mymath.h

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#ifndef mymath_h
#define mymath_h

#include <OS/math.h>
#include <InterViews/geometry.h>

extern "C" int nrn_isdouble(double*, double, double);

class Extension;

class MyMath {
public:
    // increase all around in screen coords
    static void extend(Extension&, Coord);
    static void extend(Extension&, const Extension&);
    
    static void minmax(Coord& min, Coord& max);
    static bool inside(Coord x, Coord min, Coord max);

    static float min(int count, const float*);
    static float max(int count, const float*);
    
    static bool inside(
        Coord x, Coord y,
        Coord left, Coord bottom, Coord right, Coord top
    );

    // within epsilon distance from the infinite line
    static bool near_line(
        Coord x, Coord y,
        Coord x1, Coord y1, Coord x2, Coord y2,
        float epsilon
    );

    // within epsilon distance from the line segment
    static bool near_line_segment(
        Coord x, Coord y,
        Coord x1, Coord y1, Coord x2, Coord y2,
        float epsilon
    );

    // returns distance between point and line segment
    static float distance_to_line_segment(
        Coord x, Coord y,
        Coord x1, Coord y1, Coord x2, Coord y2
    );

    // returns distance between point and line
    static float distance_to_line(
        Coord x, Coord y,
        Coord x1, Coord y1, Coord x2, Coord y2
    );

    
    // returns square norm
    static float norm2(Coord x, Coord y) {
        return x*x + y*y;
    }

    // unit length vector perpindicular to vector (x, y)
    static bool unit_normal(Coord x, Coord y, Coord* perp);
    
    // returns range extended to nearest 1.5 digit accuracy.
    // ie. digit is 1, 2, or 5
    static void round_range(Coord x1, Coord x2, double& y1, double& y2,
        int& ntic);
    static void round_range_down(Coord x1, Coord x2, double& y1, double& y2,
        int& ntic);

    enum {Expand, Contract, Higher, Lower};
    static double round(float& x1, float& x2, int direction, int digits);
     
    static void box(Requisition&, Coord& x1, Coord& y1, Coord& x2, Coord& y2);

    static double anint(double); /* round toward nearest integer */
    static double resolution(double); // 100, 10, .1,... least significant digit

    static bool lt(double x, double y, double e) { return x < (y-e); }
    static bool le(double x, double y, double e) { return x <= (y+e); }
    static bool eq(double x, double y, double e) { return Math::equal(x,y,e);}
    static bool eq2(double x, double y, double e) { return x - y <= e && y - x <= e; }
};

inline void MyMath::extend(Extension& e, const Extension& x) {
    e.set_xy(NULL, e.left() + x.left(), e.bottom() + x.bottom(),
        e.right() + x.right(), e.top() + x.top());
}

inline void MyMath::extend(Extension& e, Coord x) {
    e.set_xy(NULL, e.left() - x, e.bottom() - x, e.right() + x, e.top() + x);
}

inline void MyMath::minmax(Coord& x, Coord& y) {
    if (y < x) {Coord z = x; x = y; y = z;}
}

inline bool MyMath::inside(Coord x, Coord x1, Coord x2) {
    return (x >= x1 && x <= x2);
}

inline bool MyMath::inside(Coord x, Coord y, Coord x1, Coord y1, Coord x2, Coord y2) {
    return inside(x, x1, x2) && inside(y, y1, y2);
}

#endif