Create Procedural Textures with Perlin Noises

1
Create Procedural Textures with Perlin Noises
Wei Shenweishen_at_cse.ucsc.edu
CMPS 260
2
Perlin Noise

• Noise Function A seeded random number generator

• Interpolation Function Linear Interpolation,
  Cosine Interpolation, Cubic Interpolation, etc.

3
Wave Properties

Frequency 1/Wavelength
4
Noise Functions

5
Add them together, then
6
Some noise functions created in 2D
Adding all these functions together produces a
noisy pattern



7
Persistence

• A single number used to specify the amplitude of
  each frequency
• Frequency 2i
• Amplitude Persistencei
• i is the ith noise function being added
• Octave each successive noise function

8
(No Transcript)
9
Random Number Generator
Random Number Generator
Example function IntNoise(32-bit integer x)
x (xltlt13) x return
(1.0-((x(xx15731789221)1376312589)7fffffff)/
1073741824.0) end IntNoise function
10
Interpolations

• Linear Interpolation

function Linear_Interpolate(a, b, x) return
a(1-x) bx end of function

11

• Cosine Interpolation

function Cosine_Interpolate(a, b, x) ft x
3.1415927 f (1 - cos(ft)) .5
return a(1-f) bf end of function

12

• Cubic Interpolation

function Cubic_Interpolate(v0, v1, v2, v3,x)
P (v3 - v2) - (v0 - v1) Q (v0 - v1) - P
R v2 - v0 S v1 return Px3
Qx2 Rx S end of function


13
Smoothed Noise



14
Applications of Perlin Noise

• 1-Dimensional controlling virtual beings,
  drawing sketched lines.

15

• 2-Dimensional landscapes, clouds, generating
  textures.
• 3-Dimensional 3D clouds, animated clouds, solid
  textures.
• 4-Dimensional animated 3D textures and clouds.

16
3 Dimensional Perlin Noise, 4 Octaves,
Persistence 0.25 and 0.5
Low persistence


Mix two Perlin Functions
Bumps - high frequency noise stretched in one
dimension
17
References

• Perlin Noise http//developer.intel.com/drg/mmx/a
  ppnotes/proctex.htm
• Procedure Textures http//developer.intel.com/drg
  /mmx/appnotes/proctex.htm
• Ken Perlins Homepage http//mrl.nyu.edu/perlin/