Geometry.h

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//# Copyright (C) 2010 by ESO (in the framework of the ALMA collaboration)
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#ifndef SCIMATH_GEOMETRY_H
#define SCIMATH_GEOMETRY_H
 
#include <casacore/casa/aips.h>
#include <casacore/casa/Quanta/Quantum.h>
#include <utility>
 
namespace casacore { //# NAMESPACE CASACORE - BEGIN
 
// <summary>
// Geometry related methods.
// </summary>
 
// <use visibility=export>
 
//# <author>Dave Mehringer</author>
// <reviewed reviewer="" date="yyyy/mm/dd" tests="" demos="">
// </reviewed>
// <etymology>
// self-explanatory
// </etymology>
 
// <synopsis>
// Various geometry related functions
// </synopsis>
 
// <motivation>
// Commonly used geometrical functions for various image and region
// applications.
// </motivation>
 
class Geometry {
  
public:
 
    // Get result of rotating a 2-D vector counterclockwise through an angle
    // <src>theta</src>. The output pair will have x as the first
    // member and y as the second. <src>theta</src> must have angular units (no explicit
    // checking is done, but an exception will be thrown from the Quanta code if not).
    static std::pair<Double, Double> rotate2D(
        Double x, Double y, const Quantity& theta
    );
 
    // Determine if two coplanar line segments, a and b, intersect. Line segment a
    // has end points a0 and a1, and line segment b has endpoints b0 and b1.
    // Algorithm from
    // http://stackoverflow.com/questions/563198/how-do-you-detect-where-two-line-segments-intersect
    static Bool doLineSegmentsIntersect(
        Double a0x, Double a0y, Double a1x, Double a1y,
        Double b0x, Double b0y, Double b1x, Double b1y
    );
 
};
} //# NAMESPACE CASACORE - END
 
#endif