DemShape.h

#ifndef DemShape_h
#define DemShape_h
 
/* SPDX-License-Identifier: CC0-1.0 */
 
#include "ShapeModel.h"
 
namespace Isis {
  class Cube;
  class Interpolator;
  class Portal;
  class Projection;

  class DemShape : public ShapeModel {
    public:
      // Constructor
      DemShape(Target *target, Pvl &pvl);
 
      // Constructor
      DemShape();
 
      // Destructor
      ~DemShape();
 
      // Make parent functions visible
      using Isis::ShapeModel::intersectSurface;
 
      // Intersect the shape model
      bool intersectSurface(std::vector<double> observerPos,
                            std::vector<double> lookDirection);
 
      Distance localRadius(const Latitude &lat, const Longitude &lon);
 
      // Return dem scale in pixels/degree
      double demScale();
 
      // implement pure virtual method from ShapeModel class
      bool isDEM() const;
 
      // To compute the surface normal, you must call setLocalAreaPoint on top,
      // bottom, left, and right surrounding points in the image.  Then call
      // calculateSurfaceNormal and directSurfaceNormal to calculate the normal.
      // Use removeLOcalAreaPoints to clean up as needed.  See Camera for an
      // example, or use its GetLocalNormal method.
 
      // Calculate the surface normal of the current intersection point
     void calculateLocalNormal(QVector<double *> cornerNeighborPoints);
 
    protected:
      Cube *demCube();         
 
    private:
    
      // Given a position along a ray, compute the difference between the radius
      // at that position and the surface radius at that lon-lat location.
      // Update the intersection point in the class based on the input
      // parameters. All lengths are in km.
      double calcDemErrUpdateIntersection(std::vector<double> const& observerPos,
                                          std::vector<double> const& lookDirection, 
                                          double t, 
                                          double * intersectionPoint,
                                          bool & success);
    
      // Find a value in the DEM. Used when intersecting a ray with the DEM.
      // Returned value is in km. 
      double findDemValue();
      
      Cube *m_demCube;        
      Projection *m_demProj;  
      double m_pixPerDegree;  
      Portal *m_portal;       
      Interpolator *m_interp; 
      double m_demValue;      
      bool m_demValueFound;   
  };
}
 
#endif