Hi uDiggers,

In my day job (mapping pacific salmon habitat, rivers, and ecosystems) I am constantly projecting spatial data in custom projections that place the central meridian in the center of the Pacific Ocean (180 longitude). This works perfectly to stitch together the North Pacific region of my focus, but tends to produce anomalies when switching software apps. For example, I get the error "Problem rendering: Latitude 90 degrees N is too close to a pole" when I add my data as a layer in uDig.

I have been following the efforts to make relative paths work, and therefore to be able to package uDig as a data viewer on a CD. This is a feature I'm excited about but this projection issue would hold me up. So, I'd be interested if anyone wants to take a crack at either explaining to me what it would take to get my custom projection to work in uDig or to detail if there is custom projection functionality that I am not aware of.

I have posted an example dataset here:

http://danespringmeyer.com/north_pacific_watersheds.zip

it is a hack of the standard world mercator projection:

PROJCS["Clarke_1866_Mercator",GEOGCS["GCS_Clarke_1866",DATUM ["D_Clarke_1866",SPHEROID["Clarke_1866",6378206.4,294.9786982]],PRIMEM ["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION ["Mercator"],PARAMETER["False_Easting",0.0],PARAMETER ["False_Northing",0.0],PARAMETER["Central_Meridian",180.0],PARAMETER ["Standard_Parallel_1",47.5],UNIT["Meter",1.0]]


Cheers,

Dane




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