I'm working with a transformed map object (NPoleOrtho), so the coordinates
aren't in degrees. I am able to feed to Camera the range of these coordinates
whatever they are (I didn't really realize this when I posted this question),
and get a fairly reasonable view.

The real problem I'm having in sizing the window now is the polar-projected
map. This is not really a Camera question any more, I don't think, it is a
projection question.

When I subset a cartesian map by lon/lat to get the region of interest, make a
polar projection of the result, and then overlay this with the polar-projected
data, there is too much map extending south in relation to the data. This extra
map area takes needed window real estate. It seems that for a regional polar
map created this way, the min latitude (which determines the southern boundary)
that I input to WorldMap-projections needs to be greater than it would be for a
rectangular map, in order to avoid unnecessary map. I am guessing at some value
(10% of the range, or something like that), but it would be nice if I had some
kind of formula to get it just right.

Does this sound like the result that you would expect to see if subsetting a
rectangular map, then polar-projecting it ?

On Mar 27,  8:21pm, Lloyd A Treinish wrote:
> Subject: Re: [opendx-users] Camera view for polar projection
>
> Given DX's cartesian camera, a full hemisphere view will have a width of
> 180 for that projection.  If the aspect < 1, it will cut off the top and
> bottom.  So, you should adjust for aspect or having the window bigger to
> accommodate legends, etc.
>
>
> "Sharon Cady" <[EMAIL PROTECTED]>@opendx.watson.ibm.com on
> 02/15/2001 12:22:05 PM
>
> Please respond to [email protected]
>
> Sent by:  [EMAIL PROTECTED]
>
>
> To:   [email protected]
> cc:
> Subject:  [opendx-users] Camera view for polar projection
>
>
>
> Lloyd or others,
>
> I'd like to define a camera which will automatically set the appropriate
> view
> to zoom in on a specified chunk of data which has been polar projected
> (N-Pole-Ortho). With a rectangular projection, I can just set the camera
> view
> to be some % > the longitude range. But this does not work to size the
> polar
> projected data.
>
> Thanks,
>
> Sharon
>
>
>-- End of excerpt from Lloyd A Treinish

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