Hi Jianting,
> I need to draw a rectangle (using DirectManipulationRendererJ2D)
> interactively on top of a big regular scalar map. It seems that all the
> maps will be redrawn for a single user click which is very time
> consuming. Is there any way to not draw the big scalar maps (while still
> keep them as background) to make the drawing faster?
First, the map won't be re-transformed but only re-rendered.
The transform is the slow part. But if the render time is a
problem, please consider using Java3D instead of Java2D.
Java3D is much faster.
Good luck,
Bill