[udig-devel] First (of many) reproject question

[Jody Garnett <jgarnett@xxxxxxxxxxxxxxx>]

Hi CRS guys I have a question / testcase for you ... the code is at the 
end of this message.

In short I am getting very different results from the Postgis 
transformation code - I am sure we went over this
back in the spring. I recall at the end of the day we got both systems 
returning with in 10cm of each other so
I am probably doing something wrong. The epsg.properties file being used 
was generated from PostGIS so
the WKT definitions they are working from should be identical.

Now the answer may be one of:
0) I messed up
1) Switch over to the CRS system
2) The old CS objects no longer work, or parse WKT differently
4) The epsg.properties file is some how wrong

If I messed up on this one I really would like to fix things as soon as 
possible because all DataStores, Lite renderer and UDIG
are funneling through the CRSService API.  It may be that CRSService 
wants to go and live next to all the other CRS code,
it operates as a Facade for that module after all....

Jody Garnett

------------------------
   public void testTranform() throws Exception {
       CoordinateSystem bc = service.createCoordinateSystem("EPSG:42102");
       CoordinateSystem latlong = 
service.createCoordinateSystem("EPSG:4269");
      
       MathTransform transform = CRSService.reproject( bc, latlong, true );
      
       // origional bc alberts
       Polygon poly1 = poly( new double[] {
               1187128,395268, 1187128,396027,
               1188245,396027, 1188245,395268,
               1187128,395268} );

       // transformed
       Polygon poly2 = poly( new double[] {
               -123.470095558323,48.5432615620081, 
-123.469728946766,48.5500959221152,
               -123.454638288508,48.5497352036088, 
-123.455007082796,48.5429008916377,
               -123.470095558323,48.5432615620081} );       
      
       Polygon polyAfter = CRSService.transform( poly1, transform );
       System.out.println( "expected:"+ polyAfter );
       System.out.println( "expected:"+ poly2 );       
       //assertEquals( poly2, polyAfter );
      
       Envelope before = poly1.getEnvelopeInternal();
       Envelope after = CRSService.transform( before, transform );
       assertEquals( poly2.getEnvelopeInternal(), after );       
   }
----------------------
Here is the output:
 actual:POLYGON ((-123.47009555832284 48.54326156200811, 
-123.46972894676578 48.55009592211517, -123.45463828850829 
48.54973520360885, -123.4550070827961 48.54290089163769, 
-123.47009555832284 48.54326156200811))
expected:POLYGON ((-123.470095558323 48.5432615620081, -123.469728946766 
48.5500959221152, -123.454638288508 48.5497352036088, -123.455007082796 
48.5429008916377, -123.470095558323 48.5432615620081))

 actual:Env[-138.4474639892578 : -138.4474639892578, 44.199676513671875 
: 44.199676513671875]
expected:Env[-123.470095558323 : -123.454638288508, 48.5429008916377 : 
48.5500959221152]