That wonky pipe screensaver in windows, I would like to create a similar effect in GEM, I'm low on imagination regarding how to go about this. Anyone got any ideas?

it's basically a 3D grid / cubic honeycomb, with a finite number of different things that can be in each cube, eg:

empty
pipe growing from bottom to top, or front to top with a bend (etc, there are 6 * 5 = 30 ways for the pipe to grow)
pipe from bottom to top (etc, there are 6 * 5 / 2 = 15 ways for the completed pipe to exist, as both ends are equal)

so that's 46 states for each cell, assuming there's only 1 colour of pipe

then you can have 1 variable which is %grown (assuming all pipes grow at the same speed), which cycles 0->100%, when it reaches 100% the cell changes state from growing to fixed and the next cell changes from empty to growing

you can probably figure out some cellular automaton rules for "growing pipes", maybe with some random element too, but you might get collisions - to avoid collisions you need some weird nonlocal algorithm probably

great info claudius, I'm on it now.