💡📝H. G. Muller wrote on Tue, Oct 10, 2017 08:40 AM UTC:
Indeed, this is no good. Part of this is Nicolino's fault, by using too dark shades for the normal board checkering; it seems his light shade is already as dark as what I use (and is default) for dark squares. But especially yellow, used to highlight non-captures, is too bright to show up well in grey scales. I guess color coding is not an ideal method on grey-scale devices, unless you are very careful in selecting the colors.
It seems to be difficult to detect if you are running on a grey-scale device from JavaScript. My e-reader still reports screen.colorDepth 16, as opposed to my laptop, which reports 24. Perhaps I should have the diagram use a darker shade of yellow (or perhaps of every color) when running with colorDepth <= 16, assuming most color displays nowadays have at least 24-bit 'true colors'.
[Edit] I have now modified the script to detect colorDepth (after the initial rendering), and adjust the square shades to pure white and very light grey if this is <= 16, irrespective of what the user defined. A darker shade of yellow is then used for 'move or capture' highlights. Ufortuately I don't know how to test if this is satisfactory; I have an old and cheap model Kobo e-reader, it has a browser, but I do not know how to flush its cache. So it keeps using on the old, cached script...
#FFFFFF: Light squares
#E8E8E8: Dark squares (grey scale)
#E0E0E0: Dark squares (default)
#FFFF00: Move or capture (color)
#F0F000: Move or capture (grey scale)
#FFE000: Jump move or capture
#D0D000: Initial move or capture
#00F000: Move only
#00B000: Initial move only
#00FFFF: Locust capture (destination click to follow)
#FF0000: Capture (only)
#0000FF: Capture own piece
#505050: Forbidden King move
It does help a bit that some colors will only be used on empty squares, others only on occupied square.
The move-only and move-or-capture colors will only be used on empty squares.
While playing on the diagram (locust) capture will only occur on occupied squares.
Unfortunately in the move diagrams capture is also indicated on empty squares;
perhaps I should switch to displaying a dummy black piece on the target squares in that case.
[Edit] What also helps is to not use checkering of the board at all when displaying a move diagram. I guess there is no need at all for checkering in that case; the checkering is only useful when you are playing, and want to know if a distant diagonal mover now hits one of your pieces. In a move diagram diagonal moves are highlighted themselves.
Another trick I learned: I can safely use floating style for a diagram in a comment, when I put the whole comment inside a 1x1 table. Then it will ever stick out into the comment below it, not even if you open the legend below the diagram. I tried this in the Wildebeest diagram; I needed the floating style to be able to get the pieceList and board in the same view, so that I could touch the pieces in the list and see their diagram appear, as my e-reader as a portrait-shaped screen, and the diagram and list would not fit side by side.
Indeed, this is no good. Part of this is Nicolino's fault, by using too dark shades for the normal board checkering; it seems his light shade is already as dark as what I use (and is default) for dark squares. But especially yellow, used to highlight non-captures, is too bright to show up well in grey scales. I guess color coding is not an ideal method on grey-scale devices, unless you are very careful in selecting the colors.
It seems to be difficult to detect if you are running on a grey-scale device from JavaScript. My e-reader still reports screen.colorDepth 16, as opposed to my laptop, which reports 24. Perhaps I should have the diagram use a darker shade of yellow (or perhaps of every color) when running with colorDepth <= 16, assuming most color displays nowadays have at least 24-bit 'true colors'.
[Edit] I have now modified the script to detect colorDepth (after the initial rendering), and adjust the square shades to pure white and very light grey if this is <= 16, irrespective of what the user defined. A darker shade of yellow is then used for 'move or capture' highlights. Ufortuately I don't know how to test if this is satisfactory; I have an old and cheap model Kobo e-reader, it has a browser, but I do not know how to flush its cache. So it keeps using on the old, cached script...
It does help a bit that some colors will only be used on empty squares, others only on occupied square. The move-only and move-or-capture colors will only be used on empty squares. While playing on the diagram (locust) capture will only occur on occupied squares. Unfortunately in the move diagrams capture is also indicated on empty squares; perhaps I should switch to displaying a dummy black piece on the target squares in that case.
[Edit] What also helps is to not use checkering of the board at all when displaying a move diagram. I guess there is no need at all for checkering in that case; the checkering is only useful when you are playing, and want to know if a distant diagonal mover now hits one of your pieces. In a move diagram diagonal moves are highlighted themselves.
Another trick I learned: I can safely use floating style for a diagram in a comment, when I put the whole comment inside a 1x1 table. Then it will ever stick out into the comment below it, not even if you open the legend below the diagram. I tried this in the Wildebeest diagram; I needed the floating style to be able to get the pieceList and board in the same view, so that I could touch the pieces in the list and see their diagram appear, as my e-reader as a portrait-shaped screen, and the diagram and list would not fit side by side.