CGAL users discussion list

[Bernhard Kornberger <>]

 schrieb:
> I had a quicklook at your files and they are not easy to read...
> could you better isolate the problem?
> In your first test, it seems that the program crashes only AFTER the 
> triangulation is built ("Starting Postprocessing..."), right?
>
> best
>     Monique

Thank you for the answer. I had a closer look at the problem and it
seems that what I have reported are actually two different problems.

The first problem:
==================

The first problem is the crash when no debugger is used. It is not
related to Regular_Triangulation_3 but to the convex hull. I was able
to generate a really small example where something bad happens:

CopyPaste:
###########################################################
bkorn@pepper:~/spheres_dev/test
 $ cat minkowski.cpp
#include <iostream>

#include <CGAL/Exact_predicates_exact_constructions_kernel.h>
#include <CGAL/Filtered_kernel.h>

#include <CGAL/Convex_hull_d.h>
#include <CGAL/Convex_hull_d_traits_3.h>
#include <CGAL/Convex_hull_d_to_polyhedron_3.h>

using namespace std;

typedef CGAL::Exact_predicates_exact_constructions_kernel K;

// Convex hull
typedef CGAL::Convex_hull_d_traits_3<K>        Hull_traits_3;
typedef CGAL::Convex_hull_d< Hull_traits_3 >   Convex_hull_3;
typedef CGAL::Polyhedron_3<K> Polyhedron;
typedef Polyhedron::Facet_iterator PFacet_iterator;
typedef K::Point_3 Point;
int main(int argc, char *argv[])
{
        Convex_hull_3 cHull(3);
        cHull.insert(Point(0,0,0));
        cHull.insert(Point(0,0,1));
        cHull.insert(Point(0,1,0));
        cHull.insert(Point(1,0,0));
        Polyhedron poly;
        CGAL::convex_hull_d_to_polyhedron_3(cHull,poly);

        cout << "Now we show the cHull's planes"<<endl;
        for(PFacet_iterator 
f_it=poly.facets_begin();f_it!=poly.facets_end();++f_it)
        {
                cout << "facet_degree="<<f_it->facet_degree()<<endl;
                cout << "plane="<<f_it->plane()<<endl;
        }
}
###########################################################


This is the program's output:

CopyPaste:
###########################################################
bkorn@pepper:~/spheres_dev/test
 $ ./minkowski
Now we show the cHull's planes
facet_degree=3
plane=0 0 0 0
facet_degree=3
plane=0 0 0 0
facet_degree=3
plane=0 0 0 0
facet_degree=3
plane=0 0 0 0
###########################################################

Probably I've used the convex hull in a wrong way and the error is
that I should have inserted Point_d points, right? But then I would
expect an error from the compiler or at least an assertion instead
of invalid planes that lead to errors somewhere else.



The second problem:
===================

The second problem occurs only when the software runs in the valgrind
debugger. It is indeed related to Regular_Triangulation_3. I have
simplified the code I gave you last time:


The main routine calls the Triangulator's constructor:

CopyPaste:
###########################################################
int main(int argc, char *argv[])
{
   Triangulator* powerDiagram=new Triangulator();
   return 0;
}
###########################################################

This is the constructor:

CopyPaste:
###########################################################
Triangulator::Triangulator()
{
   cout << "Triangulator: inserting 8 bounding spheres"<<endl;
   double l=-2396.4;
   double u=2595.59;
 vBoundingVertices.insert(regTr.insert(Weighted_point(Point(l,l,l,1))));
   cout << "a"<<endl;
   vBoundingVertices.insert(regTr.insert(Weighted_point(Point(l,l,u,1))));
   cout << "b"<<endl;
   vBoundingVertices.insert(regTr.insert(Weighted_point(Point(l,u,l,1))));
   cout << "c"<<endl;
   vBoundingVertices.insert(regTr.insert(Weighted_point(Point(l,u,u,1))));
   cout << "d"<<endl;
   vBoundingVertices.insert(regTr.insert(Weighted_point(Point(u,l,l,1))));
   cout << "e"<<endl;
   vBoundingVertices.insert(regTr.insert(Weighted_point(Point(u,l,u,1))));
   cout << "f"<<endl;
   vBoundingVertices.insert(regTr.insert(Weighted_point(Point(u,u,l,1))));
   cout << "g"<<endl;
   vBoundingVertices.insert(regTr.insert(Weighted_point(Point(u,u,u,1))));
   cout << "h"<<endl;
}
###########################################################


Here is the output if NO debugger is used:

CopyPaste:
###########################################################
./minkowski

/usr/bin/g++   -o minkowski minkowski.o Triangulator.o UnionOfSpheres.o 
VisualizerGV.o  -lm -ldl -pg  '-L/opt/CGAL330/lib' -L/usr/lib/qt3 
-Wl,-R/opt/CGAL330/lib/i686_Linux-2.6_g++-4.1.2:/usr/lib/qt3 -lCGAL 
-lCGALcore++ -lCGALQt -lCGALimageIO -lCGALPDB -lqt-mt -lGL -lGLU -lz 
-lmpfr -lgmpxx -lgmp -lX11 -lboost_program_options -lm
Triangulator: inserting 8 bounding spheres
a
b
c
d
e
f
g
h
###########################################################

..everything is okay. But if a debugger is used:

CopyPaste:
###########################################################
valgrind ./minkowski

/usr/bin/g++   -o minkowski minkowski.o Triangulator.o UnionOfSpheres.o 
VisualizerGV.o  -lm -ldl -pg  '-L/opt/CGAL330/lib' -L/usr/lib/qt3 
-Wl,-R/opt/CGAL330/lib/i686_Linux-2.6_g++-4.1.2:/usr/lib/qt3 -lCGAL 
-lCGALcore++ -lCGALQt -lCGALimageIO -lCGALPDB -lqt-mt -lGL -lGLU -lz 
-lmpfr -lgmpxx -lgmp -lX11 -lboost_program_options -lm
==9568== Memcheck, a memory error detector.
==9568== Copyright (C) 2002-2006, and GNU GPL'd, by Julian Seward et al.
==9568== Using LibVEX rev 1658, a library for dynamic binary translation.
==9568== Copyright (C) 2004-2006, and GNU GPL'd, by OpenWorks LLP.
==9568== Using valgrind-3.2.1-Debian, a dynamic binary instrumentation 
framework.
==9568== Copyright (C) 2000-2006, and GNU GPL'd, by Julian Seward et al.
==9568== For more details, rerun with: -v
==9568==
Triangulator: inserting 8 bounding spheres
a
b
c
d
e
f
CGAL error: precondition violation!
Expr: orientation(p0, p1, p2, p3) == POSITIVE
File: /opt/CGAL330/include/CGAL/Regular_triangulation_3.h
Line: 890
terminate called after throwing an instance of 'std::logic_error'
  what():  basic_string::_S_construct NULL not valid
==9568==
==9568== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 97 from 1)
==9568== malloc/free: in use at exit: 1,125,702 bytes in 531 blocks.
==9568== malloc/free: 578 allocs, 47 frees, 1,128,077 bytes allocated.
==9568== For counts of detected errors, rerun with: -v
==9568== searching for pointers to 531 not-freed blocks.
==9568== checked 2,180,184 bytes.
==9568==
==9568== LEAK SUMMARY:
==9568==    definitely lost: 0 bytes in 0 blocks.
==9568==      possibly lost: 149 bytes in 4 blocks.
==9568==    still reachable: 1,125,553 bytes in 527 blocks.
==9568==         suppressed: 0 bytes in 0 blocks.
==9568== Reachable blocks (those to which a pointer was found) are not 
shown.
==9568== To see them, rerun with: --show-reachable=yes
Aborted (core dumped)

###########################################################

You can download this simplified example here:

http://dist.ist.tugraz.at/test2.tar.bz2

Best regards
Bernhard