WCExtension.h

Go to the documentation of this file.

// # WCExtension.h: Make the extension an image region
// # Copyright (C) 1998,2001
// # Associated Universities, Inc. Washington DC, USA.
// #
// # This library is free software; you can redistribute it and/or modify it
// # under the terms of the GNU Library General Public License as published by
// # the Free Software Foundation; either version 2 of the License, or (at your
// # option) any later version.
// #
// # This library is distributed in the hope that it will be useful, but WITHOUT
// # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
// # FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
// # License for more details.
// #
// # You should have received a copy of the GNU Library General Public License
// # along with this library; if not, write to the Free Software Foundation,
// # Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA.
// #
// # Correspondence concerning AIPS++ should be addressed as follows:
// #        Internet email: casa-feedback@nrao.edu.
// #        Postal address: AIPS++ Project Office
// #                        National Radio Astronomy Observatory
// #                        520 Edgemont Road
// #                        Charlottesville, VA 22903-2475 USA
 
#ifndef IMAGES_WCEXTENSION_H
#define IMAGES_WCEXTENSION_H
 
// # Includes
#include <casacore/casa/aips.h>
#include <casacore/images/Regions/WCCompound.h>
#include <casacore/casa/Arrays/IPosition.h>
 
namespace casacore {  // # NAMESPACE CASACORE - BEGIN
 
// # Forward declarations
class WCBox;
 
// <summary>
// Make the extension of an image region.
// </summary>
 
// <use visibility=export>
 
// <reviewed reviewer="" date="" tests="">
// </reviewed>
 
// <prerequisite>
//   <li> <linkto class=WCCompound>WCCompound</linkto>
// </prerequisite>
 
// <synopsis>
// The WCExtension class is a specialization of class
// <linkto class=WCCompound>WCCompound</linkto>.
// It makes it possible to extend a region along straight lines to
// other dimensions. It is also possible to extend existing axes with
// length 1, i.e. to stretch such axes.
// E.g. a circle in the RA,DEC plane can be extended to
// a cylinder in a RA,DEC,FREQ cube. It is possible to extend over
// more than one dimension. One can also limit the extension range
// E.g. in the forementioned example the circle can be extended
// for a given range of frequencies only.
// <br>The extension axes and ranges have to be given as a
// <linkto class=WCBox>WCBox</linkto> object. The axes which are part
// of the box and the region are the axes to be stretched. Box axes
// which are not part of the region are the extension axes.
// <p>
// Note that regions get automatically extended when a region is used
// for a higher dimensioned image. The extension is done for all
// unknown axes (for their entire length).
// </synopsis>
 
// <example>
// <srcblock>
// </srcblock>
// </example>
 
// # <todo asof="1997/11/11">
// # <li>
// # </todo>
 
class WCExtension : public WCCompound {
 public:
  // Construct the extension of an image region using the axes
  // and blc,trc given in the extendBox.
  // The axes in region and box have to be disjoint.
  WCExtension(const ImageRegion& region, const WCBox& extendBox);
 
  // Copy constructor (copy semantics).
  WCExtension(const WCExtension& other);
 
  virtual ~WCExtension();
 
  // Assignment (copy semantics).
  WCExtension& operator=(const WCExtension& other);
 
  // Comparison
  virtual Bool operator==(const WCRegion& other) const;
 
  // Make a copy of the derived object.
  virtual WCRegion* cloneRegion() const;
 
  // Get the class name (to store in the record).
  static String className();
 
  // Get the region type.  Returns className()
  virtual String type() const;
 
  // Convert the (derived) object to a record.
  virtual TableRecord toRecord(const String& tableName) const;
 
  // Convert correct object from a record.
  static WCExtension* fromRecord(const TableRecord&, const String& tableName);
 
 protected:
  // WCExtension can extend a region if WCBox can do so.
  virtual Bool canExtend() const;
 
  // Convert to an LCRegion using the given coordinate system and shape.
  // pixelAxesMap(i) gives the pixel axis in cSys of axes <src>i</src>
  // in the axesDesc.
  virtual LCRegion* doToLCRegion(const CoordinateSystem& cSys, const IPosition& shape,
                                 const IPosition& pixelAxesMap, const IPosition& outOrder) const;
 
 private:
  // Construct from multiple regions given as a Block.
  // When <src>takeOver</src> is True, the destructor will delete the
  // given regions. Otherwise a copy of the regions is made.
  WCExtension(Bool takeOver, const Block<const WCRegion*>& regions);
 
  // Find the axes to be extended and stretched.
  // The extend axes are the axis numbers in the box.
  // For the stretch axes both box and region axes are returned.
  void findAxes(IPosition& extendBoxAxes, IPosition& stretchBoxAxes,
                IPosition& stretchRegionAxes) const;
};
 
}  // namespace casacore
 
#endif