Hi Rakesh,
> I have got a display with a 3D surface.In the same display i
> want to have a line which grows gradually(animatio)..like (x1,y1,z1)-->(x2,
> y2, z2)-->(x3, y3,z3).
> can anyone give me a clue?
As Ugo explained, you can draw your line with a Gridded2DSet
with manifold dimension = 1. You can animate by making a loop
inside which you repeatedly construct a new Gridded2DSet with
differen values and pass it to DataReference.setData(). You'll
find an example of this in the while loop in visad/python/stroud.py.
The makeBody() function constructs a UnionSet of Gridded3DSets
with manifold dimension = 1, and is called repeatedly inside the
while loop, along with setData() and Delay(50).
Good luck,
Bill