On Wed, 2004-11-24 at 15:26, Karl Ove Hufthammer wrote: > Yes, I know. But that doesn't mean that a greyish blue is a > *good* colour to use for drawing cartoon-like sky in a childrens' > program. We don't need photo-realistic colours; we need useful, > good-looking colours. > > >> I'm really tired of apps using only fully-saturated colours.
Conflict? :-) > > In the sRGB color space, blue is dark and saturated. > > Yellow and cyan are not saturated. > > I did not know that sRGB defines a formula for saturation. But at > least in my image processing progams, both bright yellow and > bright cyan have full (100%) saturation (the HSL colour model). > This is also in line with how the word 'saturation' is used in > everyday language. The sRGB space maps to the CIE XYZ space, which is based on careful measurement of human subjects comparing colors. There is a perceptually uniform mapping of CIE XYZ, called the L,a*,b* color space, that is very human-friendly if you put the "a" and "b" part into polar coordinates. The radius is saturation, and the angle is hue. The HSL color model, to put it bluntly, is a disaster. Surely you don't believe that yellow and cyan have the same saturation and brightness, yet HSL would have this be so. > > If we had more slots (could be an option -- they get smaller) > > We actually had fewer in earlier versions. But I really don't want > to increase the number. A better solution would be a palette tool. > See bug #1070398: > http://sourceforge.net/tracker/index.php?func=detail&aid=1070398&group_id=66938&atid=516298 That's not an easy user interface, unless the palette simply sits where to color picker does today. I guess that means multiple rows. Three rows in a honeycomb layout would be OK. > Yes, I know. That's why I don't like to use 'silver' as a colour. > What I didn't understand was why you thought 'light grey' might be > difficult to read. lig-hit grey > >> But anyway, the buttons for all the greyscale colours look > >> almost the same, so we should think about removing some of > >> them. I'll try to come up with a proposal for a new colour > >> palette. > > > > No, we should think about changing the way the buttons look. > > Either that, or live with it. The current buttons are pretty, > > but they don't handle all of the colors well. We need all 4 > > shades of grey -- I didn't change them, BTW. > > Why? Do kids use all shades of greys in their images? (Ordinary > crayons often doesn't even contain *one* shade of grey.) I would > rather believe that 'colourful' colours would be useful. And > there's always the darken/lighten tool if you really need more > greyness. Crayons are easier to control for light/dark. The fade tool is nowhere near as easy and accurate. > I think black, white and grey (around 50 % black) should suffice. I was thinking that a 3rd grey would be nice. > >> (This is easier said than done. One important thing to be > >> aware of, is that all colours must give different tints when > >> tinting stamps. We had a problem with magenta and purple > >> before. The two colours looked completely different, but gave > >> the same colour when tinting stamps. Some very minor > >> modifications to the colour values fixed this.) > > > > I don't think that's a big problem. I'd rather have the > > original magenta and purple. (didn't change it back though) > > If the tinting code doesn't handle brightness, then that's > > the problem that needs fixing. Choosing less-desired colors > > to work around this problem hurts much more than the minor > > limit on the few rare tintable stamps. > > The stamp tinting code tints stamps to the tint of the colours, > and AFAICS works correctly. The colours were the problems, and > were easy to fix. The new colours weren't less-desired, The tinting code does not work correctly, because it ignores the brightness. Purple is dark magenta. I'm not sure what to call that color there now, but it isn't purple. Purple-blue? The original was much nicer. For good tinting, you really need a second grey+alpha image. For a reasonable job using the current image files, this might work: 1. convert stamp to L,a*,b* 2. find the average color 3. find the most saturated color with a hue within a few degrees of the average color (this will be considered the old color and hue) 4. without modification, copy over all pixels with a hue that is more than a few degrees from the old hue 5. change hue of remaining pixels 6. scale the saturation to match the new saturation 7. adjust brightness along a linear slope that is along the hue axis, such that the old color becomes the new color and a half-saturated color with the old hue will have a brightness change that is half that of a full-saturation color (as the saturation approaches zero, so does the brightness change) _______________________________________________ Tuxpaint-dev mailing list [EMAIL PROTECTED] http://tux4kids.net/mailman/listinfo/tuxpaint-dev
