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Re: [cgal-discuss] Error with intersection in boolean set operations


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  • From: Pedro Machado Manhães de Castro <>
  • To:
  • Subject: Re: [cgal-discuss] Error with intersection in boolean set operations
  • Date: Mon, 22 Jun 2009 12:37:20 +0200
  • Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=TLESVCubxkyrvS8v4F/atLWk+C9U5rQHsK6aQL/KhyMN+GfKicEwR49/uVvg9nfqOA jbA1p4G52WTXqeoBOVhAOmaxTz0TqayAFV0n0yVuWpZ7L4pPmKjeg+ahUebtpAvg1/ew vKCPA8BSPKK5zrFTmxCULvFKszVCIokc6XSes=
I think you are probably choosing the wrong number type.
Read http://www.cgal.org/FAQ.html#inexact_NT .
CGAL::Simple_cartesian<double> // Inexact Number Type

Cheers,
Pedro Machado Manhaes de Castro

On Mon, Jun 22, 2009 at 10:54 AM, Francisco Miguel Romero Medina <> wrote:
Hi All, 
I have the following error in the intersection  boolean set operation:
 
CGAL error: precondition violation!
Expr: cv1.point_position (p) == EQUAL && cv2.point_position (p) == EQUAL
File: C:\Archivos de programa\CGAL-3.3.1\include\CGAL/Arr_circle_segment_traits_
2.h
Line: 247
I have used a test program than compute a simple intersection as show in the figure
 
 
with this the program code:
 

#include "bso_rational_nt.h"

#include <CGAL/Simple_cartesian.h>

#include <CGAL/Gps_circle_segment_traits_2.h>

#include <CGAL/General_polygon_set_2.h>

#include <CGAL/General_polygon_with_holes_2.h>

#include <CGAL/Lazy_exact_nt.h>

#include <CGAL/squared_distance_2.h>

#include <CGAL/Object.h>

#include <CGAL/intersections.h>

#include <CGAL/Boolean_set_operations_2.h> 

#include <CGAL/enum.h>

 

enum Sign { NEGATIVE, ZERO, POSITIVE};

typedef Sign  Orientation;

 

typedef CGAL::Simple_cartesian<double>                  Kernel;

typedef Kernel::Point_2                                 Point_2;

typedef Kernel::Circle_2                                Circle_2;

typedef Kernel::Line_2                                    Line_2;

typedef Kernel::Segment_2                          Segment_2;

typedef CGAL::Gps_circle_segment_traits_2<Kernel>       Traits_2;

 

typedef CGAL::General_polygon_set_2<Traits_2>           Polygon_set_2;

typedef Traits_2::Polygon_with_holes_2                  Polygon_with_holes_2;

typedef Traits_2::Curve_2                               Curve_2;

typedef Traits_2::X_monotone_curve_2                    X_monotone_curve_2;

typedef Traits_2::Point_2                                                 TPoint_2;

typedef Polygon_with_holes_2::General_polygon_2         Polygon_2;

 

 

int main (int argc, char * argv[])

{

 

  std::list<Polygon_2> polygons;

 

  Polygon_2 pgn;

  X_monotone_curve_2 s1(Point_2(449.268,624.272),Point_2(128.151,1180.46));         

  pgn.push_back(s1);

  X_monotone_curve_2 s2(Point_2(128.151,1180.46),Point_2(-514.084,1180.46));  

  pgn.push_back(s2);

  X_monotone_curve_2 s3(Point_2(-514.084,1180.46),Point_2(-835.202,624.272));

  pgn.push_back(s3);

  X_monotone_curve_2 s4(Point_2(-835.202,624.272),Point_2(-514.084,68.0801));   

  pgn.push_back(s4);

  X_monotone_curve_2 s5(Point_2(-514.084,68.0801),Point_2(128.151,68.0801));     

  pgn.push_back(s5);

  X_monotone_curve_2 s6(Point_2(128.151,68.0801),Point_2(449.268,624.272));

  pgn.push_back(s6);

 

  polygons.push_back (pgn);

 

 

  Polygon_2 pgn2;

  X_monotone_curve_2 r1(Point_2(101,2),Point_2(1,102));     

  pgn2.push_back(r1);

  X_monotone_curve_2 r2(Point_2(1,102),Point_2(-99,2));   

  pgn2.push_back(r2);

  X_monotone_curve_2 r3(Point_2(-99,2),Point_2(1,-98));   

  pgn2.push_back(r3);

  X_monotone_curve_2 r4(Point_2(1,-98),Point_2(101,2));   

  pgn2.push_back(r4);

 

  polygons.push_back (pgn2);

 

 

  std::list<Polygon_with_holes_2> res;

 

  // HERE IS THE ERROR

  CGAL::intersection (polygons.begin(), polygons.end(), std::back_inserter (res));

 

 

    std::copy (res.begin(), res.end(),

             std::ostream_iterator<Polygon_with_holes_2>(std::cout, "\n"));

  std::cout << std::endl;

  system("pause");

  return 0;

}

 
 
Otherwise I really want compute the intersection of polygons that support both circle and line segments. An test example is the next:
 
 
with this the program code:
 

#include "bso_rational_nt.h"

#include <CGAL/Simple_cartesian.h>

#include <CGAL/Gps_circle_segment_traits_2.h>

#include <CGAL/General_polygon_set_2.h>

#include <CGAL/General_polygon_with_holes_2.h>

#include <CGAL/Lazy_exact_nt.h>

#include <CGAL/squared_distance_2.h>

#include <CGAL/Object.h>

#include <CGAL/intersections.h>

#include <CGAL/Boolean_set_operations_2.h> 

#include <CGAL/enum.h>

 

enum Sign { NEGATIVE, ZERO, POSITIVE};

typedef Sign  Orientation;

 

typedef CGAL::Simple_cartesian<double>                  Kernel;

typedef Kernel::Point_2                                 Point_2;

typedef Kernel::Circle_2                                Circle_2;

typedef Kernel::Line_2                                    Line_2;

typedef Kernel::Segment_2                          Segment_2;

typedef CGAL::Gps_circle_segment_traits_2<Kernel>       Traits_2;

 

typedef CGAL::General_polygon_set_2<Traits_2>           Polygon_set_2;

typedef Traits_2::Polygon_with_holes_2                  Polygon_with_holes_2;

typedef Traits_2::Curve_2                               Curve_2;

typedef Traits_2::X_monotone_curve_2                    X_monotone_curve_2;

typedef Traits_2::Point_2                                                 TPoint_2;

typedef Polygon_with_holes_2::General_polygon_2         Polygon_2;

 

 

Polygon_2 construct_polygon (const Circle_2& circle)

{

  // Subdivide the circle into two x-monotone arcs.

  Traits_2 traits;

  Curve_2 curve (circle);

  std::list<CGAL::Object> objects;

  traits.make_x_monotone_2_object() (curve, std::back_inserter(objects));

  CGAL_assertion (objects.size() == 2);

 

  // Construct the polygon.

  Polygon_2 pgn;

  X_monotone_curve_2 arc;

  std::list<CGAL::Object>::iterator iter;

 

  for (iter = objects.begin(); iter != objects.end(); ++iter) {

    CGAL::assign (arc, *iter);

    pgn.push_back (arc);

  }

 

  return pgn;

}

 

 

int main (int argc, char * argv[])

{

 

  std::list<Polygon_2> circles;

 

  

  Polygon_2 pgn;

  X_monotone_curve_2 s1(Point_2(88,49),Point_2(53,87));   

  pgn.push_back(s1);

  X_monotone_curve_2 s2(Point_2(53,87),Point_2(3,101));   

  pgn.push_back(s2);

  X_monotone_curve_2 s3(Point_2(3,101),Point_2(-46,89));   

  pgn.push_back(s3);

  X_monotone_curve_2 s4(Point_2(-46,89),Point_2(-84,54));  

  pgn.push_back(s4);

  X_monotone_curve_2 s5(Point_2(-84,54),Point_2(-98,4)); 

  pgn.push_back(s5);

  X_monotone_curve_2 s6(Point_2(-98,4),Point_2(-86,-45)); 

  pgn.push_back(s6);

  X_monotone_curve_2 s7(Point_2(-86,-45),Point_2(-51,-83)); 

  pgn.push_back(s7);

  X_monotone_curve_2 s8(Point_2(-51,-83),Point_2(-1,-97)); 

  pgn.push_back(s8);

  X_monotone_curve_2 s9(Point_2(-1,-97),Point_2(48,-85)); 

  pgn.push_back(s9);

  X_monotone_curve_2 s10(Point_2(48,-85),Point_2(86,-50));

  pgn.push_back(s10);

  X_monotone_curve_2 s11(Point_2(86,-50),Point_2(100,0)); 

  pgn.push_back(s11);

  X_monotone_curve_2 s12(Point_2(100,0),Point_2(88,49)); 

  pgn.push_back(s12);

 

  circles.push_back (pgn);

 

  circles.push_back (construct_polygon (Circle_2(Point_2(-192.967,624.272),  412465.795225)));

 

   std::list<Polygon_with_holes_2> res;

 

  // HERE IS THE ERROR

  CGAL::intersection (circles.begin(), circles.end(), std::back_inserter (res));

 

 

  std::copy (res.begin(), res.end(),

             std::ostream_iterator<Polygon_with_holes_2>(std::cout, "\n"));

  std::cout << std::endl;

  system("pause");

  return 0;

}

 
With the same error
 
 
Can anybody help me ?   I already don´t know where it is the problem.
 
Thanks
 
Francisco
 


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