Thread for your unsure discoveries

qqd · Post by **qqd** » June 9th, 2023, 3:47 am

From Re: Thread for you Useless Discoveries:

qqd wrote: ↑
June 8th, 2023, 2:01 pm
Game of Life Fun wrote: ↑
November 14th, 2022, 3:30 pm
Glider, block and LWSS collision and everyone survives:
Code: Select all
x = 17, y = 21, rule = B3/S23
7b2o$7b2o11$2o$b2o$o2$15bo$14b3o$13b2obo$13b3o$14b2o!
...
I just realized that the glider is delayed by exactly 1 tick in the above reaction. This gave me an idea of making a 1-tick glider delayer, which could be useful for controlling glider timings very precisely. The general mechanism is displayed below (using xWSSes to avoid clearance issues):
Code: Select all
x = 28, y = 102, rule = B3/S23
5b2o$5b3o$4bob2o$4b3o$5bo4$5bobo$8bo$8bo$5bo2bo$6b3o5$8bobo$11bo$7bo3b
o$11bo$8bo2bo$9b3o27$21bo$21b3o$24bo$23b2o5$2b2o$3bo14b2o$3o15b2o$o10$
11b3o$13bo$12bo2$25b3o$24bo2bo$27bo$27bo$24bobo10$11b3o$11bo2bo$11bo$
11bo3bo$11bo$12bobo4$8b3o$8bo2bo$8bo$8bo$9bobo!
When the glider is present, as shown above, your reaction produces a 1-tick delayed glider, moving the block in the process. Then the LWSS participating in the reaction gets destroyed by an eater 1, and 4 of the remaining xWSSes restore the block to its original position. The remaining LWSS is destroyed by another eater 1, and its purpose is to clean up the reaction if the glider is absent:
Code: Select all
x = 28, y = 102, rule = B3/S23
5b2o$5b3o$4bob2o$4b3o$5bo4$5bobo$8bo$8bo$5bo2bo$6b3o5$8bobo$11bo$7bo3b
o$11bo$8bo2bo$9b3o27$21bo$21b3o$24bo$23b2o5$2b2o$3bo14b2o$3o15b2o$o10$
11b2o$13bo$12bo2$25b3o$24bo2bo$27bo$27bo$24bobo10$11b3o$11bo2bo$11bo$
11bo3bo$11bo$12bobo4$8b3o$8bo2bo$8bo$8bo$9bobo!
On their own, the 4 xWSSes that restore the block when the glider moves it in the previous reaction, now just create a single blinker (they also react with the block but leave it unaffected). The final LWSS cleans up this blinker. Overall, this mechanism will only work with periods that are multiple of 2 (because of the blinker), but what does it matter when you can adjust glider timings to anything at all. Just put some guns (of any period of your choosing) to fire these 6 xWSSes at the reaction site, and you're done. (This is why we use xWSSes instead of gliders, as guns tend to be much closer to the reaction site, probably not giving enough room for the input glider to enter.)

Long story short, this reaction is definitely not completely useless.

Could this be completed? I have no idea where to place the guns to complete this 1-tick glider delayer, though I know it is definitely possible.

Post by **dvgrn** » June 9th, 2023, 4:46 pm

qqd wrote: ↑
June 9th, 2023, 3:47 am
Could this be completed? I have no idea where to place the guns to complete this 1-tick glider delayer, though I know it is definitely possible.

I think we'd need a specific use case where this particular 1-tick delayer mechanism would be an improvement on every other 1-tick delayer that we already have available. Otherwise it's just a bit too complicated to synchronize all those glider and *WSS signals, just to do something that we can do without any synchronization.

When we want to delay a glider by one tick, we could either

1) build a one-time 0-degree 0-lane shifter on the glider lane, or
2) put a demultiplexer on the glider lane, just in front of a few Snarks that delay the glider a little bit. Route the deflected glider from the demultiplexer to a merge circuit that drops the glider back onto the same lane it would have been on otherwise, just one tick slower.

The second option gets used every now and again, in resettable guns and oscillators -- e.g., mersenne-82589933.mc.gz in Golly's Help > Online Archives > Computation ... Devices, which effectively speeds up a glider by one tick rather than slowing it down, but it would be easy to change it so that it added one to the period instead of subtracting one.

EDIT: On a second look, it seems a bit odd to use up so incredibly many *WSSes to do the block reset, when it's just a standard (2,1) block pull. Would something like this count as a completion?