From: Viktor Szakáts <harbour...@syenar.hu> Sent: Saturday, February 20, 2010 3:22 AM Subject: Re: [Harbour] SF.net SVN: harbour-project:[13878] trunk/harbour
> Hi Andrzej, > >> From: <vszak...@users.sourceforge.net> >> >>> Revision: 13878 >> [...] >>> * contrib/hbwin/hbwin.ch >>> * Changed to use full (0xFF) color components for RGB presets. >> >> Viktor, this change is incompatible with Clipper. Previous colours >> were too dark, but 0xFF should stand for BRIGHT colours. Clipper uses >> RGBI palette, see here: >> * 4-bit RGBI palettes for explanation: >> http://en.wikipedia.org/wiki/List_of_monochrome_and_RGB_palettes#4-bit_RGBI >> * EGA colour palette for hex values in implementation: >> http://en.wikipedia.org/wiki/Enhanced_Graphics_Adapter#The_EGA_color_palette > Clipper had no graphical printing, nor any special color > printing support for that matter, RGBI palette is NOT for printing. I did NOT mention about printing at all. > nor did it determine the > actual colors that appeared on screen, so it's by no means > a Clipper compatibility issue. Clipper did NOT define any *own* palette, it just used CGA palette available in DOS. The palette is used as CGA compatibility palette in EGA/VGA/Windows till now. > If you mean to mimic MS-DOS (or rather VGA/EGA) screen colors > in Windows printing, I can't see strong reason why this would > be desired. I am not DTP professional, but I know at least two facts: * You cannot mix RGB and CMYK colour models. RGB is for screen, CMYK is for printing. All RGB_* #defines are in RGB colour model, so they are not to be used for printing. See: http://en.wikipedia.org/wiki/RGB_color_model * There is no simple colour conversion from RGB to CMYK. See: http://en.wikipedia.org/wiki/CMYK_color_model#Conversion As you already know, Clipper did NOT define any print colours and did NOT use any known printing colour palette. We can use system colour management (see <http://en.wikipedia.org/wiki/Color_management>) or define our own colour conversion scheme, but the palette should contain all 16 colours, normal and BRIGHT. > --- (from old hbwin.ch) > #define RGB_BLACK RGB( 0x00, 0x00, 0x00 ) > #define RGB_BLUE RGB( 0x00, 0x00, 0x85 ) > #define RGB_GREEN RGB( 0x00, 0x85, 0x00 ) > #define RGB_CYAN RGB( 0x00, 0x85, 0x85 ) > #define RGB_RED RGB( 0x85, 0x00, 0x00 ) > #define RGB_MAGENTA RGB( 0x85, 0x00, 0x85 ) > #define RGB_BROWN RGB( 0x85, 0x85, 0x00 ) > #define RGB_WHITE RGB( 0xC6, 0xC6, 0xC6 ) > --- Once again, the above colours are in RGB colour model. They are defined for display, not for printing. That is not full Clipper colour palette, only non-BRIGHT part, and brown defined here is not brown on screen. > F.e. why isn't "white" 0x85/0x85/0x85 to be consistent > with other colors, or even more, why isn't it pure white: > 0xFF/0xFF/0xFF, instead of being grey? :) I DID write and you DID quote: "Previous colours were too dark", that's why they are inconsistent. I DID also write "0xFF should stand for BRIGHT colours", that's why white is really light grey. And I know that real white may be darker then the displayed one[1]. I linked also the explanation, why brown setting should be inconsistent, did you read it? I don't know why someone used such RGB values for the old colours – maybe he/she picked them from his/her own display or corrected them as CGA colours were too bright in his/her opinion. Still they are colours defined in RGB colour model, that is – for display, not for printing. [1] A good example for troubles with colour conversion for "red" and "white" you can see here: http://en.wikipedia.org/wiki/Flag_of_Poland#Design http://en.wikipedia.org/wiki/File:Flag_of_Poland.svg http://commons.wikimedia.org/wiki/File:Flag_of_Poland_(normative).svg Maybe on your screen you cannot see differences between the flag and the background colour in any places, but they are. Use some colour picker to check RGB codes or use some good old CRT monitor. -- Regards from The Harbour Project mirror in Poland Andrzej P. Woźniak ------ Hosting 2GB za 40 zl brutto http://www.klatka.pl _______________________________________________ Harbour mailing list (attachment size limit: 40KB) Harbour@harbour-project.org http://lists.harbour-project.org/mailman/listinfo/harbour
