genesis-3d_engine/Engine/foundation/math/newMath/new_plane.h

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Copyright (c) 2007, Radon Labs GmbH
Copyright (c) 2011-2013,WebJet Business Division,CYOU
 
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#pragma once
#include "core/types.h"
#include "math/scalar.h"
#include "math/float4.h"
#include "math/line.h"
#include "math/clipstatus.h"
//#include "math/float3.h"
//------------------------------------------------------------------------------
namespace Math
{
class matrix44;
class plane;
//class float3;

// win32 VC++ does not support passing aligned objects as value so far
// here is a bug-report at microsoft saying so:
// http://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=334581
typedef const plane& __PlaneArg;
 

class plane
{
public:
    /// default constructor, NOTE: does NOT setup componenets!
    plane();
    /// !!!! copy constructor forbidden, otherwise passing plane's to a function
    /// !!!! via Registers doesnt work
    //plane(const plane& rhs);
    /// construct from components
    plane(scalar a, scalar b, scalar c, scalar d);
    /// construct from points
    plane(const float4& p0, const float4& p1, const float4& p2);
    /// construct from point and normal
    plane(const float4& p, const float4& n);
    /// construct from Ogre::Vector4
	plane(Ogre::Vector4 rhs);

    /// setup from points
    void setup_from_points(const float4& point1, const float4& point2, const float4& point3);
    /// setup from point and normal
    void setup_from_point_and_normal(const float4& p, const float4& n);
    /// set componenets
    void set(scalar a, scalar b, scalar c, scalar d);
    /// set the x component
    void set_a(scalar a);
    /// set the y component
    void set_b(scalar b);
    /// set the z component
    void set_c(scalar c);
    /// set the w component
    void set_d(scalar d);

    /// read/write access to A component
    scalar& a();
    /// read/write access to B component
    scalar& b();
    /// read/write access to C component
    scalar& c();
    /// read/write access to D component
    scalar& d();
    /// read-only access to A component
    scalar a() const;
    /// read-only access to B component
    scalar b() const;
    /// read-only access to C component
    scalar c() const;
    /// read-only access to D component
    scalar d() const;

    /// compute dot product of plane and vector
    scalar dot(const float4& v) const;
    /// find intersection with line
    bool intersectline(const float4& startPoint, const float4& endPoint, float4& outIntersectPoint) const;
    /// clip line against this plane
    ClipStatus::Type clip(const line& l, line& outClippedLine) const;
    /// normalize plane components a,b,c

	/// distance to point
	float distance(const point& pl) const;

    static plane normalize(const plane& p);
    /// transform plane by inverse transpose of transform
#ifdef __VC__
	static __declspec(deprecated) plane transform( const matrix44& m, __PlaneArg p);
#else
	static plane transform( const matrix44& m, __PlaneArg p);
#endif
    

	Ogre::Vector4 vec;
private:
    friend class matrix44;

	
};

//------------------------------------------------------------------------------
/**
*/
inline
plane::plane()
{
    // empty
}

//------------------------------------------------------------------------------
/**
*/
inline
plane::plane(scalar a, scalar b, scalar c, scalar d)
{
    this->vec = Ogre::Vector4(a, b, c, d);
}

//------------------------------------------------------------------------------
/**
*/
inline
plane::plane(const float4& p0, const float4& p1, const float4& p2)
{
    this->setup_from_points(p0, p1, p2);
}

//------------------------------------------------------------------------------
/**
*/
inline
plane::plane(const float4& p0, const float4& n)
{
    this->setup_from_point_and_normal(p0, n);
}

//------------------------------------------------------------------------------
/**
*/
inline
plane::plane(Ogre::Vector4 rhs) :
    vec(rhs)
{
    // empty
}

//------------------------------------------------------------------------------
/**
*/
inline void
plane::setup_from_points(const float4& point1, const float4& point2, const float4& point3)
{
	//float4 Result;
	//Ogre::Vector3 N;
	//float4 D;

	//Ogre::Vector3 V21 = Ogre::Vector3(p0.x(),p0.y(),p0.z()) - Ogre::Vector3(p1.x(),p1.y(),p1.z());
	//Ogre::Vector3 V31 = Ogre::Vector3(p0.x(),p0.y(),p0.z()) - Ogre::Vector3(p2.x(),p2.y(),p2.z());

	//N = V21.crossProduct(V31);
	//N = N.normalise();

	////D = XMPlaneDotNormal(N, p1);
	//D.set_x(N.dotProduct(Ogre::Vector3(p1.x(),p1.y(),p1.z())));
	//D.set_y(N.dotProduct(Ogre::Vector3(p1.x(),p1.y(),p1.z())));
	//D.set_z(N.dotProduct(Ogre::Vector3(p1.x(),p1.y(),p1.z())));
	//D.set_w(N.dotProduct(Ogre::Vector3(p1.x(),p1.y(),p1.z())));
	//Result.set_x(N.x);
	//Result.set_y(N.y);
	//Result.set_z(N.z);
	//Result.set_w(-D.w());


	//this->vec = Result.vec;
 //   //this->vec = XMPlaneFromPoints(p0.vec, p1.vec, p2.vec);

	float num10 = point2.x() - point1.x();
	float num9 = point2.y() - point1.y();
	float num8 = point2.z() - point1.z();
	float num7 = point3.x() - point1.x();
	float num6 = point3.y() - point1.y();
	float num5 = point3.z() - point1.z();
	float num4 = (num9 * num5) - (num8 * num6);
	float num3 = (num8 * num7) - (num10 * num5);
	float num2 = (num10 * num6) - (num9 * num7);
	float num11 = ((num4 * num4) + (num3 * num3)) + (num2 * num2);
	float num = 1.0f / n_sqrt(num11);
	this->vec.x = num4 * num;
	this->vec.y = num3 * num;
	this->vec.z = num2 * num;
	this->vec.w = -(this->vec.x * point1.x() + this->vec.y * point1.y() + this->vec.z * point1.z());


}

//------------------------------------------------------------------------------
/**
*/
inline void
plane::setup_from_point_and_normal(const float4& p, const float4& n)
{
	float4 Result(0.0f,0.0f,0.0f,0.0f);

	Result.set_x(n.x());
	Result.set_y(n.y());
	Result.set_z(n.z());
	float temp = p.x() * n.x() + p.y() * n.y() + p.z() * n.z();
	Result.set_w(-temp);

	this->vec = Result.vec;
}

//------------------------------------------------------------------------------
/**
*/
inline void
plane::set(scalar a, scalar b, scalar c, scalar d)
{
    this->vec = Ogre::Vector4(a, b, c, d);
}

//------------------------------------------------------------------------------
/**
*/
inline scalar&
plane::a()
{
    return this->vec.x;
}

//------------------------------------------------------------------------------
/**
*/
inline scalar
plane::a() const
{
    return this->vec.x;
}

//------------------------------------------------------------------------------
/**
*/
inline scalar&
plane::b()
{
    return this->vec.y;

}

//------------------------------------------------------------------------------
/**
*/ 
inline scalar
plane::b() const
{
    return this->vec.y;
}

//------------------------------------------------------------------------------
/**
*/
inline scalar&
plane::c()
{
    return this->vec.z;
}

//------------------------------------------------------------------------------
/**
*/
inline scalar
plane::c() const
{
    return this->vec.z;
}

//------------------------------------------------------------------------------
/**
*/
inline scalar&
plane::d()
{
    return this->vec.w;
}

//------------------------------------------------------------------------------
/**
*/
inline scalar
plane::d() const
{
	return this->vec.w;
}

//------------------------------------------------------------------------------
/**
*/
inline scalar
plane::dot(const float4& v) const
{
	return float4::dot4(float4(vec),v);
    //return float4::unpack_x(XMPlaneDot(this->vec, v.vec));
}

//------------------------------------------------------------------------------
/** TODO: this function does not verified by now
 ** Warning: this function is assumed that the plane w is 0.0f,it passed ogrin point
*/
inline bool
plane::intersectline(const float4& startPoint, const float4& endPoint, float4& outIntersectPoint) const
{
	Ogre::Vector4 d = Ogre::Vector4(endPoint.vec.x,endPoint.vec.y,endPoint.vec.z,1.0) - Ogre::Vector4(startPoint.vec.x,startPoint.vec.y,startPoint.vec.z,1.0);
	float denom = vec.dotProduct(d);
	if (fabsf(denom) < std::numeric_limits<scalar>::epsilon())
	{
		//Parallel
		return false;
	}
	else
	{
		scalar nom = vec.dotProduct(Ogre::Vector4(startPoint.vec.x,startPoint.vec.y,startPoint.vec.z,0.0)) + vec.w;
		scalar t = -(nom/denom);
		if (t >= 0 && t <= 1)
		{
			Ogre::Vector3 intersectp = Ogre::Vector3(startPoint.x(),startPoint.y(),startPoint.z()) + t * Ogre::Vector3(d.x,d.y,d.z);
			outIntersectPoint.set_x(intersectp.x);
			outIntersectPoint.set_y(intersectp.y);
			outIntersectPoint.set_z(intersectp.z);
			outIntersectPoint.set_w(1.0f);
			return true; 
		}
		else
			return false;
		
	}
	/*
    outIntersectPoint = XMPlaneIntersectLine(this->vec, startPoint.vec, endPoint.vec);
    if (XMPlaneIsNaN(outIntersectPoint.vec))
    {
        return false;
    }
    else
    {
        return true;
    }
    */
}

//------------------------------------------------------------------------------
/**
*/
inline plane
plane::normalize(const plane& p)
{
	plane ret;
	ret.vec = float4::normalize(float4(p.vec)).vec;
	return ret;
	//return float4::normalize(float4(p.vec));
}
//------------------------------------------------------------------------------
/**
*/
inline void 
plane::set_a(scalar a)
{
    this->vec.x = a;
}

//------------------------------------------------------------------------------
/**
*/
inline void 
plane::set_b(scalar b)
{
	this->vec.y = b;
    //this->vec = XMVectorSetYPtr(this->vec, &b);
}

//------------------------------------------------------------------------------
/**
*/
inline void 
plane::set_c(scalar c)
{
	this->vec.z = c;
    //this->vec = XMVectorSetZPtr(this->vec, &c);
}

//------------------------------------------------------------------------------
/**
*/
inline void 
plane::set_d(scalar d)
{
	this->vec.w = d;
    //this->vec = XMVectorSetWPtr(this->vec, &d);
}

//------------------------------------------------------------------------------
/**
*/
inline ClipStatus::Type
plane::clip(const line& l, line& clippedLine) const
{
    n_assert(&l != &clippedLine);
    float d0 = this->dot(l.start());
    float d1 = this->dot(l.end());
    if ((d0 >= N_TINY) && (d1 >= N_TINY))
    {
        // start and end point above plane
        clippedLine = l;
        return ClipStatus::Inside;
    }
    else if ((d0 < N_TINY) && (d1 < N_TINY))
    {
        // start and end point below plane
        return ClipStatus::Outside;
    }
    else
    {
        // line is clipped
        point clipPoint;
        this->intersectline(l.start(), l.end(), clipPoint);
        if (d0 >= N_TINY)
        {
            clippedLine.set(l.start(), clipPoint);
        }
        else
        {
            clippedLine.set(clipPoint, l.end());
        }
        return ClipStatus::Clipped;
    }
}

//------------------------------------------------------------------------------
/**
*/
inline float
plane::distance(const point& po) const
{
	return a() * po.x() + b() * po.y() + c() * po.z() + d();
}

} // namespace Math
//------------------------------------------------------------------------------