Re: [Geotools-gt2-users] Getting world coordinates by Mouseclick, Mousebehaviour on StyledMapPane

[Martin D. <mar...@no...>]

Martin Schmitz a =E9crit :
> In the vertical direction everything is exactly correct. The problem is=
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> the horizontal.
>=20
> As I found out just a minute ago, the reason seems not to be the method=
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> GeoMouseEvent.getMapCoordinate(.) because if I move the cursor in the=20
> lower left corner, it returns the correct lat/lon position of my raster=
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> So the problem must be GridCoverage.evaluate(Point2D,.).
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> Is there a bug in the transformation from the lat/lon to raster=20
> coordinates? Rounding problems?

Not as far as I know. It seems to work correctly on my own software (but=20
I may be wrong - more tests would be better). There is no separated=20
processing for the horizontal and the vertical axis. Most=20
transformations are handled by java.awt.geom.AffineTransform, which=20
handle both axis simultaneously. An error may occurs while setting up=20
the AffineTransform however. I suggest to try the following:

  MathTransform tr =3D=20
gridCoverage.getGridGeometry().getGridToCoordinateSystem();
  System.out.println(tr);

Make sure that the affine transform coefficients are the expected one.

The AffineTransform can be setup by GridCoverage2D at construction time=20
from the image size and an user-supplied Envelope. Make sure that the=20
envelope is correct. If the envelope is correct but GridCoverage2D setup=20
an incorrect AffineTransform, please let me know.

	Martin.