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 Sat, Jul 18, 2020 04:54 AM UTC in reply to Fergus Duniho from 04:54 AM:

No, you can add a new piece to an empty square, but that would not be called promotion.

I meant: would it be possible to clear a piece from an occupied square by 'free-dropping' an empty square on top of it (e.g. by entering @-f1). And come to think of it: the code that checked the promotion just looks whether the piece at 'dest' after the move is still 'moved'. But what if someone would have really entered the typo R a1-f1; Q-a1; ? Presumably that would leave a Rook at f1, so you would not catch that. Would it have free-dropped a Queen at a1 after the Rook moved ('fertile Rook')? Or is there some intrinsic test on the input that enforces that promotion moves can only free-drop on dest? (Probably not, because that would make the mention of any square redundant.) Because the promotion move doesn't set any variable similar to dest, it isn't clear to me how you could test whether free-drops go to an allowed square.

BTW, some variants allow only promotion of a piece that was lost before, and in those it can make sense to collect the captured pieces in a separate area (without color flip), and move them from there to effect promotion.

I have never programmed Chu Shogi, and I'm not sure what a locust move is.

'Locust capture' in general is capturing a piece on a square you are not moving to. Like capture in Checkers, or e.p. capture in orthodox Chess. But in these two cases the capture is an implicit side effect of the move. So the Pawn subroutine can recognize e.p. capture, and automatically remove the victim, without the user having to enter any additional moves. (I guess promotion in Shatranj or Makruk could also be handled that way.) The problem arises when the capture would be optional. E.g. in Odin's Rune Chess a Forest Ox moves and captures like a Knight, but can in addition remove one other enemy piece adjacent to its destination. So there you would somehow have to indicate whether you want to do that, and if so, which of the (possibly eight) adjacent pieces. F c3-e4; @-d5; could be a suitable notation for that, if such a thing were allowed.


Edit Form

Comment on the page Play-test applet for chess variants

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.