Rhombic wrote:I would like to know how you guess a way to extend a wick with certain properties.
That's a harder question to answer. It's not a matter of guessing so much as getting very familiar with the possibilities -- for example, what shapes of dying sparks you can get by crashing two or three gliders together, or by crashing a couple of gliders into a small still life? What can these dying sparks do if they're right next to (for example) one end of a barber pole?
So one way to get started in this case would be to manually draw small sparks next to the end of the barber-pole and observe the results. If you can find a small peturbation that makes part of the change you're looking for, you can look for a way to create that exact spark pattern by crashing gliders together.
Then go on and analyze the other cells in the neighborhood. If you get to where you're saying, "the whole thing would work if only
this cell were ON, or if
that cell were OFF, at tick number such-and-such," then maybe you can add another spark that will cause or suppress a birth in that particular cell at that generation, without affecting the rest of the reaction.
The way that births and suppressions work is very specific to the particular rule you're working with, of course, so what you learn in a project like this won't necessarily transfer very well to other Life-like CA rules.
Rhombic wrote:My guess is to use some puffers or glider guns to create a sort of ship that, while moving, creates the "top" of the barberpole.
I didn't find any kind of barberpole stretcher spaceship in my search, though people have talked about it, and it seems technically possible -- it could be a c/5 diagonal asymmetric ship, or a c/4 diagonal glide-reflecting ship, among other possibilities. Finding that would most likely require an extended
lifesrc/
WLS/
JLS search, but it's possible that computers have gotten enough faster in the last decade that something might turn up.
You might also look into whether it's possible to stretch a barberpole fast enough to make it 8 diagonal cells longer in 96 ticks, with glider collisions like the ones in the slide-gun pattern. If that can be done (which seems pretty unlikely, but I'm not thinking too hard about it) then it might be possible to design a barberpole-stretching flotilla of Cordership rakes.