TL2LPline.h

#ifndef _mgTL2LPline_HH_
#define _mgTL2LPline_HH_

#include "Tl2/TL2Polyline.h"

/****************************************************************/
/*   Copyright (c) 2011 by DG Technologies, Inc.                */
/*                       All rights reserved.                   */
/****************************************************************/

class MGPosition;


class mgTL2LPline{

public:

mgTL2LPline():m_polyline(0),m_idS(0),m_nV(0){;};

mgTL2LPline(
    const mgTL2LPline& lpline
):m_polyline(lpline.m_polyline),m_idS(lpline.m_idS),m_nV(lpline.m_nV){;};

//Constructor of whole mgTL2Polyline.
mgTL2LPline(
    const mgTL2Polyline* polyline   //Original mgTL2Polyline pointer.
):m_polyline(polyline),m_idS(0),m_nV(polyline->bdim()){;};

mgTL2LPline(
    const mgTL2Polyline* polyline,  //Original mgTL2Polyline pointer.
    int idS, //starting id. Not relative, but absolute value of m_polyline.
    int nV
):m_polyline(polyline),m_idS(idS),m_nV(nV){;};

mgTL2LPline(
    const mgTL2LPline& lpline,
    int idS, //starting id of lpline
    int nV
);


//Change m_polyline's id to this mgTL2LPline's id.
//Function's return value is true if id_in is valid id for this mgTL2LPline.
//False if not.
bool change_id(
    int id_in,  //id of m_polyline.
    int& id_out //id of this will be output.
)const;

mgTL2LPline* clone()const;

//Evaluation of this with the normalized parameter value t from 0. to 1.
//is provided. t=0. for the start point, t=1. for the end point.
MGVector eval(double t, int nderi=0)const;

//Get id of m_Bpolylines of m_param of m_polyline from vertex id i.
//Function's return value is
//true if the point of t is a boundary point, false if not.
bool get_id_from_VertexID(int i, short id[3])const;

bool is_null()const{return m_polyline==0;};
void setNull();

//Compute the intersections of sl and this mgTL2LPline.
//Function's return value is the (nearest) intersection vertex id of lp if >=0.
//If return value is minus, intersection not found.
int isectSlTl(
    const MGStraight& sl
)const;

//Update this by limiting the parameter range of the curve.
mgTL2LPline& limit(
    int idS,    //start point id of this mgTL2LPline.
    int nV  //Number of vertices.
);

//Get the number of points of this polyline.
int number_of_points()const;

std::auto_ptr<mgTL2Polyline> getPolygonizedMidLine(
    const mgTL2LPline& lp2,
    int& id0, int& id2
)const;

//Polygonize of the (u,v) space straight line from this->uv(id1V) to pline2.uv(id2V).
//The direction of the output is from id1V to id2V.
//polygonizeSL does ensure the deviation from the surface to be within the surface
//tolerance.
std::auto_ptr<mgTL2Polyline> polygonizeSL(
    const mgTL2LPline& pline2,
    int id1V,   //id of this vertex.
    int id2V    //id of pline2's vertex.
)const;

std::ostream& out(std::ostream& ostrm)const;

//Reverse the direction.
void reverse();

//Subdivide at the id.
void subdivide(
    int id, //Relative one that start from 0 even for opposite direction.
    mgTL2LPline& lp1,   //devided 1st mgTL2LPline.
    mgTL2LPline& lp2    //devided 2nd mgTL2LPline.
)const;

//Obtain the mid point of this line.
void mid(MGPosition& uvmid);

const mgTL2Polyline* TL2Polyline()const{return m_polyline;};
const mgTL2parameter& TL2param()const{return m_polyline->TL2param();};

//Get i-th point surface parameter (u,v) of this polyline
MGPosition uv(int i)const;

//Get i-th point(x,y,z) of this polyline
MGPosition xyz(int i, bool need_normal=false)const;

friend std::ostream& operator<< (std::ostream& ot, const mgTL2LPline& poly){
    return poly.out(ot);};

private:
    const mgTL2Polyline* m_polyline;//Original mgTL2Polyline pointer.
    int m_idS;//starting id. Not relative, but absolute value of m_polyline.
    int m_nV;   //Number of vertices.
                //When m_nv>0, this mgTL2LPline's direction is the same as m_polyline's.
                //When m_nv<0, this mgTL2LPline's direction is opposite to m_polyline's.
        
};
 // end of UseTessellation group
#endif