/** Tests axis swapping using {@link GeneralMatrix}. */
@Test
public void testAxisSwapping() {
AxisDirection[] srcAxis = {NORTH, EAST, UP};
AxisDirection[] dstAxis = {NORTH, EAST, UP};
GeneralMatrix matrix = new GeneralMatrix(srcAxis, dstAxis);
assertTrue(matrix.isAffine());
assertTrue(matrix.isIdentity());
dstAxis = new AxisDirection[] {WEST, UP, SOUTH};
matrix = new GeneralMatrix(srcAxis, dstAxis);
assertTrue(matrix.isAffine());
assertFalse(matrix.isIdentity());
assertEquals(
new GeneralMatrix(
new double[][] {
{0, -1, 0, 0},
{0, 0, 1, 0},
{-1, 0, 0, 0},
{0, 0, 0, 1}
}),
matrix);
dstAxis = new AxisDirection[] {DOWN, NORTH};
matrix = new GeneralMatrix(srcAxis, dstAxis);
assertFalse(matrix.isIdentity());
assertEquals(
new GeneralMatrix(
new double[][] {
{0, 0, -1, 0},
{1, 0, 0, 0},
{0, 0, 0, 1}
}),
matrix);
dstAxis = new AxisDirection[] {DOWN, DOWN};
matrix = new GeneralMatrix(srcAxis, dstAxis);
assertFalse(matrix.isIdentity());
assertEquals(
new GeneralMatrix(
new double[][] {
{0, 0, -1, 0},
{0, 0, -1, 0},
{0, 0, 0, 1}
}),
matrix);
dstAxis = new AxisDirection[] {DOWN, GEOCENTRIC_X};
try {
matrix = new GeneralMatrix(srcAxis, dstAxis);
fail();
} catch (IllegalArgumentException exception) {
// This is the expected exception (axis not in source).
}
srcAxis = dstAxis;
dstAxis = new AxisDirection[] {NORTH, EAST, UP, WEST};
try {
matrix = new GeneralMatrix(srcAxis, dstAxis);
fail();
} catch (IllegalArgumentException exception) {
// This is the expected exception (colinear axis).
}
}
/** Tests matrix inversion and multiplication using {@link Matrix2}. */
@Test
public void testMatrix2() {
final Matrix2 m = new Matrix2();
assertTrue(m.isAffine());
assertTrue(m.isIdentity());
final Random random = new Random(8447482612423035360L);
final GeneralMatrix identity = new GeneralMatrix(2);
for (int i = 0; i < 100; i++) {
m.setElement(0, 0, 100 * random.nextDouble());
m.setElement(0, 1, 100 * random.nextDouble());
m.setElement(1, 0, 100 * random.nextDouble());
m.setElement(1, 1, 100 * random.nextDouble());
final Matrix2 original = m.clone();
final GeneralMatrix check = new GeneralMatrix(m);
m.invert();
check.invert();
assertTrue(check.equals(m, 1E-9));
m.multiply(original);
assertTrue(identity.equals(m, 1E-9));
}
}
/*
* Copied from GeoTools GeoTiffMetadata2CRSAdapter because the given tie-point offset is
* not correctly interpreted in GeoTools. The tie-point should be placed at the pixel center
* if RasterPixelIsPoint is set as value for GTRasterTypeGeoKey.
* See links:
* http://www.remotesensing.org/geotiff/faq.html#PixelIsPoint
* http://lists.osgeo.org/pipermail/gdal-dev/2007-November/015040.html
* http://trac.osgeo.org/gdal/wiki/rfc33_gtiff_pixelispoint
*/
private static MathTransform getRasterToModel(final GeoTiffIIOMetadataDecoder metadata)
throws GeoTiffException {
//
// Load initials
//
final boolean hasTiePoints = metadata.hasTiePoints();
final boolean hasPixelScales = metadata.hasPixelScales();
final boolean hasModelTransformation = metadata.hasModelTrasformation();
int rasterType = getGeoKeyAsInt(GeoTiffConstants.GTRasterTypeGeoKey, metadata);
// geotiff spec says that PixelIsArea is the default
if (rasterType == GeoTiffConstants.UNDEFINED) {
rasterType = GeoTiffConstants.RasterPixelIsArea;
}
MathTransform xform;
if (hasTiePoints && hasPixelScales) {
//
// we use tie points and pixel scales to build the grid to world
//
// model space
final TiePoint[] tiePoints = metadata.getModelTiePoints();
final PixelScale pixScales = metadata.getModelPixelScales();
// here is the matrix we need to build
final GeneralMatrix gm = new GeneralMatrix(3);
final double scaleRaster2ModelLongitude = pixScales.getScaleX();
final double scaleRaster2ModelLatitude = -pixScales.getScaleY();
// "raster" space
final double tiePointColumn =
tiePoints[0].getValueAt(0)
+ (rasterType == GeoTiffConstants.RasterPixelIsPoint ? 0.5 : 0);
final double tiePointRow =
tiePoints[0].getValueAt(1)
+ (rasterType == GeoTiffConstants.RasterPixelIsPoint ? 0.5 : 0);
// compute an "offset and scale" matrix
gm.setElement(0, 0, scaleRaster2ModelLongitude);
gm.setElement(1, 1, scaleRaster2ModelLatitude);
gm.setElement(0, 1, 0);
gm.setElement(1, 0, 0);
gm.setElement(
0, 2, tiePoints[0].getValueAt(3) - (scaleRaster2ModelLongitude * tiePointColumn));
gm.setElement(1, 2, tiePoints[0].getValueAt(4) - (scaleRaster2ModelLatitude * tiePointRow));
// make it a LinearTransform
xform = ProjectiveTransform.create(gm);
} else if (hasModelTransformation) {
if (rasterType == GeoTiffConstants.RasterPixelIsPoint) {
final AffineTransform tempTransform =
new AffineTransform(metadata.getModelTransformation());
tempTransform.concatenate(AffineTransform.getTranslateInstance(0.5, 0.5));
xform = ProjectiveTransform.create(tempTransform);
} else {
assert rasterType == GeoTiffConstants.RasterPixelIsArea;
xform = ProjectiveTransform.create(metadata.getModelTransformation());
}
} else {
throw new GeoTiffException(metadata, "Unknown Raster to Model configuration.", null);
}
return xform;
}