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 is 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!
The bozo pattern has a default color_map built in that results in a green, blue, red and white pattern
with sharp transitions.
Note: The appearance of the bozo pattern depends on the noise_generator used. The
default type is 2. This may be changed using the noise_generator keyword (See section "Pattern
Modifiers / Noise_generator").
More about "Noise_generator"
|