Previous:Boxed Main Index Next:Brick
The bozo
pattern is a very smooth, random noise function that is traditionally used with some turbulence to create clouds. The spotted
pattern is identical to bozo
but in early versions of POV-Ray spotted did not allow turbulence to be added. Turbulence can now be added to any pattern so these are redundant but both are retained for backwards compatibility. The bumps
pattern is also identical to bozo
when used anywhere except in a normal
statement. When used as a normal pattern, bumps
uses a slightly different method to perturb the normal with a similar noise function.
The bozo
noise function has the following properties:
1. It's defined over 3D space i.e., it takes x, y, and z and returns the noise value there.
2. If two points are far apart, the noise values at those points are relatively random.
3. If two points are close together, the noise values at those points are close to each other.
You can visualize this as having a large room and a thermometer that ranges from 0.0 to 1.0. Each point in the room has a temperature. Points that are far apart have relatively random temperatures. Points that are close together have close temperatures. The temperature changes smoothly but randomly as we move through the room.
Now let's place an object into this room along with an artist. The artist measures the temperature at each point on the object and paints that point a different color depending on the temperature. What do we get? A POV-Ray bozo texture!
Previous:Boxed Main Index Next:Brick