Le 28.11.2007 15:19, Warp nous fit lire :
> Le Forgeron wrote:
>> I'm wondering why, short of historical reason, does the
>> interpolation of weighted textures(pigment) is performed in the rgb
>> space.
>>
>> Wouldn't it be possible to perform it in HSV or HSL space
>   While this could work, I'm not exactly sure how it's different from a
> direct RGB interpolation. I haven't tested it.

I had a try with RGB (the pov current way), HSL & HSV. (see attached
picture)

First row is RGB interpolation
Second HSL
Third HSV.

There is no point in trying YUV/YIQ/Secam/Pal/NTSC... colorspace as
they are matrix transformation of RGB, and as such keep the same result.

First column is Pure colours (<1,0,0>),
Second column is Light colours (<1,0.5,0.5>)
Third column is dark colours (0.5,0,0),
Fourth column is Green & Cyan, with dark & light.

The original colours are in full-disc.
The interpolated colours are in opened-disc, at mid-way between the
used colours. The center open-disc is the interpolation of the three
original colours. The opened-disc on the side is the interpolation
of the three first-level interpolation.

There is differences!
For the management of Shades, I prefer HSL: mixing dark & light
gives normal, which does not happen for HSV nor RGB!

-- 
The superior man understands what is right;
the inferior man understands what will sell.
-- Confucius

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