Self-Constructing Spaceship Challenges
Posted: October 31st, 2018, 4:05 pm
With the appearance of slmake/slsparse, self-constructing spaceships are getting so common that maybe they don't each need their own topic any more. Maybe just toss any new ones into this thread for a while?
Not Another Geminoid, For A Change
Here's a new kind of self-constructing spaceship. Right now it moves 2000260c/40007022, so just about c/20. The memory loop could be made a good bit smaller, which would get the loopship moving quite close to c/12.
An update was made to slmake/slsparse just a couple of days ago, that allows structures to be constructed directly along the construction-arm lane. This made it relatively trivial to compile this spaceship, with the help also of simeks' GoL-destroy search program. Details in some future post if anyone is interested.
Definition
A "loopship" is a self-constructing spaceship that contains a construction recipe to build a memory loop big enough to hold that same construction recipe. The Geminis, Demonoids, or Orthogonoids all just reflect a recipe back and forth between two universal constructors. Now we want to "catch and release" the recipe instead.
In other words, a loopship's construction recipe specifies the size of the memory loop, whereas in the various Geminoids the distance between the twin universal constructors is completely independent of the recipe.
Building a complete memory loop allows for a lot more flexibility in the design. Among other things, we can finally get away from the Huge Boringly Long Straight Line series of spaceships (and linear propagator).
Calcyman's 0E0P self-constructing metacell is the first example of a loopship, or at least it would be if a single cell was programmed to simulate some appropriate MAP rule such as
But as you'll see, this much more minimalist p40007022 loopship is likely to run a good bit better in Golly, at least for the foreseeable future.
Challenges, with associated arbitrary point assignments:
I won't actually promise anything, but these points may eventually be redeemable for LifeCAsh, if there ever is such a thing, after I decide what the point-to-LifeCAsh exchange rate will be.
Not Another Geminoid, For A Change
Here's a new kind of self-constructing spaceship. Right now it moves 2000260c/40007022, so just about c/20. The memory loop could be made a good bit smaller, which would get the loopship moving quite close to c/12.
An update was made to slmake/slsparse just a couple of days ago, that allows structures to be constructed directly along the construction-arm lane. This made it relatively trivial to compile this spaceship, with the help also of simeks' GoL-destroy search program. Details in some future post if anyone is interested.
Definition
A "loopship" is a self-constructing spaceship that contains a construction recipe to build a memory loop big enough to hold that same construction recipe. The Geminis, Demonoids, or Orthogonoids all just reflect a recipe back and forth between two universal constructors. Now we want to "catch and release" the recipe instead.
In other words, a loopship's construction recipe specifies the size of the memory loop, whereas in the various Geminoids the distance between the twin universal constructors is completely independent of the recipe.
Building a complete memory loop allows for a lot more flexibility in the design. Among other things, we can finally get away from the Huge Boringly Long Straight Line series of spaceships (and linear propagator).
Calcyman's 0E0P self-constructing metacell is the first example of a loopship, or at least it would be if a single cell was programmed to simulate some appropriate MAP rule such as
Code: Select all
x = 1, y = 1, rule = MAPIAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
o!
Challenges, with associated arbitrary point assignments:
- 3 points: first posted modification of attached loopship with a smaller period than 40007022.
- 1 point each: "place" and "show" -- second and third smaller-period loopships, provided that each one is smaller than the previous one, and the three loopships are posted by three different people
- 5 points: smallest period/fastest/lightest-weight loopship as of October 31, 2019 (yes, a year from now). If two loopships are the same period, the one with the fastest speed wins. If two loopships have the same period and speed, the one with the smallest minimum repeating population wins.
- 10 points: first posted HashLife-friendly loopship, with displacement and period both powers of two.
- 20 points: first posted oblique loopship (no glide-reflection shortcuts!)
I won't actually promise anything, but these points may eventually be redeemable for LifeCAsh, if there ever is such a thing, after I decide what the point-to-LifeCAsh exchange rate will be.