Check out Janggi (Korean Chess), our featured variant for December, 2024.

Enter Your Reply

The Comment You're Replying To
H. G. Muller wrote on Mon, Apr 22, 2019 08:13 AM UTC:

Actually, you can't count on that.  A pawn may promote to any piece from either army.

O sh*t, I hadn't thought of that. Probably because it cannot happen in Fairy-Max.  I still wouldn't be unhappy with the dressed-letter approach, though. Charging R and N could be R' and N', Bede could be B'. To me that doesn't look any worse than CN, RN and Bd. For the classical armies this would give: NBRQ, WFB'A, F'N'R'C, W'HSM. In almost any situation the punctuation would be irrelevant, as you would virtually never promote to Waffle, Fibnif, Woody Rook etc. So if we choose to use conventional disambiguation in SAN rather than punctuation, it would never virtually never need to disambiguate anything. And if the FEN is considered just an arbitrary string for computer consumption, it becomes irrelevant how it is done there anyway.

I use an underscore as a prefix to force recognition of two-letter notations.

I did something similar for the internal representation of start positions in my engine HaChu, using colon instead of underscore, but I wasn't very happy with the result. If auxilary symbols are used, you might as well just require all pieces to be separated by commas. (This is the notation that is also used in the TSA rule books for the various Shogi variants.) Forsyth notation was originally conceived for human reading, in newspapers. For computers it would be much more convenient to have some fixed-length format. You either don't care much about the length, (like in GUI-engine communication), or you care so much (in database applications) that FEN is hopelessly inefficient size-wise.

My problem has always been that XBoard would have to be changed in uncountable places to support even just 2-letter IDs. Which makes me inclined to consider options that objectively might not be the best. With the dressed letters the Id currently still fits in a byte, and only on reading or writing a mapping has to take place of the ASCII range 64-128 on the three other available 64-bit ranges. If I would manage to change all variables ever used to hold piece IDs to ints, I could use a similar strategy in storing mult-letter IDs e.g. as firstLetter + 256*secondLetter + ...


Edit Form
Conduct Guidelines
This is a Chess variants website, not a general forum.
Please limit your comments to Chess variants or the operation of this site.
Keep this website a safe space for Chess variant hobbyists of all stripes.
Because we want people to feel comfortable here no matter what their political or religious beliefs might be, we ask you to avoid discussing politics, religion, or other controversial subjects here. No matter how passionately you feel about any of these subjects, just take it someplace else.
Avoid Inflammatory Comments
If you are feeling anger, keep it to yourself until you calm down. Avoid insulting, blaming, or attacking someone you are angry with. Focus criticisms on ideas rather than people, and understand that criticisms of your ideas are not personal attacks and do not justify an inflammatory response.
Quick Markdown Guide

By default, new comments may be entered as Markdown, simple markup syntax designed to be readable and not look like markup. Comments stored as Markdown will be converted to HTML by Parsedown before displaying them. This follows the Github Flavored Markdown Spec with support for Markdown Extra. For a good overview of Markdown in general, check out the Markdown Guide. Here is a quick comparison of some commonly used Markdown with the rendered result:

Top level header: <H1>

Block quote

Second paragraph in block quote

First Paragraph of response. Italics, bold, and bold italics.

Second Paragraph after blank line. Here is some HTML code mixed in with the Markdown, and here is the same <U>HTML code</U> enclosed by backticks.

Secondary Header: <H2>

  • Unordered list item
  • Second unordered list item
  • New unordered list
    • Nested list item

Third Level header <H3>

  1. An ordered list item.
  2. A second ordered list item with the same number.
  3. A third ordered list item.
Here is some preformatted text.
  This line begins with some indentation.
    This begins with even more indentation.
And this line has no indentation.

Alt text for a graphic image

A definition list
A list of terms, each with one or more definitions following it.
An HTML construct using the tags <DL>, <DT> and <DD>.
A term
Its definition after a colon.
A second definition.
A third definition.
Another term following a blank line
The definition of that term.