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The documentation on the RLE format states that values for many-state rules should start with '.' for 0, 'A' for 1, and go up to 'X' for 24. Then they count up from 'pA' for 25 to 'pX' for 48, 'qA'=49, 'qZ'=72. Wait, 'qZ'? If it gets to Z, it would have to be state 74. And this is incongruent with what golly produces: "qWqXrArB". There is no 'qY' or 'qZ'. That's a simple typo though, I'm more interested in knowing why it only counts up to X instead of Z in the first place. That seems pointless; you're just wasting two good letters (not that we don't already have more than enough combinations for all the states), and why start at 'p'?

blah wrote:There is no 'qY' or 'qZ'. That's a simple typo though.

True, thanks for reporting. I've fixed it in the Golly docs.

blah wrote:I'm more interested in knowing why it only counts up to X instead of Z in the first place. That seems pointless; you're just wasting two good letters (not that we don't already have more than enough combinations for all the states), and why start at 'p'?

Was looking at that recently. I don't have an answer on the decision to start with 'p' instead of 'a' as the old MCell multi-state RLE format does... except that it prevents 'b' or 'o' from being used, which might make it easier for Golly to guess correctly what format a random chunk of text might be in. (Technically you don't get to 'o' if you start with 'a' anyway, though.) MCell had an "#L" prefix to make things pretty clear, but Golly has to work with just the encoding itself.

As far as skipping 'Y' and 'Z', well, MCell format does the same thing for whatever reason. Maybe having the base be a multiple of 8 just looked a little cleaner somehow. A 16-letter subset could have been a contender, but I suppose that would have been just a weird nonstandard hexadecimal.

And when I paste an RLE into Golly from Lifewiki, I get an empty rectangle! Please change it back!

wwei23 wrote:And when I paste an RLE into Golly from Lifewiki, I get an empty rectangle! Please change it back!

What RLE? It's far more likely you got something wrong.

Golly's RLE parser has not changed, only the documentation. Please post the broken RLE here and a link to where you got it.

There's a space after the rule is stated and it confuses Golly.