Improving categorical coloration
This MR changes the behavior of categorical coloration, improving it and adding some features.
- Annotation now always have a color, using a default and by looping when adding annotation after the size of the color map
- Automatic annotation generation can now be forced over its previous maximum (32)
- The Color Legend is now hidden automatically when the number of annotations if higher than the previous maximum (32)
- Opacity can now be set, globally, on selected category or on idividual category
- Tests have been added
Edited by Mathieu Westphal (Kitware)