Index based color interpolation
This issue was created automatically from an original Mantis Issue. Further discussion may take place here.
When working with color tables, the interpolation of polygon elements is still in RGB and not based on the given color table. This should be corrected because it fakes the shown results. Like, I have a value in my color table which is by coincident the same color as the rgba interpolation between two edges of a polygon element, but has some complete different value...
For example, when you have a triangle, two edges red, one green and a palette/color table from red-black-green, the middle color should be black and not the interpolation between red and green, which is not present in the palette/color table.