.cs.berkeley.edu/~efros/research/synthesis.html
•http://www.cc.gatech.edu/cpl/projects/graphcuttextures/