Scorbie wrote:1) I'm not sure if this should be considered as a p2 combo or a new rotor. The rotor is basically 2 copies of the spark coil, but the stators of the spark coil cannot be welded into sth like this.
Code: Select all
x = 10, y = 9, rule = B3/S23
b2o4bo$bobo2bobo$3bo2bo2bo$2bob2ob2o$2bob2obo$b2o4bo$o2bo2bo$bobo2bobo
$2bo4b2o!
It's two copies of the same rotor, but it's a novel bushing arrangement.
Still, I don't think these are newbie questions. A lot of Life enthusiants mainly focus on construction/engineering topics, not so much on classification and analysis. As I see it, an "oscillator combo" can mean many different things, e.g.
- Two well-separated oscillators.
- Two separate, non-interacting oscillators in a pseudo-still-life type arrangement.
- Two separate oscillators welded together by casing.
- Two non-contiguous rotors sharing the same bushing (but which could be also attached to a casing all by themselves).
- Two non-contiguous rotors sharing the same bushing, which could not be supported without the presence of at least two rotors.
- Two contiguous rotors that do not interact.
- Two rotors that can exist self-standing, but which are contiguous to some rotor cells that cannot.
The fifth type, which your p2 example falls under, already includes plenty of oscillators that are usually considered novel patterns in their own right; e.g. the
toaster, which has two copies of a lateral sparker rotor, plus a central rotor that is essentially a variant of
siesta.
For pattern classification, I believe there is some need for a term that would refer to a specific rotor/bushing arrangement, as this seems to be the most common point used to define "an" oscillator. E.g. a blinker and a bipole (which have the same rotor) are different oscillators in a way that bipole and bipole-tie-boat are not. All oscillator censuses that I have seen fail to make this distinction though, or even the type 2 / type 3 distinction, and count things like "two beacons on Z-heptomino" as a separate oscillator (or, indeed, as four different ones per cis/trans isomery):
Code: Select all
x = 11, y = 5, rule = B3/S23
4b2ob2o$2o3bobo$o4bo4bo$3bobo3b2o$2b2ob2o!
…which to me seems like missing the point.
An example of the 6th type (analogous to tie still lifes) would be this mold on mold arrangement:
Code: Select all
x = 9, y = 9, rule = B3/S23
3b3o$3b3obo$4bobobo$2o3bo2bo$3o3b2o$2obo$2bobo$bo2bo$2b2o!
The center sparks touch one another, but since they are only upgraded from 0 neighbors to 1 neighbor, this makes no difference for the evolution of the pattern.
Scorbie wrote:2) I feel uneasy with the term 'true oscilator' because it includes things like
caterer on figure eight which doesn't seem original at all...
A relevant concept for these could be the "engine period". An
engine (or, perhaps, a "minimal engine" — I am still developing this terminology and it is still somewhat in flux) is a set of (rotor) cells in a period-
n pattern that is a complete set of
nth parents of itself, and does not contain a smaller engine within itself. Oscillators like caterer on figure eight are what I'd call "
spark-coupled": they contain higher-period cells, but they do not contain any higher-period engine.
Note that engines are not necessarily self-sufficient, since they're only defined in terms of birth and not death. E.g. the two halves of
tumbler are both engines in their own right, and the
pentant's engine excludes the eater. (The eater itself is not an engine; it's more of a hassled object. I suppose it is possible to define as "output" any rotor segment that is not part of an engine; this then divides into sparks, hassled objects, and probably some other subtypes.)
