source: trunk/src/PixelMap/Scan.cc

// -----------------------------------------------------------------------
// Scan.cc: Member functions for the Scan class.
// -----------------------------------------------------------------------
// Copyright (C) 2006, Matthew Whiting, ATNF
//
// This program is free software; you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2 of the License, or (at your
// option) any later version.
//
// Duchamp is distributed in the hope that it will be useful, but WITHOUT
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
// for more details.
//
// You should have received a copy of the GNU General Public License
// along with Duchamp; if not, write to the Free Software Foundation,
// Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA
//
// Correspondence concerning Duchamp may be directed to:
//    Internet email: Matthew.Whiting [at] atnf.csiro.au
//    Postal address: Dr. Matthew Whiting
//                    Australia Telescope National Facility, CSIRO
//                    PO Box 76
//                    Epping NSW 1710
//                    AUSTRALIA
// -----------------------------------------------------------------------
#include <duchamp/PixelMap/Scan.hh>
#include <iostream>
#include <math.h>
#include <stdlib.h>

namespace PixelInfo
{

  Scan::Scan()
  {
    this->itsY=-1;
    this->itsX=-1;
    this->itsXLen=0;
  }

  Scan::Scan(long y, long x, long xl):
    itsY(y), itsX(x),itsXLen(xl)
  {
  }

  Scan::Scan(const Scan& s)
  {
    operator=(s);
  }
  //------------------------------------------------------
  
  Scan& Scan::operator= (const Scan& s)
  {    
    if(this == &s) return *this;
    this->itsY=s.itsY; 
    this->itsX=s.itsX; 
    this->itsXLen=s.itsXLen;
    return *this;
  }
  //------------------------------------------------------

  bool Scan::addScan(const Scan &other)
  {
    bool altered=this->touches(other);
    if(altered){
      long x = std::min(this->itsX,other.itsX);
      long xmax = std::max(this->itsX+this->itsXLen-1,other.itsX+other.itsXLen-1);
      this->itsX=x;
      this->itsXLen=xmax-x+1;
    }
    return altered;
  }


  Scan nullScan()
  {
    /// A simple way of returning a scan with zero length.
    Scan null(-1,-1,0); 
    return null;
  }

  bool Scan::isNull()
  {
    return (itsY==-1 && itsX==-1 && itsXLen==0);
  }

  //------------------------------------------------------

  Scan unite(Scan &scan1, Scan &scan2)
  {
    /// Return a scan that includes all pixels from both scans, but
    /// only if they overlap. If they do not, return the null scan.

    Scan joined;
    if(!touching(scan1,scan2)){
      joined = nullScan();
    }
    else{
      long y = scan1.getY();
      long x = std::min(scan1.getX(),scan2.getX());
      long xmax = std::max(scan1.getXmax(),scan2.getXmax());
      joined.define(y,x,xmax-x+1);
    }
    return joined;
  }

  //------------------------------------------------------

  Scan intersect(Scan &scan1, Scan &scan2)
  {
    /// Return a scan that includes all pixels that lie in both scans.
    /// 
    /// If they do not overlap, return the null scan.

    Scan intersection;
    if(!scan1.overlaps(scan2)){
      intersection = nullScan();
    }
    else{
      long y = scan1.getY();
      long x = std::max(scan1.getX(),scan2.getX());
      long xmax = std::min(scan1.getXmax(),scan2.getXmax());
      intersection.define(y,x,xmax-x+1);
    }
    return intersection;
  }
  //------------------------------------------------------

  bool Scan::touches(const Scan &other)
  {
    return this->overlaps(other) || this->isAdjacentTo(other);
  }

  bool Scan::overlaps(const Scan &other)
  {
    if(this->itsY != other.itsY) return false;
    else if(this->itsX <= other.itsX){
      return (other.itsX < (this->itsX+this->itsXLen));
    }
    else{
      return (this->itsX < (other.itsX+other.itsXLen));
    }
  }

  bool Scan::isAdjacentTo(const Scan &other)
  {
    if(this->itsY != other.itsY) return false;
    else if(this->itsX <= other.itsX){
      return (other.itsX == (this->itsX+this->itsXLen));
    }
    else{
      return (this->itsX == (other.itsX+other.itsXLen));
    }
  }
  //------------------------------------------------------

  bool touching(Scan &scan1, Scan &scan2)
  {
    ///  Test whether two scans either overlap, or lie adjacent
    ///  (ie. there are no pixels lying between the two scans).
    /// \return A bool value.

    return overlap(scan1,scan2) || adjacent(scan1,scan2);
  
  }
  //------------------------------------------------------

  bool overlap(Scan &scan1, Scan &scan2)
  {
    ///  Test whether two scans overlap, ie. they have pixels in
    ///  common.
    /// \return A bool value.

    if(scan1.getY()!=scan2.getY()) return false;
    else if(scan1.getX() <= scan2.getX())
      return (scan2.getX() <= scan1.getXmax());
    else
      return (scan1.getX() <= scan2.getXmax());
  
  }
  //------------------------------------------------------

  bool adjacent(Scan &scan1, Scan &scan2)
  {
     /// Test whether two scans lie adjacent (ie. there are no pixels
     /// lying between the two scans).  If they overlap, return false.
     /// \return A bool value.

    if(scan1.getY()!=scan2.getY()) return false;
    else if(scan1.getX() <= scan2.getX())
      return (scan2.getX() == scan1.getXmax()+1);
    else
      return (scan1.getX() == scan2.getXmax()+1);
  
  }
  //------------------------------------------------------

  std::ostream& operator<< ( std::ostream& theStream, Scan& scan)
  {
    ///  Output the three key parameters of the scan.

    if(scan.isNull()) theStream << "NULL";
    else{
      theStream << scan.itsX;
      theStream << "-" << scan.getXmax();
      theStream << ", " << scan.itsY;
    }
    return theStream;
  }
  //------------------------------------------------------

  bool operator< (Scan lhs, Scan rhs)
  {
    /// Test for less-than first on the y-values, and if they are
    /// equal, test on the starting x-value, and then finally on the
    /// length.
    /// 
    /// This is necessary for sorting functions on lists of Scans (used
    /// by the Object2D class).

    if(lhs.itsY != rhs.itsY)      return (lhs.itsY    < rhs.itsY);
    else if(lhs.itsX != rhs.itsX) return (lhs.itsX    < rhs.itsX);
    else                          return (lhs.itsXLen < rhs.itsXLen);
  }
  //------------------------------------------------------

  bool operator== (Scan lhs, Scan rhs)
  {
    /// For two scans to be equal, all three parameters must be equal.

    return (lhs.itsY == rhs.itsY) &&
      (lhs.itsX == rhs.itsX) &&
      (lhs.itsXLen == rhs.itsXLen);
  }
  //------------------------------------------------------

  bool Scan::isInScan(long x, long y)
  {
    return (y == this->itsY) &&
      ( (x>= this->itsX) && (x < (this->itsXLen+this->itsX)) );
  }
  //------------------------------------------------------

  float minSep(Scan &s1, Scan &s2)
  {
 
    if(s1.getX() > s2.getXmax()) return hypot(s1.getX()-s2.getXmax(),s1.getY()-s2.getY());
    else if(s2.getX() > s1.getXmax()) return hypot(s2.getX()-s1.getXmax(),s1.getY()-s2.getY());
    else return abs(s1.getY()-s2.getY());
   
  }
  //------------------------------------------------------
  
  
  void mergeList(std::vector<Scan> scanlist)
  {
    std::vector<Scan>::iterator iter;
    unsigned int counter=0,compCounter;
    while(counter<(scanlist.size()-1)){

      
      compCounter = counter+1;
      
      do{
        
        if(touching(scanlist[counter],scanlist[compCounter])){
          Scan temp = unite(scanlist[counter],scanlist[compCounter]);
          iter = scanlist.begin()+compCounter;
          scanlist.erase(iter);
          iter = scanlist.begin()+counter;
          scanlist.erase(iter);
          scanlist.push_back(temp);
        }
        else compCounter ++;
      }while(compCounter < scanlist.size());

      counter++;
    }

  }


}