----- Mail original ----- > On 04/21/2014 04:47 AM, Teo Mazars wrote: > > > > > > ----- Mail original ----- > > >> Similar issues are easy to demonstrate with Levels upper and lower > >> sliders, Gradients, Invert. These really need to be linear light > >> operations. > >> > >> Is there a list of the operations that don't currently use linear > >> light? > > > > Yes, grep for "R'" or "Y'" in the operation directory. > > Thanks! > > > But... are you really saying that Gradient should be implemented > > using a non-perceptual color space? > > Yes, to be technically correct. > > See > http://ninedegreesbelow.com/gimpgit/gimp-srgb/gradients/gradients.png > > > > I think gradient is a good simple example. How this operation > > should be implemented exactly? > > We want people to be able to draw perceptually linear gradient right? > > I completely agree with you that people should be able to draw a > gradient in a perceptually uniform color space if they want to. > > But any such gradient is not technically correct. Colors don't mix > properly in the almost perceptually uniform regular sRGB color space. > > So any color mixing in the regular sRGB color space is technically > incorrect. For example, you get dark lines at the edges of soft brush > strokes. The same thing happens with gradients, except the darkening > artifact is spread out across the gradient and so doesn't look as > obviously technically incorrect. Hmm, I understand, then the default black-to-white gradient would be non perceptually linear, which is more surprising than the color-to-color gradient. I think I am now convinced this is correct, but it will probably be puzzling to use. BTW, "gradient" is not such a good example because it's not related to chromaticities, "Invert" would be a better one. _______________________________________________ gimp-developer-list mailing list List address: gimp-developer-list@xxxxxxxxx List membership: https://mail.gnome.org/mailman/listinfo/gimp-developer-list List archives: https://mail.gnome.org/archives/gimp-developer-list
