KColor is coming this Monday...

Matthew Woehlke mw_triad at users.sourceforge.net
Sat May 26 01:05:11 BST 2007

Michael Pyne wrote:
> Zack's screenshot is pretty convincing [snip]

Well I would like to thank Zack for amply demonstrating the importance 
of API documentation. :-) And for making this demo so much easier to write.

Major problems with QColor::lighter/QColor::darker are...

WCT(Qt)S, it sure looks like darker() is lighter(100 - amt), or 
something along those lines. The main problem here is that I can't 
figure out how much a given color might need to be lightened by to get 
white; in KColor::lighten this is always 1.0. The Qt behavior 
(literally, multiplying luma/luminance by, erm, k, where k>1) is 
achievable with KColor::darken... using (drumroll please?) k>1. IOW 
KColor::darken(color, 1.5) == color.lighten(150).

Zack's screenshot looks "convincing" because he /asked/ KColor to tinker 
with the saturation as well as the luminance. Incidentally this is a 
KColor feature that QColor lacks. (Yes, I acknowledge that he probably 
did this because KColor isn't well documented yet.)

And for the grand finale, a demonstration of how QColor can't keep its 
hands off the saturation when you /don't/ want to play with it is 
attached. Note that the KColor bars do /not/ result in fully saturated 
colors when starting with a gray tone, whereas the QColor bars do. You 
can also note how the white point depends on the starting color with 
QColor, which is not true for KColor.

"Still the prettiest." -- Legolas
(as quoted in The Very Secret Diaries by Cassandra Claire)
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