1. Create Procedural Textures with Perlin Noises
Wei Shen
CMPS 260

2. Perlin Noise Noise Function – A seeded random number generator
Interpolation Function – Linear Interpolation, Cosine Interpolation, Cubic Interpolation, etc.

3. Frequency = 1/Wavelength
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

9. Random Number Generator
Example:
function IntNoise(32-bit integer: x)
x = (x<<13) ^ x;
return (1.0-((x*(x*x* ) )&7fffffff)/ );
end IntNoise function

10. Interpolations Linear Interpolation:
function Linear_Interpolate(a, b, x)
return a*(1-x) + b*x
end of function

11. Cosine Interpolation:
function Cosine_Interpolate(a, b, x)
ft = x *
f = (1 - cos(ft)) * .5
return a*(1-f) + b*f
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:
Procedure Textures:
Ken Perlin’s Homepage: