Color ramp HSV, Far-mode have wrong behavior #49979

New Issue

Vyacheslav Kobozev · 2016-11-10T00:21:19+01:00

2016-11-10 00:21:19 +01:00

Cycles, material node editor, RGB-
Blender Version
Broken: 2.78

As you can see.
The first: when I move H to 1, it become`s zero. Ok, I know HSV is circle and it is the same. But still not useful.
But it would be nice if the last H will be not 0=1, but 0.999

CW or CCW modes have correct behavior, because it is impossible to say where 1 from 1, left or right.
Far mode should go the longest way: all around the HSV-circle. And it should looks like this:

For now the solution is set 0.999 on the left color node manually.
idk, may be it is not a bug of Blender, but misunderstanding of Far-mode.

Cycles, material node editor, RGB- **Blender Version** Broken: 2.78 ![2016-11-10_012627.png](https://archive.blender.org/developer/F396056/2016-11-10_012627.png) As you can see. The first: when I move H to 1, it become`s zero. Ok, I know HSV is circle and it is the same. But still not useful. But it would be nice if the last H will be not 0=1, but 0.999 CW or CCW modes have correct behavior, because it is impossible to say where 1 from 1, left or right. Far mode should go the longest way: all around the HSV-circle. And it should looks like this: ![2016-11-10_021801.png](https://archive.blender.org/developer/F396063/2016-11-10_021801.png) For now the solution is set 0.999 on the left color node manually. idk, may be it is not a bug of Blender, but misunderstanding of Far-mode.

Vyacheslav Kobozev commented

2016-11-10 00:21:19 +01:00

Changed status to: 'Open'

Vyacheslav Kobozev commented

2016-11-10 00:21:19 +01:00

Added subscriber: @Vyach

Charlie Jolly commented

2017-08-21 15:48:31 +02:00

Added subscriber: @CharlieJolly

Charlie Jolly commented

2017-08-21 15:48:31 +02:00

This is partly a limitation of how colours are picked and stored in Blender as RGB values. This means that when selecting a red with a Hue of 0 or 1 it is converted to the same RGB value which is what is stored, The hue value used in the ramp is determined from an RGB to HSL/V conversion. A potential fix for this would mean adding the ability to store Hue values when selecting colours which would result in the correct interpolation.

Charlie Jolly commented

2018-11-01 16:04:14 +01:00

The following patch changes the behaviour of the FAR mode to force interpolation if the hues are the same. The direction is set to CW in this case. This also means that you wouldn't be able to set an area of the same colour.

T49979_fix.diff

The following patch changes the behaviour of the FAR mode to force interpolation if the hues are the same. The direction is set to CW in this case. This also means that you wouldn't be able to set an area of the same colour. [T49979_fix.diff](https://archive.blender.org/developer/F5325495/T49979_fix.diff) ![image.png](https://archive.blender.org/developer/F5325498/image.png)

Vyacheslav Kobozev commented

2019-02-14 05:45:45 +01:00

Still the same problem. Far is not far-around.

Still the same problem. Far is not far-around. ![070214.jpg](https://archive.blender.org/developer/F6605717/070214.jpg)

Charlie Jolly commented

2019-02-14 12:22:43 +01:00

Did you apply the patch? This is just a suggested fix and this bug probably needs reviewing by the UI team.

Vyacheslav Kobozev commented

2019-02-14 16:46:42 +01:00

Okay, I see. Thanks.

blender-admin commented

2019-03-19 19:50:30 +01:00

This issue was referenced by 2691dd28e7

This issue was referenced by 2691dd28e7dc085d0ae0aef219c433d4521fc326

Bastien Montagne commented

2019-03-19 20:51:11 +01:00

Added subscriber: @mont29

Bastien Montagne commented

2019-03-19 20:51:11 +01:00

Thanks for the patch, added a review about that change (and fixed original patch that had some issues in some cases, e.g. with two stops on red and blue, would generate 1.6666 turn into the hue space ;) ).

Bastien Montagne commented

2019-03-24 18:33:57 +01:00

Changed status from 'Open' to: 'Resolved'

Bastien Montagne closed this issue

2019-03-24 18:33:57 +01:00

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Color ramp HSV, Far-mode have wrong behavior #49979