4 ms·

I had a particularly hard time grokking the way the semilator works to reduce pattern size. It's a pretty difficult term to google too, being so similar to the

I had a particularly hard time grokking the way the semilator works to reduce pattern size. It's a pretty difficult term to google too, being so similar to the word 'simulator'. Does anyone well versed in GoL-ogy care to share a short ELI5? Edit: thanks you people for the explanation, makes sense. Nice hack to make it feasible.

biggiemac42 4y ago
Right, as far as I can tell the term "semilator" was coined for this task, so google won't help. The middle of the RCT pattern where all of the action happens, reads its first bit 2^N generations B.S (before singularity, or before splat, whichever you prefer). Next bit is 2^(N-1) B.S. Next would be 2^(N-2), but this is what the semilator changes. During the franky enormous gap between 2^(N-1) and 2^(N-2) generations B.S, extra spaceships come in at an orthogonal direction. These have two possible configurations, giving equivalent results to either of the possible bit reads. This accelerates the speed of bit reading, and means that N of millions can be emulated by a pattern with N less than 30. Much less initial distance, much less time. The addition of millions of cells of spaceships doesn't make the overall pattern smaller in an informational sense, just in the scale of time and distance between its constituent parts.
OscarCunningham 4y ago
So the full-size pattern works by bouncing a signal back-and-forth between the construction site and an oncoming GPSE. Each time it does this it produces either one or two gliders depending on the positioning of the GPSE. It is these gliders that do the construction. But the 'recipe' contains 1665791 bits, meaning the signal has to bounce back-and-forth 1665791 times. Because the distance to the GPSE halves every time, it would have to start at a distance of 2^1665791, which is impractically large. So instead we only have it bounce back-and-forth a small number of times (26), and insert the other 1665765 bits 'manually' by adding streams of 1665765 spaceships that collide near the construction site.

biggiemac42 4y ago

Right, as far as I can tell the term "semilator" was coined for this task, so google won't help. The middle of the RCT pattern where all of the action happens, reads its first bit 2^N generations B.S (before singularity, or before splat, whichever you prefer). Next bit is 2^(N-1) B.S. Next would be 2^(N-2), but this is what the semilator changes. During the franky enormous gap between 2^(N-1) and 2^(N-2) generations B.S, extra spaceships come in at an orthogonal direction. These have two possible configurations, giving equivalent results to either of the possible bit reads. This accelerates the speed of bit reading, and means that N of millions can be emulated by a pattern with N less than 30. Much less initial distance, much less time. The addition of millions of cells of spaceships doesn't make the overall pattern smaller in an informational sense, just in the scale of time and distance between its constituent parts.

OscarCunningham 4y ago

So the full-size pattern works by bouncing a signal back-and-forth between the construction site and an oncoming GPSE. Each time it does this it produces either one or two gliders depending on the positioning of the GPSE. It is these gliders that do the construction. But the 'recipe' contains 1665791 bits, meaning the signal has to bounce back-and-forth 1665791 times. Because the distance to the GPSE halves every time, it would have to start at a distance of 2^1665791, which is impractically large. So instead we only have it bounce back-and-forth a small number of times (26), and insert the other 1665765 bits 'manually' by adding streams of 1665765 spaceships that collide near the construction site.