[
Date Prev][
Date Next][
Thread Prev][
Thread Next][
Date Index][
Thread Index]
[
List Home]
|
[udig-devel] Re: EPSG-ACCESS and EPS-WKT
|
simone giannecchini a écrit :
1>Is it my impression or the Standard Mercator 1 parallel projection
is not yeat supported in GeoTools? I think this since I get no errors
or exception but nothing happens.
Mercator 1 parallel projection is supported in Geotools. If a projection
is not supported, you should get an exception.
In the particular case of Mercator projection, one may get the illusion
that nothing is done. This is because that at the difference of Conic or
Stereographic projection (for example), the Cylindical Mercator
projection keep parallels and meridians as straight lines crossing at
right angles. The only visible difference compared to a plain
latitude/longitude map is that parallels close to the poles are further
apart. See:
http://mathworld.wolfram.com/MercatorProjection.html
There is many way you can check if a projection has really be done:
- Print GridCoverage2D.getEnvelope() and check the coordinates.
- Invoke GridCoverage2D.getRenderedImage() and inspect the JAI
operations. You can do that graphically using the
org.geotools.gui.swing.ImageProperties widget (I invite you to
try this widget; it is of some help for debugging image processing).
2>Are epsg-access and epsg-wkt interchangeable?
epsg
[...snip...]
AXIS["Geodetic latitude", NORTH, AUTHORITY["EPSG","106"]],
AXIS["Geodetic longitude", EAST, AUTHORITY["EPSG","107"]],
wkt
[...snip...]
AXIS["Lon", EAST],
AXIS["Lat", NORTH],
I checked in the EPSG database version 6.6, and the correct axis order
is the one produced by EPSG-Access.
This explain the problems we have been experiencing in the WMS-WCS
side because of the fact that we were using epsg-access and epsg-wkt
at the same time.
Right. So we have a choice:
1) Either someone fix the EPSG WKT property file.
or 2) A volunter go ahead and do GEOT-46, which could be a replacement
for the WKT factory. See http://jira.codehaus.org/browse/GEOT-46
Martin.
