Re: [Gimp-developer] Some blend modes break in unbounded mode sRGB

[Michael Natterer <mitch gimp org>]

On Sun, 2014-04-13 at 12:00 -0700, Daniel Sabo wrote:
> This thread is huge and I’m not going to attempt to address
> everything, but in the context of:
>
> > 1. Multiplying and dividing by any color other than gray, black, or white.
> > 2. Any blend mode that involves multiplying or dividing, including burn, dodge, soft light, hard light.
> > 3. The lighten only, darken only, hue, saturation, color, and value blend modes.
>
> It is *completely trivial* to make the working space user selectable
> as long as it is some form of red-green-blue-alpha. The current gamma
> vs linear layer mode is an if statement in
> app/operations/gimpoperationpointlayermode.c :
> gimp_operation_point_layer_mode_prepare(); in paintcore it would
> involve changing the linear_mode boolean into a Babl format object.
>
> This does not apply to GEGL as a whole which is very fond of picking
> specific formats, but Gimp being able to switch between linear/gamma
> mode means most of the instrumentation for supporting custom working
> profiles is already there.

Sorry, not true :) It's rather pretty hard to do than "completely
trivial". Yes, all format magic is hidden behind well-defined
APIs and can be safely extended, but adding arbitrary formats
there is not so trivial.

Regards,
--mitch