Re: how to fill in pixels

> I assume that your (radial, gate) are polar coordinates.
> Rather than ScalarMaps x -> XAxis and y -> YAxis, try
> ScalarMaps of radial and gate to Radius and Longitude,
> which are VisAD display polar coordinates (which along
> with Latitude form display spherical coordinates for
> 3-D displays).

This does not quite work, because there is no way to get the 
elevation of the conical surface in ... (I get a projection on
what I assume is the earth's surface). But your comment (below)
gave me the right solution.

> Filled displays require a topology for interpolating
> between points, and that topology needs to come from
> the domain Set of a Field. Hence filled displays need
> ScalarMaps from domain RealTypes of a Field.

I changed the MathType from
  (radial,gate)->(x,y,z,gatevalue)
to:
  (radial,gate) -> (x,y,z) -> (gatevalue)
and attached the x,y,z axes to the Display axes
and I do get filled pixels. 

I then used a gridded 3D set
with manifold dimension of 1 for the second MathType,
so that the x,y and z were domain RealTypes ...
Is this very inefficient?  What exactly is that irregular
set doing? Is it interpolating or doing a nearest neighbor?
How can I control this?



> I recommend using setTable() rather than setFunction(),
> which is rarely used and possibly buggy. You can define

setTable() works, thanks!

Lak