//----------------------------------------------------------------------------
//  EgalTech 2013-2013
//----------------------------------------------------------------------------
// File : DistPointLine.cpp       Data : 17.12.13          Versione : 1.4l1
// Contenuto : Implementazione dell'oggetto distanza punto da linea/segmento.
//
// !!! ToDo : Gestire i sistemi di riferimento.
//
// Modifiche : 17.12.13 DS Creazione modulo.
//
//
//----------------------------------------------------------------------------

//--------------------------- Include ----------------------------------------
#include "stdafx.h"
#include "\EgtDev\Include\EGkDistPointLine.h"


//----------------------------------------------------------------------------
DistPointLine::DistPointLine( void)
{
   m_dLen = 0 ;
   m_bIsSegment = false ;
   m_dSqDist = - 1 ;
   m_dDist = - 1 ;
}

//----------------------------------------------------------------------------
bool
DistPointLine::Set( const Point3d& ptP, const Point3d& ptIni, const Point3d& ptFin, bool bIsSegment)
{
   m_ptP = ptP ;
   m_ptIni = ptIni ;
   m_dLen = Dist( ptIni, ptFin) ;
   if ( m_dLen > EPS_SMALL)
      m_vtDir = ( ptFin - ptIni) / m_dLen ;
   else
      m_vtDir.Set( 0, 0, 0) ;
   m_bIsSegment = bIsSegment ;
   m_dSqDist = - 1 ;
   m_dDist = - 1 ;

   return true ;
}

//----------------------------------------------------------------------------
bool
DistPointLine::SetPoint( const Point3d& ptP)
{
   m_ptP = ptP ;
   m_dSqDist = - 1 ;
   m_dDist = - 1 ;

   return true ;
}

//----------------------------------------------------------------------------
bool
DistPointLine::SetLine( const Point3d& ptIni, const Point3d& ptFin, bool bIsSegment)
{
   m_ptIni = ptIni ;
   m_dLen = Dist( ptIni, ptFin) ;
   if ( m_dLen > EPS_SMALL)
      m_vtDir = ( ptFin - ptIni) / m_dLen ;
   else
      m_vtDir.Set( 0, 0, 0) ;
   m_bIsSegment = bIsSegment ;
   m_dSqDist = - 1 ;
   m_dDist = - 1 ;

   return true ;
}

//----------------------------------------------------------------------------
bool
DistPointLine::Calculate( void)
{
  // se la linea è un punto
   if ( m_dLen < EPS_SMALL)
      m_ptMinDist = m_ptIni ;

  // se la linea è illimitata
   else if ( ! m_bIsSegment)
      m_ptMinDist = m_ptIni + m_vtDir * ( m_vtDir * ( m_ptP - m_ptIni)) ;

  // altrimenti la linea è un segmento
   else {
      double dProiez = m_vtDir * ( m_ptP - m_ptIni) ;
      if ( dProiez <= 0)
         m_ptMinDist = m_ptIni ;
      else if ( dProiez >= m_dLen)
         m_ptMinDist = m_ptIni + m_vtDir * m_dLen ;
      else
         m_ptMinDist = m_ptIni + m_vtDir * dProiez ;
   }

  // calcolo il quadrato della distanza
   m_dSqDist = SqDist( m_ptP, m_ptMinDist) ;

   return true ;
}

//----------------------------------------------------------------------------
double
DistPointLine::GetSqDist( void)
{
  // se necessario, faccio eseguire i conti
   if ( m_dSqDist < 0)
      Calculate() ;

   return m_dSqDist ;
}

//----------------------------------------------------------------------------
double
DistPointLine::GetDist( void)
{
  // se necessario, faccio eseguire i conti
   if ( m_dSqDist < 0)
      Calculate() ;
   if ( m_dDist < 0)
      m_dDist = sqrt( m_dSqDist) ;

   return m_dDist ;
}

//----------------------------------------------------------------------------
const Point3d&
DistPointLine::GetPointMinDist( void)
{
  // se necessario, faccio eseguire i conti
   if ( m_dSqDist < 0)
      Calculate() ;

   return m_ptMinDist ;
}