visibility.h

#pragma once
#include "viewshed_export.h"
 
#include "constants.h"
#include "enums.h"
 
using viewshed::CellEventPositionType;
 
namespace viewshed
{
    class Point;
    class RasterPosition;
    class CellEventPosition;

    class DLL_API Visibility
    {
      public:
        static double distance( const double &x1, const double &y1, const double &x2, const double &y2,
                                const double &cellSize );

        static double gradient( double elevationDiff, double distance );

        static double curvatureCorrections( const double &distance, const double &refractionCoeff,
                                            const double &earthDiameter );

        static double curvatureCorrections( double &distance )
        {
            return curvatureCorrections( distance, viewshed::REFRACTION_COEFFICIENT, viewshed::EARTH_DIAMETER );
        };

        static CellEventPosition eventPosition( const CellEventPositionType &eventType, const int &row, const int &col,
                                                const int &pointRow, const int &pointCol );

        static double angle( const double &row, const double &column, const int &pointRow, const int &pointCol );
    };
} // namespace viewshed