Re: drawing arrows

Hi Donna,

With your ScalarMaps of u to Flow1X and v to Flow1Y, try
experimenting with calls to the setScale() method of the
FlowControl. See visad/examples/ for an example.

You can also draw a bunch of lines between points as a
UnionSet of Gridded2DSets with manifold dimension = 1.
See visad/examples/ for an example.

Good luck,

On Thu, 7 Aug 2003, Donna L Gresh wrote:

> Is there a simple way to simply draw a set of arrows from one set of
> points to another? (my desire is to show the displacement of a set of
> points)
> I have set up a FlatField mapping (x,y) ->(u,v), where the (u,v)'s I've
> computed as the difference between x1,y1 and x2,y2. Thus I'd like to draw
> lines starting at points x,y with length u,v.
> I've tried constructing a scalarmap of u to Flow1X and v to Flow1Y, but
> nothing seems to appear in the display. It may well be that I'm still not
> doing things exactly as they should be, but is this the right approach?
> Donna L. Gresh, Ph.D.
> Optimization and Mathematical Software Group
> IBM T.J. Watson Research Center
> (914) 945-2472
> gresh@xxxxxxxxxx