ElevationModel.h

/**********************************************************************
 *
 * GEOS - Geometry Engine Open Source
 * http://geos.osgeo.org
 *
 * Copyright (C) 2020 Sandro Santilli <strk@kbt.io>
 *
 * This is free software; you can redistribute and/or modify it under
 * the terms of the GNU Lesser General Public Licence as published
 * by the Free Software Foundation.
 * See the COPYING file for more information.
 *
 **********************************************************************
 *
 * Last Port: operation/overlayng/ElevationModel.java 4c88fea52
 *
 **********************************************************************/
 
#pragma once
 
#include <geos/export.h>
 
#include <geos/geom/Envelope.h> // for composition
 
// Forward declarations
namespace geos {
    namespace geom {
        class Geometry;
    }
}
 
namespace geos {      // geos.
namespace operation { // geos.operation
namespace overlayng { // geos.operation.overlayng
 
 
class GEOS_DLL ElevationModel {
 
private:
 
    class ElevationCell {
    private:
 
      int numZ = 0;
      double sumZ = 0.0;
      double avgZ;
 
    public:
 
      bool isNull() const
      {
        return numZ == 0;
      }
 
      void add(double z)
      {
        ++numZ;
        sumZ += z;
      }
 
      void compute()
      {
        avgZ = DoubleNotANumber;
        if (numZ > 0)
          avgZ = sumZ / numZ;
      }
 
      double getZ() const
      {
        return avgZ;
      }
    };
 
 
    static const int DEFAULT_CELL_NUM;
    geom::Envelope extent;
    int numCellX;
    int numCellY;
    double cellSizeX;
    double cellSizeY;
    std::vector<ElevationCell> cells;
    bool isInitialized = false;
    bool hasZValue = false;
    double averageZ = DoubleNotANumber;
 
    void init();
 
    ElevationCell& getCell(double x, double y); //, bool isCreateIfMissing);
 
    int getCellOffset(int ix, int iy) {
        return (numCellX * iy + ix);
    }
 
protected:
 
  void add(double x, double y, double z);
 
 
public:
 
    static std::unique_ptr<ElevationModel> create(const geom::Geometry& geom1,
                                                const geom::Geometry& geom2);
 
    static std::unique_ptr<ElevationModel> create(const geom::Geometry& geom1);
 
    ElevationModel(const geom::Envelope& extent, int numCellX, int numCellY);
 
    void add(const geom::Geometry& geom);
 
 
    double getZ(double x, double y);
 
 
    void populateZ(geom::Geometry& geom);
 
 
};
 
} // namespace geos.operation.overlayng
} // namespace geos.operation
} // namespace geos