plane.h

/*  Renegade Scripts.dll
    Copyright 2013 Tiberian Technologies
 
    This file is part of the Renegade scripts.dll
    The Renegade scripts.dll is free software; you can redistribute it and/or modify it under
    the terms of the GNU General Public License as published by the Free
    Software Foundation; either version 2, or (at your option) any later
    version. See the file COPYING for more details.
    In addition, an exemption is given to allow Run Time Dynamic Linking of this code with any closed source module that does not contain code covered by this licence.
    Only the source code to the module(s) containing the licenced code has to be released.
*/
#ifndef _MATH_PLANE_H_
#define _MATH_PLANE_H_
 
#include "Vector3.h"
#include "SphereClass.h"
class PlaneClass
{
public:
    Vector3 N;
    float D;
 
    PlaneClass() : N(0.0f, 0.0f, 1.0f), D(0.0f) {};
 
    PlaneClass(float nx, float ny, float nz, float dist)
    {
        Set(nx, ny, nz, dist);
    };
 
    PlaneClass(const Vector3& normal, float dist)
    {
        Set(normal, dist);
    };
 
    PlaneClass(const Vector3& normal, const Vector3& point)
    {
        Set(normal, point);
    };
 
    PlaneClass(const Vector3& point1, const Vector3& point2, const Vector3& point3)
    {
        Set(point1, point2, point3);
    };
 
    inline void Set(float a, float b, float c, float d)
    {
        N.X = a;
        N.Y = b;
        N.Z = c;
        D = d;
    };
 
    inline void Set(const Vector3& normal, float dist)
    {
        N = normal;
        D = dist;
    };
 
    inline void Set(const Vector3& normal, const Vector3& point)
    {
        N = normal;
        D = Vector3::Dot_Product(normal, point);
    };
 
    inline void Set(const Vector3& point1, const Vector3& point2, const Vector3& point3) 
    {
        N = Vector3::Cross_Product((point2 - point1), (point3 - point1));
        if (N != Vector3(0.0f, 0.0f, 0.0f)) {
            // Points are not colinear. Normalize N and calculate D.
            N.Normalize();
            D = N * point1;
        } else {
            // They are colinear - return default plane (constructors can't fail).
            N = Vector3(0.0f, 0.0f, 1.0f);
            D = 0.0f;
        }
    }
 
    inline void Normalize()
    {
        float oolength = 1.0f / N.Length();
        N *= oolength;
        D *= oolength;
    }
 
    inline PlaneClass operator - ()
    {
        return PlaneClass(-N, D);
    }
    bool In_Front(const Vector3 & point) const;
    bool In_Front(const SphereClass & sphere) const;
    bool Compute_Intersection(const Vector3 & p0,const Vector3 & p1,float * set_t) const;
};
inline bool PlaneClass::In_Front(const Vector3 & point) const
{
    float dist = Vector3::Dot_Product(point,N);
    return (dist > D);
}
inline bool PlaneClass::In_Front(const SphereClass & sphere) const
{
    float dist = Vector3::Dot_Product(sphere.Center,N);
    return ((dist - D) >= sphere.Radius);
}
inline bool PlaneClass::Compute_Intersection(const Vector3 & p0,const Vector3 & p1,float * set_t) const
{
    float num,den;
    den = Vector3::Dot_Product(N,p1-p0);
    if (den == 0.0f)
    {
        return false;
    }
    num = -(Vector3::Dot_Product(N,p0) - D);
    *set_t = num/den;
    if ((*set_t < 0.0f) || (*set_t > 1.0f))
    {
        return false;
    }
    return true;
}
#endif