Pavgran wrote: ↑January 27th, 2020, 4:26 am

Why some cases of non-interacting spaceships are combined into one "spaceship"?

For example,

here there are cases where the distance between spaceships is always at least 2 squares.

This happens in a

*lot* of rules, and you can find many examples in earlier pages of this thread, also with oscillators. Usually these are pairs of spaceships where, over the course of one full period, their envelopes will at least slightly overlap. The reason they are combined together likely has to do with apgsearch being coded in such a way that RROs with multiplicity would be detected with the multiplicity, even if the RRO copies do not react on an individual level. Because it's difficult to distinguish such "interesting" combinations from trivial ones algorithmically, I suspect apgoucher/calcyman just had the algorithm err on the side of inclusivity (combine-ity) for the sake of not missing RROs.

Interesting... here is the soup in question.

Code: Select all

```
x = 16, y = 16, rule = B3-n45qr6i/S2eik3
ob4ob2ob4o$b3o3bobo2bobo$obo2b4obob2o$2b3o3b2obob2o$4obobob3o2b2o$ob3o
2bo3b5o$3o3bobob2o2b2o$5b2obob3o2bo$ob3ob3o2b2o2bo$4obo3bobo2b2o$bo2b
4obobob3o$o2bobobo5bo$3o3b2o2bobobo$obob2obo2b2obobo$o2bo2bob2ob2o2bo$
4o2bo3b4obo!
```

I expect the misidentification comes from generation 57, where the spaceship does briefly appear... only for debris behind it to destroy it. Apgsearch must be missing that the spaceship is destroyed by debris, which may be to do with the fact the debris appears behind the ship and not in front of it, so the algorithm may be automatically assuming the spaceship gets away because there's nothing in front of it. This seems like a genuine, novel bug, interesting.