Chess Diagram Methods

By George Jelliss

Chess Diagram

This diagram shows the latest version of my chess-piece designs for showing chess and variant chess diagrams on the internet, without making a separate image for each position.

Chess Piece Symbols
Opening Position

Each square of the board is a separate image. To be able to show all possible positions with orthodox pieces 26 images are needed: light cell, dark cell, white KQRBNP on light and dark, black KQRBNP on light and dark. The designs have been kept simple, for aesthetic as much as practical reasons. Each image was drawn in Lotus WordPro as 1.6 inches square, and the dark cells have 25% grey shading. The white pieces now have a black outline, though it has been necessary to make it heavier than I would prefer so that it shows up clearly in small diagrams. All the pieces are now available in four versions, upright, inverted and rotated to left or right to allow for representation of different fairy chess pieces (making 98 images in all).

Method of coding: The white and black cells are coded c00 and d00 (for clear and dark). To put chessmen on the cells the first 0 is replaced by k, q, r, b, n, or p to denote the type of piece. The second 0 is replaced by 1, or 2 to denote an upright white or black symbol, by 3 or 4 to rotate the symbol 90 degrees clockwise, by 5 or 6 to denote an upside-down symbol, and by 7 or 8 to rotate 90 degrees anticlockwise. To avoid confusion the images are kept in a subfile labelled 'x' so that they are retrieved by coding of the form 'x/cp1.gif' (for an upright white pawn on a clear cell).

Older Method of Showing Chess Diagrams

This older method uses less images and shows the cells as a table with alternating background colours in the cells. An attractive feature of this method is that the board colours can be varied. However in printing out webpages the background colours are omitted in the default setting, which some thought inconvenient. Also in the earliest versions the images for the white pieces had no black edges, so when printed without a coloured background they vanished. The images of the pieces are made with transparent background so that the colour shows through.

For diagrams with orthodox pieces only 13 images are needed, coded 0.gif (for a blank cell), 1b, 1k, 1n, 1p, 1q, 1r for the white pieces and 2b, 2k, 2n, 2p, 2q, 2r for the black pieces. To avoid confusion between this sets of symbols and those used for the diagrams above, I have put them in a file labelled 'y' so that the coding of say '2n.gif' becomes 'y/2n.gif'.

To show fairy pieces I made rotated versions of the images (as used on the BCVS website). Thus each of the 12 upright images was supplemented by inverted, right-rotated and left-rotated versions, making 49 images in all.