Am 05.03.2012 23:43, schrieb Christian Froeschlin:
> clipka wrote:
>
>> That's only true if you define colors the old way, using "rgb" rather
>> than the new "srgb". With POV-Ray 3.7, it's not a matter of which
>> assumed_gamma setting gives you a more intuitive way to specify
>> colors, but a matter of choosing between intuitive ("srgb") and
>> physical ("rgb") colors.
>
> Actually this now made me wonder if 3.7 should redefine the rgb
> keyword to mean "intuitive colors" (srgb) and introduce a new keyword
> for "physical colors" (prgb).

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.

> The change in gamma handling would then come simultaneously with
> a change in rgb interpretation that mostly cancels out for existing
> scenes that already used assumed_gamma 1.0, reducing all the whining
> about "my image is too washed out", and the new gamma handling could
> be used without having to adapt all existing textures at once.

Strictly speaking, POV-Ray 3.7 doesn't introduce a fully new gamma 
handling concept at all; it just (1) obsoletes the 3.6 default of not 
performing any gamma handling at all (in favor of "assumed_gamma 1.0" 
mode; you can still get the 3.5 handling by specifying "assumed_gamma 
srgb"), and (2) complements the 3.6 assumed_gamma-based handling with 
some tools that were lacking in 3.6, especially to work with colors from 
external sources - whether they are images (except for PNG, 3.6 provided 
no way of gamma-adjusting input images that didn't happen to match the 
assumed_gamma) or explicit color values.

Also note that if you don't explicitly specify a "#version" statement, 
POV-Ray 3.7 /does/ warn you, so it's not like POV-Ray isn't giving 
people any hints at all. (And with "#version 3.6" you do get the old 
behaviour.)

Post a reply to this message