am I insane or is something broken?
nelson at crynwr.com
Sat Dec 18 05:03:02 CET 2004
Could somebody please take a look at these two files:
The first is a set of polygons enclosing school districts in my county.
The second is a pair of files describing a map of my county.
If I simply load them both, and then hit "Zoom to full map extent",
then the shapefile is drawn in the region of N44 W75, whereas the map,
being a UTM map, is drawn at the (near-)equivalent UTM coords of
Okay, obviously the shapefile is being mis-projected. I'll bring up
Map/Projection.... and select UTM Zone 18 for the shapefile. Hey! It
works! My data appears exactly where it should.
The trouble occurs whenever I want to do any redisplay of the data.
As soon as I do, Python gets the scale completely wrong, and starts
telling me about uncaught division-by-zero errors.
I threw in some debugging print statements, and
Thuban.Model.map.BoundingBox is confused. It's computing one
BoundingBox in the wrong projection, and then returning a BoundingBox
that makes no sense:
BoundingBox: (435168.0, 4875232.0, 537568.0, 4992032.0)
BoundingBox: [-75.860046999999994, 44.050399999999996, -74.525683000000001, 45.01585]
BoundingBox returning (-75.860046999999994, 44.050399999999996, 537568.0, 4992032.0)
The scale gets set too small: scale: 6.2099508879e-05
I also see this in the Thuban output:
Warning: <Thuban.Model.map.Map instance at 0xf68649ec>.MAP_PROJECTION_CHANGED: <bound method MapCanvas.map_projection_changed of <Thuban.UI.view.MapCanvas instance; proxy of C++ wxWindow instance at _8923120_wxWindow_p>>()
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