position.cpp

basic mathematic classes used for math programming

#include "mathclass.h"

position
interpolate( m_real t, position const& a, position const& b )
{
    position c;

    c.p[0] = (1.0-t)*a.p[0] + t*b.p[0];
    c.p[1] = (1.0-t)*a.p[1] + t*b.p[1];
    c.p[2] = (1.0-t)*a.p[2] + t*b.p[2];

    return c;
}

m_real
distance( position const& p1, position const& p2 )
{
    return len(p2-p1);
}

m_real
distance( position const& p, position const& p1, position const& p2 )
{
    vector v1 = p2 - p1;
    vector v2 = p - p1;
    m_real t = ( v1 % v2 ) / ( v1 % v1 );
    position p3 = p1 + t*v1;

    return distance( p, p3 );
}

ostream& operator<<( ostream& os, position const& a )
{
    os << "( " << a.p[0] << " , " << a.p[1] << " , " << a.p[2] << " )";
    return os;
}

istream& operator>>( istream& is, position& a )
{
	static char buf[256];
	// is >> "(" >> a.p[0] >> "," >> a.p[1] >> "," >> a.p[2] >> ")";
    is >> buf >> a.p[0] >> buf >> a.p[1] >> buf >> a.p[2] >> buf;

    return is;
}