Did you ever solve this problem?  Have you tried adjusting the camera?

FYI, Mark/Compute/Unmark, changes the positions.  Transform is only applied
at render time.


"Sharon Cady" <[EMAIL PROTECTED]>@opendx.watson.ibm.com on
02/13/2001 09:59:40 AM

Please respond to [email protected]

Sent by:  [EMAIL PROTECTED]


To:   [email protected]
cc:
Subject:  Re: [opendx-users] World Map coordinate system



I've already done the repairing of the line connection across the Int'l
Date
Line, so that is not a problem. I'm not sure that I see here a suggestion
about
what is my main problem - that of having a "view" of -180 - 180, even
though
the coordinates of the map points have been converted to 0-360 (i.e, half
of
the rectangular frame of the map is blank, since out of range map points
are
not plotted). Is Transform instead of Mark/Compute/Unmark the key, or do I
have
to modify the macro (or the WDBI data points) ? I've never used Transform -
what is the difference in its effect vs. Mark/Compute/Unmark of positions ?

On Feb 12, 10:48pm, Lloyd A Treinish wrote:
> Subject: Re: [opendx-users] World Map coordinate system
>
> The file, WDBI.dx, used by that macro has the coordinates as provided in
> the original World Data Bank I file.  The coordinates are raw lat-lon,
> cylindrical equidistant, with lon as degrees east (-180 to 180).  A
simple
> transformation such as Mark/Compute/Unmark or Transform will only
partially
> work.  The problem is lines that cross a nominal Int'l Date Line.  That
> transformation will force the "pen" to scrawl across the page.  You would
> have to check for these particular lines after the transformation and
> repair them.
>
> If you want to see ASCII, you can Import and then Export in an ASCII
flavor
> .dx file.
>
> The package of projections I put together some many years ago is geared
> around data in [lat degrees north, lon degrees east, +/- 180].  This was
> fine for my own needs at that time.  Since there was not much user
interest
> then, there wasn't much motivation to make them more general-purpose.
You
> would have to modify the map file or use a different one and/or modify
your
> data.  Some of the projections may have to be changed because of the
> different coordinates.  At least with everything as macros, you can see
how
> the projections work and modify them.
>
>
>
> "Sharon Cady" <[EMAIL PROTECTED]>@opendx.watson.ibm.com on
> 02/12/2001 02:58:07 PM
>
> Please respond to [email protected]
>
> Sent by:  [EMAIL PROTECTED]
>
>
> To:   [email protected]
> cc:
> Subject:  [opendx-users] World Map coordinate system
>
>
>
> I'm almost embarrassed to ask, since I'm obviously missing something
> (probably
> simple), but how do I shift the coordinate system of the cylindrical
> equidistant (rectangular) global map so that it goes not from -180 to
-180
> degrees longitude but instead ranges 0-360 ?
>
> There are inputs into WorldMapProjections which ask for centroid of the
> projections and also the range, but manipulation of these don't change
the
> positions of the points in the map, just the view of what is plotted (it
> seems). I've tried shifting the positions myself (mark/compute); however,
> with
> my new map ranging 0-360 longitude, I can only see the 0-180 part (the
> 180-360
> is ignored, apparently). Is there something somewhere which limits the
view
> of
> this plotted object ? I looked in the wdbi.dx file to see if I could find
> anything, but I didn't really see much in there, except binary data.
>
> I can get a map to plot which "looks" like how I want it, but of course
the
> positions are incorrect, since they are forced to range -180 - 180. My
data
> won't overplot on this, unless I juggle that all around too.
>
>
>
>-- End of excerpt from Lloyd A Treinish




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