/**
* Applies a crop operation to a coverage.
*
* @see
* org.geotools.coverage.processing.AbstractOperation#doOperation(org.opengis.parameter.ParameterValueGroup,
* org.geotools.factory.Hints)
*/
@SuppressWarnings("unchecked")
public Coverage doOperation(ParameterValueGroup parameters, Hints hints) {
final Geometry cropRoi; // extracted from parameters
GeneralEnvelope cropEnvelope = null; // extracted from parameters
final GridCoverage2D source; // extracted from parameters
final double roiTolerance = parameters.parameter(Crop.PARAMNAME_ROITOLERANCE).doubleValue();
final boolean forceMosaic = parameters.parameter(Crop.PARAMNAME_FORCEMOSAIC).booleanValue();
// /////////////////////////////////////////////////////////////////////
//
// Assigning and checking input parameters
//
// ///////////////////////////////////////////////////////////////////
// source coverage
final ParameterValue sourceParameter = parameters.parameter("Source");
if (sourceParameter == null || !(sourceParameter.getValue() instanceof GridCoverage2D)) {
throw new CannotCropException(
Errors.format(ErrorKeys.NULL_PARAMETER_$2, "Source", GridCoverage2D.class.toString()));
}
source = (GridCoverage2D) sourceParameter.getValue();
// Check Envelope and ROI existence - we need at least one of them
final ParameterValue envelopeParameter = parameters.parameter(PARAMNAME_ENVELOPE);
final ParameterValue roiParameter = parameters.parameter(PARAMNAME_ROI);
if ((envelopeParameter == null || envelopeParameter.getValue() == null)
&& (roiParameter == null || roiParameter.getValue() == null))
throw new CannotCropException(
Errors.format(
ErrorKeys.NULL_PARAMETER_$2, PARAMNAME_ENVELOPE, GeneralEnvelope.class.toString()));
Object envelope = envelopeParameter.getValue();
if (envelope != null) {
if (envelope instanceof GeneralEnvelope) {
cropEnvelope = (GeneralEnvelope) envelope;
} else if (envelope instanceof Envelope) {
cropEnvelope = new GeneralEnvelope((Envelope) envelope);
}
}
// may be null
// Check crop ROI
try {
cropRoi =
IntersectUtils.unrollGeometries(
(Geometry) roiParameter.getValue()); // may throw if format not correct
} catch (IllegalArgumentException ex) {
throw new CannotCropException(
Errors.format(ErrorKeys.ILLEGAL_ARGUMENT_$2, PARAMNAME_ROI, ex.getMessage()), ex);
}
// Setting a GeneralEnvelope from ROI if needed
if (cropRoi != null && cropEnvelope == null) {
Envelope e2d =
JTS.getEnvelope2D(cropRoi.getEnvelopeInternal(), source.getCoordinateReferenceSystem());
cropEnvelope = new GeneralEnvelope(e2d);
}
// /////////////////////////////////////////////////////////////////////
//
// Initialization
//
// We take the crop envelope and the source envelope then we check their
// crs and we also check if they ever overlap.
//
// /////////////////////////////////////////////////////////////////////
// envelope of the source coverage
final Envelope2D sourceEnvelope = source.getEnvelope2D();
// crop envelope
Envelope2D destinationEnvelope = new Envelope2D(cropEnvelope);
CoordinateReferenceSystem sourceCRS = sourceEnvelope.getCoordinateReferenceSystem();
CoordinateReferenceSystem destinationCRS = destinationEnvelope.getCoordinateReferenceSystem();
if (destinationCRS == null) {
// Do not change the user provided object - clone it first.
final Envelope2D ge = new Envelope2D(destinationEnvelope);
destinationCRS = source.getCoordinateReferenceSystem2D();
ge.setCoordinateReferenceSystem(destinationCRS);
destinationEnvelope = ge;
}
// //
//
// Source and destination crs must be equals
//
// //
if (!CRS.equalsIgnoreMetadata(sourceCRS, destinationCRS)) {
throw new CannotCropException(
Errors.format(
ErrorKeys.MISMATCHED_ENVELOPE_CRS_$2,
sourceCRS.getName().getCode(),
destinationCRS.getName().getCode()));
}
if (cropRoi != null) {
// TODO: check ROI SRID
}
// //
//
// Check the intersection and, if needed, do the crop operation.
//
// //
final GeneralEnvelope intersectionEnvelope =
new GeneralEnvelope((Envelope) destinationEnvelope);
intersectionEnvelope.setCoordinateReferenceSystem(source.getCoordinateReferenceSystem());
// intersect the envelopes
intersectionEnvelope.intersect(sourceEnvelope);
if (intersectionEnvelope.isEmpty())
throw new CannotCropException(Errors.format(ErrorKeys.CANT_CROP));
// intersect the ROI with the intersection envelope and throw an error if they do not intersect
if (cropRoi != null) {
final Geometry jis =
JTS.toGeometry(
(com.vividsolutions.jts.geom.Envelope) new ReferencedEnvelope(intersectionEnvelope));
if (!IntersectUtils.intersects(cropRoi, jis))
throw new CannotCropException(Errors.format(ErrorKeys.CANT_CROP));
}
// //
//
// Get the grid-to-world transform by keeping into account translation
// of grid geometry constructor for respecting OGC PIXEL-IS-CENTER
// ImageDatum assumption.
//
// //
final AffineTransform sourceCornerGridToWorld =
(AffineTransform)
((GridGeometry2D) source.getGridGeometry()).getGridToCRS(PixelInCell.CELL_CORNER);
// //
//
// I set the tolerance as half the scale factor of the grid-to-world
// transform. This should more or less means in most cases "don't bother
// to crop if the new envelope is as close to the old one that we go
// deep under pixel size."
//
// //
final double tolerance = XAffineTransform.getScale(sourceCornerGridToWorld);
if (cropRoi != null || !intersectionEnvelope.equals(sourceEnvelope, tolerance / 2.0, false)) {
cropEnvelope = intersectionEnvelope.clone();
return buildResult(
cropEnvelope,
cropRoi,
roiTolerance,
forceMosaic,
(hints instanceof Hints) ? (Hints) hints : new Hints(hints),
source,
sourceCornerGridToWorld);
} else {
// //
//
// Note that in case we don't crop at all, WE DO NOT UPDATE the
// envelope. If we did we might end up doing multiple successive
// crop without actually cropping the image but, still, we would
// shrink the envelope each time. Just think about having a loop
// that crops recursively the same coverage specifying each time an
// envelope whose URC is only a a scale quarter close to the LLC of
// the old one. We would never crop the raster but we would modify
// the grid-to-world transform each time.
//
// //
return source;
}
}
