Color perception is unfortunately not simple. The spectral distribution of the light illuminating a scene is highly variable in nature and is a strong contributor to what colors we see and how bright different wavelengths appear. There are also variations in the distribution of the cones in our eyes that see different portions of the visible spectrum. Color spaces used in computer graphics are often nonlinear. Any color manipulation in computer graphics is only a approximation, and these approximations can be improved with more sophisticated color management schemes which often use large 3-dimensional lookup tables and interpolation techniques. Unfortunately a simple 3 term linear conversion such as the existing functions in blender are wrong, and changing a few values here and there will not make them any more correct, because as soon as the illumination or the surrounding scenery changes, perception changes. A 3-slider interface that allows user tweaking of these values may be seen as an improvement but is unfortunately dependent on the perception of the user who is manipulating them. This allows more flexibility but is not correct as there are still non-linearities in color spaces.
A more "correct" wan may be to have a user manipulated 3-term spine graph, similar to the Image->Adjustments->Curves... dialog in Photoshop, with appropriate defaults this may at least allow for correction of gross errors or non-linearities. Then again, probably few of us would notice the subtle improvements such flexibility would allow, and if one really wanted a high quality conversion it could be done in an application specifically designed for such a task prior to adding it to a Blender scene. I would tend to agree with Campbell about not changing any conversions which may drive effects such as displacement maps. Perhaps the functions in question could be renamed to better describe how they are used in other parts of blender, and documented as Campbell suggested. I don't think there's goring to be a "correct" solution that uses 3 linear terms and a "proper" solution will likely require significant of expertise and effort. On Mon, Jun 25, 2012 at 2:50 PM, Knapp <[email protected]> wrote: > I really like the idea of having a node that lets you adjust the rgb > scalars. Perhaps it would have presets for newbies based on the > standards. > > > > -- > Douglas E Knapp > > Creative Commons Film Group, Helping people make open source movies > with open source software! > http://douglas.bespin.org/CommonsFilmGroup/phpBB3/index.php > > Massage in Gelsenkirchen-Buer: > http://douglas.bespin.org/tcm/ztab1.htm > Please link to me and trade links with me! > > Open Source Sci-Fi mmoRPG Game project. > http://sf-journey-creations.wikispot.org/Front_Page > http://code.google.com/p/perspectiveproject/ > _______________________________________________ > Bf-committers mailing list > [email protected] > http://lists.blender.org/mailman/listinfo/bf-committers > _______________________________________________ Bf-committers mailing list [email protected] http://lists.blender.org/mailman/listinfo/bf-committers
