Hi Bill, thanks for the reply.
I like your suggestion of using the examples/Rivers.java approach.
However, a comment you made confuses me (see below) You mentioned how to
give the 'arrow' a visual direction by placing a square at the RP end, and
that would use a SECOND flatfield. If this is the case, what is the first
flatfield? In Rivers.java it appears to me that there is no flatfields at
all, and no function types.
This also leads me to think, without a function type and flatfield for the
'arrows', any new arrow set on a display will require a
removeReference/addReference pair?? Even though the FP points will be the
same but the RP points will change, I will have to replace one Data with
another??
Any help gratefully appreciated.
Stuart
> > gridded2Dsets where in each set I have two points FP and RP, and union
> > this over all points in the set of displacements. The problem here is
> > that I wouldn't see any 'flow' of the displacement, since the rivers have
> > no 'direction'.
>
> The good thing about this approach is that you are "drawing"
> in data space, so any CoordinateSystems, Units and ScalarMaps
> are automatially taken into account. You could always "draw"
> the arrow heads too, with each Gridded2DSet in your UnionSet
> having 5 points instead of two. Or, instead of a normal arrow
> head, you could just create a large square at one end of each
> arrow by displaying a second FlatField of just the RPs, with
> a ConstantMap of (say) 3 to PointSize passed with the
> addReference() call.
>
