The "Color" layer mode has since long produced bad results, see bug
325564  for a way to see this. The cause is a combination of rounding
errors due to 8bit processing and poor properties/usage of the
underlying color model HSL.
I have just implemented Color based on the CIE LCH color model when GEGL
is used for the projection. This gives much better results, see the bug
report for samples.
Now, I would also like to port Hue, Saturation and Value to CIE LCH.
They are currently using the HSV color model with the same problems as
HSL. If we switch to CIE LCH we would also change name of "Value" to
Does anyone see any problems with using CIE LCH instead of HSV for these
layer modes? We can ignore backwards compatibility issues for now.
Thanks in advance for any input
Bug 325564 – Use CIE LCH instead of HSL for layer mode "Color"
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