Robert McGregor schrieb:

> Now my only real issue is with gamma pre-correction on my image map files (so
> v3.7's linear 1.0 rendering and post file_gamma correction don't wash out my
> image maps). I'd like to be able to simply tell POV-Ray to gamma pre-correct my
> input images as needed by using some simple math, say 1.0 divided by display
> gamma, something like:
> 
> image_map { jpeg "myfile" pre_gamma 1/2.2 }
> 
> Then when using any PNGs with embedded gamma I could skip that (or just use
> pre_gamma 1)
> 
> Is that anything like what's planned/coming in the future?

Yes, definitely. As a matter of fact, a corresponding patch has been 
implemented already, and I expect it to feature in the next beta.

The syntax will differ in some details of course; for instance, the 
keyword is likely to be "file_gamma" and the parameter value will 
actually be the inverse of your proposal; it will also be conceptually 
an override, not an additional adjustment, which will make a difference 
for PNG files; e.g. if a PNG file is encoded pre-corrected for a display 
gamma of 2.2, and "file_gamma 2.2" is specified, POV-Ray will still 
apply a total gamma adjustment of x^2.2, not x^(2.2*2.2).


> (And thanks for bearing with me on this gamma issue everyone - I needed to
> educate myself a bit on this topic - never really considered it much until very
> recently)

I guess you're not the only one. I didn't wrap my head around it in a 
single day either.

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