Hi. I try to adjust the Scalar mapping for the RGB or IsoContour and having some problem in that. As far as I know, the VisAD is using the linear scaling method to map the colour for the values. My requirement is for a range of figures with negative and positive values, I want to specify a certain colour for -ve values, another colour for zero, and different colour again for +ve values. On top of that, the linear scaling can be applied for individual regions to project a better view. May I know how should I do that? Thank you for all who read my emails and response to my mail. Have a nice day.