Hello All,
I wanted to confirm my understanding of how IDV 1.2b1 handles map
projections and ask a couple of related questions.
1) an IDV "projection" combines the map projection with maximum spatial
extent ("Default Zoom"). This is a spatial clip of the data and not
actually a limit on the minimum scale.
2) the Default Zoom cannot be edited via the Projection Manager and can
only be edited manually in the
$HOME/.metapps/DefaultIdv/projections.xml. There is no import facility
to bring in an externally-created projection definition.
3) only 4 map projections: Geographic (unprojected), Lambert Conformal
Conic, Transverse Mercator, and Stereographic are supported.
4) When the "Reset Projection With New Data" option is selected, the
display is set to the geographic extent of the last dataset added and
all previously added datasets are not only clipped/zoomed in, but
reprojected to the current map projection. If this option is not
selected, datasets using different projections are overlaid without
re-projecting the data.
Can someone please correct or confirm these assumptions?
Also, can someone point me to the facility for programatically
adding/editing Saved Projections as an alternative to using the GUI
Projection Manager?
Is there a way to get information about the current projection? For
example "Reset projection with new data" is true, one adds a new
datasource/display, and the projection is changed. How can I find the
parameters of this new projection?
Thanks so much for the help!
-- john
