> I have a display and for each position I want to display 4 vectors: one
> to the North, South, West and East. Now I think this is easiest when I
> use the FlowControl facility. But I don't get the vector to the South or
> West when I use Display.Flow1X and Flow1Y. If I use a negative number my
> arrow is gone.
> When I use Display.Flow1Azimuth and Display.Flow1Radial, the vectors has
> a wrong angle with my display.
I just ran a couple tests, using the SpreadSheet to display
GIF r, g, b values as Flow1X, Y & Z (offset by a negative
number to give both signs), and using BarbRendererJ3D in
visad.bom, for Cartesian and polar winds, and all worked
correctly. So I don't know what your problem is.