LCH (shortest path) mode for blend-colors and Mix Colors

[GoogleCodeExporter]

The attached patch implements LCH (shortest h distance) interpolation mode for 
Blend Colors and Mix Colors. This looks similar in nature to 'HSV (shortest hue 
distance)' but is much better quality + more consistent. I currently use just 
the LCH mode (for getting painterly/vivid color transitions) and LAB mode (for 
all other transitions)

BTW, this is the same person as 00ai99@gmail.com, this is my new account.

I have not implemented a non-shortest-distance option, as I think this option 
is confusing and inconsistent (sometimes takes shortest path, sometimes takes 
longer.) IMO the better option is either to omit the non-shortest-path option 
(so, remove plain 'HSV' item from the options), or to make the 
non-shortest-path option always take the -longest- path (this is what GIMP 
does; so it has 'HSV shortest path' and 'HSV longest path').

I favor removing the non-shortest-path option personally (it doesn't seem to 
have a real use case), but am willing to implement either solution.
I opened this issue to get feedback on whether anyone uses the plain 'HSV' 
option or would use a 'longest path' option, and to give Albertas the 
opportunity to give his input or veto any removal.

Original issue reported on code.google.com by fintic...@gmail.com on 6 May 2013 at 2:17

Attachments:

• implement-lch-gradienting.diff

[GoogleCodeExporter]

In the absence of any feedback, I've committed this patch. Leaving this issue 
open because there is still the related issue of the inconsistency of the HSV 
blending modes ('HSV shortest hue distance' behaves consistently, but plain 
'HSV' sometimes takes the longest path and sometimes takes the shortest one, 
according to it's naive calculations.)

Original comment by fintic...@gmail.com on 22 May 2013 at 12:29

[GoogleCodeExporter]

I agree that the non "shortest hue distance" option can be removed as it is 
mostly useless.

Original comment by thezbyg on 11 Jun 2013 at 3:55

[GoogleCodeExporter]

This issue was closed by revision 885c6b48e38b.

Original comment by 00a...@gmail.com on 12 Jun 2013 at 2:30

• Changed state: Fixed

[GoogleCodeExporter]

I think that we can simplify HSV and LCH mode names. There is only one HSV, and 
one LCH mode now, and that makes long and descriptive names unnecessary, and a 
simple 'HSV' or 'LCH' should be ok.

Original comment by thezbyg on 14 Jun 2013 at 8:09

Attachments:

• hsv-mode-name.patch

[GoogleCodeExporter]

Good point, most people won't care about the difference between longest and 
shortest path anyway. Thanks, I've applied that and seem to have fixed my 
problem with the hg history branching and merging for no good reason, too.

Original comment by fintic...@gmail.com on 15 Jun 2013 at 1:27