On 2016-04-09 09:02, Curtis Mitch wrote: > Is there any technical reason (besides compatibility) why QColor::hslHueF() > can't return a value between 0 and 1? > > If the colour being represented by QColour is black, QColor::hslHueF() will > return -1:
I think there is a misunderstanding here... a negative value is an "error". Specifically, you get a negative value for hue when the value cannot be meaningful, because the color is fully desaturated (i.e. a "perfect" shade of gray). Any value for hue for such colors is necessarily going to be arbitrary. Qt happens to have made the choice (which I think is a good one) to return a value that indicates this clearly, rather than returning an arbitrary value from the normal range, which might incorrectly imply that the value is meaningful. > how would I work around the case of a negative hue? Ideally, you should teach your application how to understand when the hue is not meaningful and to behave in such cases in a reasonable manner. Failing that, you could just map a negative value to an arbitrary value in the normal range. (For example, you could always map hue like `qMax(0, h)`.) -- Matthew _______________________________________________ Development mailing list [email protected] http://lists.qt-project.org/mailman/listinfo/development
