clipka <ano### [at] anonymousorg> wrote:
> It might make /some/ sense to add a kind of "prgb" keyword; the rgb 
> keyword actually means "physical colors" /only/ if assumed_gamma is set 
> to 1.0. This interpretation of "rgb" is backward compatible with 3.6.

  I don't think "rgb" is generally considered to describe the amount of
radiant energy (measured in Joules) reflected by a surface (so that for
example "rgb 0.5" means that the surface reflects half of the incoming
radiant energy), but rather the *perceived* color of the surface (iow.
"rgb 0.5" means that the surface *looks* exactly half as bright as
"rgb 1").

  Measuring things in terms of perceived brightness is way more common than
in terms of absolute radiant energy. For instance, most SI units related to
light, such as the lux and the candela, measure perceived brightness.

-- 
                                                          - Warp

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