Geometry.h

#ifndef GEOMETRY_
#define GEOMETRY_

#include <math.h>

#define MY_PI                                   3.141592f

typedef struct AABoundingBox
{
        float xmin;                             
        float xmax;                             
        float ymin;                             
        float ymax;                             
        float zmin;                             
        float zmax;                             
}BoundingBox;

typedef struct Point3D
{
        float x;                                
        float y;                                
        float z;                                
}Vector, Point;

typedef struct BoundingBoxCorners
{
        Point p[8];                             
}BoxCorners;

typedef struct Plane3D
{
        Vector n;                               
        float d;                                
}Plane;

class Geometry
{
public:

        static Point PlaneIntersection (const Plane& p1, const Plane& p2, const Plane& p3);

        static void InvertHomogenousMatrix (double * src, double * dest);

        static void InvertHomogenousMatrix (float * src, float * dest);

        static void MatrixMultiply (double * m1, double * m2, double * dest);

        static void VectorMultiply (float * m, const Vector & vect, Vector & res);

        static void VectorNormalize (Vector & vect);

        static float VectorLength (Vector & vect);

        static float EnclosingAngle (Vector & v1, Vector & v2);

        static Vector CrossProduct (const Vector& v1, const Vector& v2);

        static float ScalarProduct (const Vector &v1, const Vector &v2);

private:
        Geometry ();
};

#endif

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