laLine3 Class Reference

3D line segment More...

#include <laLine3.h>

Public Member Functions
	laLine3 (laPoint3 &a, laPoint3 &b)
laPoint3	intersection (laLine3 &l, double &pk1)
	Find point of intersection (or nearest point) to another laLine3. More...
laPoint3	intersection (class laPlane3 &pn, double *pk=NULL)
	Find point of intersection with laPlane3.
void	draw (class laRenderer *r, laPoint3 pos)
	Draw the line ( primarily for debug purposes )
Line constructors and initialization methods
void	build_2pt (laPoint3 &a, laPoint3 &b)
	Build from two end-points.
void	build_vec (laPoint3 &a, laPoint3 &v)
	Build from an end-poind and vector.
Lenght of the segment
double	lenght () const
double	lenght_sq () const
	Squared root of segment lenght.
Getting points at different positions on the line
laPoint3	end () const
	Get endpoint.
void	at (double k, laPoint3 *ppt) const
	Get point at 1/k lenght (returns in user-specified pointer) More...
laPoint3	at (double k) const

Public Attributes
laPoint3	origin
	Point of origin.
laPoint3	vector
	Vector ( not normalized, so k = [0;1] traces the whole line segment )

Detailed Description

3D line segment

Author

Atanas Laskov

Definition at line 40 of file laLine3.h.

Member Function Documentation

void laLine3::at ( double  k, laPoint3 *  ppt  ) const

inline

Get point at 1/k lenght (returns in user-specified pointer)

Get point at 1/k lenght (retruns a new object)

Definition at line 85 of file laLine3.h.

Referenced by intersection().

laPoint3 laLine3::intersection	(	laLine3 &	l,
		double &	pk1
	)

Find point of intersection (or nearest point) to another laLine3.

= is not a good idea for double vars

Definition at line 48 of file laLine3.cpp.

{
    double k1;
    double btm;

    //yz
    btm = vector.z()*l.vector.y() - vector.y()*l.vector.z();
    if((btm)!=0){   
        k1 = -( vector.y()*origin.z() + vector.z()*l.origin.y() - vector.z()*origin.y() - vector.y()*l.origin.z() )/
              ( btm );
        pk1 = k1;

        laPoint3 pt; l.at(k1, &pt);
        return pt;
    }

    //xz
    btm = vector.z()*l.vector.x() - vector.x()*l.vector.z();
    if((btm)!=0){
        k1 = -( vector.x()*origin.z() + vector.z()*l.origin.x() - vector.z()*origin.x() - vector.x()*l.origin.z() )/
              ( btm );
        pk1 = k1;

        laPoint3 pt; l.at(k1, &pt);
        return pt;
    }

    //xy;
    btm = vector.y()*l.vector.x() - vector.x()*l.vector.y();
    if((btm)!=0){
        k1 = -( vector.x()*origin.y() + vector.y()*l.origin.x() - vector.y()*origin.x() - vector.x()*l.origin.y() )/
            ( btm );
        pk1 = k1;

        laPoint3 pt; l.at(k1, &pt);
        return pt;
    }

    k1 = 999;   //wtf??
    pk1 = k1;

    laPoint3 pt; l.at(k1, &pt);
    return pt;
}

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The documentation for this class was generated from the following files:

• Source/Core/laLine3.h
• Source/Core/laLine3.cpp