Re: Proposal to add standardized variation sequences for chess notation

Michael Everson <everson_at_evertype.com>:
>
> Variation Sequences have been implemented for a number of symbol characters
> recently to make them useful for specialized purposes.

This is were I still suspected there was an April Fools joke coming up.

> Here is a proposal which solves a long-standing problem for an important set
> of symbols in the UCS.

    # Chesspiece on white versus Chesspiece on black variation sequences
    25A1 FE00; White chessboard square; # WHITE SQUARE
    25A8 FE01; Black chessboard square; # SQUARE WITH UPPER RIGHT TO LOWER LEFT
FILL
    2654 FE00; Chesspiece on white; # WHITE CHESS KING
    2654 FE01; Chesspiece on black; # WHITE CHESS KING
    2655 FE00; Chesspiece on white; # WHITE CHESS QUEEN
    2655 FE01; Chesspiece on black; # WHITE CHESS QUEEN
    2656 FE00; Chesspiece on white; # WHITE CHESS ROOK
    2656 FE01; Chesspiece on black; # WHITE CHESS ROOK
    2657 FE00; Chesspiece on white; # WHITE CHESS BISHOP
    2657 FE01; Chesspiece on black; # WHITE CHESS BISHOP
    2658 FE00; Chesspiece on white; # WHITE CHESS KNIGHT
    2658 FE01; Chesspiece on black; # WHITE CHESS KNIGHT
    2659 FE00; Chesspiece on white; # WHITE CHESS PAWN
    2659 FE01; Chesspiece on black; # WHITE CHESS PAWN
    265A FE00; Chesspiece on white; # BLACK CHESS KING
    265A FE01; Chesspiece on black; # BLACK CHESS KING
    265B FE00; Chesspiece on white; # BLACK CHESS QUEEN
    265B FE01; Chesspiece on black; # BLACK CHESS QUEEN
    265C FE00; Chesspiece on white; # BLACK CHESS ROOK
    265C FE01; Chesspiece on black; # BLACK CHESS ROOK
    265D FE00; Chesspiece on white; # BLACK CHESS BISHOP
    265D FE01; Chesspiece on black; # BLACK CHESS BISHOP
    265E FE00; Chesspiece on white; # BLACK CHESS KNIGHT
    265E FE01; Chesspiece on black; # BLACK CHESS KNIGHT
    265F FE00; Chesspiece on white; # BLACK CHESS PAWN
    265F FE01; Chesspiece on black; # BLACK CHESS PAWN
    26C0 FE00; Draughts piece on white; # WHITE DRAUGHTS MAN
    26C0 FE01; Draughts piece on black; # WHITE DRAUGHTS MAN
    26C1 FE00; Draughts piece on white; # WHITE DRAUGHTS KING
    26C1 FE01; Draughts piece on black; # WHITE DRAUGHTS KING
    26C2 FE00; Draughts piece on white; # BLACK DRAUGHTS MAN
    26C2 FE01; Draughts piece on black; # BLACK DRAUGHTS MAN
    26C3 FE00; Draughts piece on white; # BLACK DRAUGHTS KING
    26C3 FE01; Draughts piece on black; # BLACK DRAUGHTS KING

□ U+25A1 and, especially, ▨ U+25A8 for empty fields on a board make no sense.
U+25A8 always shows as diagonals from the lower left to the upper right (much
like a forward slash /). Black fields are often hatched this way, but could also
be shown with a solid fill ■ U+25A0, a reverse diagonal fill ▧ U+25A7, a diamond
pattern (diagonal crosshatch) ▩ U+25A9, a square pattern (orthogonal crosshatch)
▦ U+25A6, a vertical pattern ▥ U+25A5 or a horizontal pattern ▤ U+25A4. I
suggest you adopt a space character instead, e.g. U+2003 Em Space or U+2001 Em
Quad.

    2003 FE00; White chessboard square; # EM SPACE
    2003 FE01; Black chessboard square; # EM SPACE

    2001 FE00; White chessboard square; # EM QUAD
    2001 FE01; Black chessboard square; # EM QUAD

□ U+25A1, ▢ U+25A2 or ⬚ U+2B1A would also work if you wanted a minimal amount of
ink but not none.

    25A1 FE00; White chessboard square; # WHITE SQUARE
    25A1 FE01; Black chessboard square; # WHITE SQUARE

    25A2 FE00; White chessboard square; # WHITE SQUARE WITH ROUNDED CORNERS
    25A2 FE01; Black chessboard square; # WHITE SQUARE WITH ROUNDED CORNERS

    2B1A FE00; White chessboard square; # DOTTED SQUARE
    2B1A FE01; Black chessboard square; # DOTTED SQUARE

You should also evaluate a different approach altogether:

    20DE FE00; Combining white chessboard square; # COMBINING ENCLOSING SQUARE
    20DE FE01; Combining black chessboard square; # COMBINING ENCLOSING SQUARE

    20DE FE00; Combining white background; # COMBINING ENCLOSING SQUARE
    20DE FE01; Combining black background; # COMBINING ENCLOSING SQUARE

Although one would need to combine it with a space character as a base for empty
fields, this would require only two new entries in StandardizedVariants.txt and
be more flexible regarding alternate (Fairy Chess) game pieces – including
emojis.
Received on Sat Apr 01 2017 - 14:58:06 CDT