bomb is automatic interactive visual stimulation.

bomb is a program that runs on a PC. it belongs to the vaguely defined class of graphics programs called `eye candy', or `screen savers', or `screen hacks'. it produces continually changing visual effects independently, or under keyboard control. bomb is work in progress: my ultimate goal is to create a visual musical instrument.

the implementation for OpenGL, linux, and PowerMac is available here, including a collection of screen shots.

the program has many modes, each of which may produce several (or many) effects. most of the effects are non-representational textures, harmonic geometry, and fractals. a library of scanned images and characters provides a visual iconic symbolic component to some of the modes. the icons function as lyrics.

the texture effects are produced with cellular automata (CA): the prime CA used is cooled diffusion with a mask and underflow. `diffusion' means that each pixel is (say) heat, and is averaged with its neighbors each frame. this creates the blurring and spreading. `underflow' means that when heat reaches -1, it goes to its maximum. this creates the chaotic boiling. `with a mask' means that a bitwise constant is chosen, and all heat values are ANDed with this constant. (persian rug from hopkins, mask from jepler).

this heat layer is then driven by various functions:

• underflow-enable is driven with a square wave
• another CA such as life, fredkin's rule, symmetric life, or an excitation-relaxation system (barking dogs/neurons/forest fire/BZ).
• another heat layer at a different time/space scale
• an image
• a trail of points from random-walk sinusoids produces the rotor (idea by tcl)
• a trail from a time-varying flame IFS
• a collection of fish or slugs (by nix)
• more complex things that distort the diffusion kernel as a fn of the driver, producing flow and fiber effects.
• symmetries (tiles and mirrors) are used both for visual effect and to make computing the driving function faster.

a separate mode implements reaction-diffusion textures. it has two reactants, four slightly different reactions, and a collection of different diffusion patterns:

• isotropic
• horizontal
• vertical
• square grid
• zig-zag
• image-picks horizontal/vertical
• radial
• circular
• gradient(image) rot by pi/2 (still experimental)

basically i've thrown together a menagerie of parameterized screen hacks (some of them contributed by others) with a zillion keyboard commands for tweeking the parameters and an automatic navigator that can set and adjust the parameters on its own (aleatoric). the fundamental kbd command is on the space bar: it picks a fresh random parameter set, killing the current set.