CGAL users discussion list

[Steven <>]

Using CGAL 4.5.2. Below sample causes a bunch of precondition violations,
followed by an access violation exception. The funny thing is that if you
remove any of the 6 polygons from the input, everything runs fine. Why is
this happening? 

The only unusual thing about the polygons that I can see is that poly6 has a
duplicate point - but it is not self-intersecting, only touching, so I
believe this shouldn't be a problem? And as said above, when you remove any
of the other polygons, this polygon can be handled just fine. 

Is there a bug somewhere? Or is something wrong with my input? 

------------ 

typedef CGAL::Exact_predicates_exact_constructions_kernel Knl; 
typedef CGAL::Polygon_with_holes_2<Knl> Polygon_with_holes; 
typedef CGAL::Polygon_2<Knl> Polygon; 

int main(int argc, char* argv[]) 
{ 
        std::list<Polygon> polys; 

        Polygon poly1; 
        poly1.push_back(Point_2(417340.5, 523797.5)); 
        poly1.push_back(Point_2(419348.3269736591, 508552.92065337556)); 
        poly1.push_back(Point_2(421866.5, 489433.5)); 
        poly1.push_back(Point_2(421865.5, 489447.5)); 
        poly1.push_back(Point_2(417342.43500051671, 523783.40213909268)); 
        poly1.push_back(Point_2(417341.5, 523790.5)); 
        polys.push_back(poly1); 

        Polygon poly2; 
        poly2.push_back(Point_2(417342.43500051671, 523783.40213909268)); 
        poly2.push_back(Point_2(421865.5, 489447.5)); 
        poly2.push_back(Point_2(421837.5, 489724.5)); 
        poly2.push_back(Point_2(417365.15018218826, 523612.759577192)); 
        poly2.push_back(Point_2(417347.5, 523746.5)); 
        poly2.push_back(Point_2(417346.5, 523753.5)); 
        poly2.push_back(Point_2(417344, 523772)); 
        poly2.push_back(Point_2(417342.74397163116, 523781.15106382978)); 
        polys.push_back(poly2); 

        Polygon poly3; 
        poly3.push_back(Point_2(421837.5, 489724.5)); 
        poly3.push_back(Point_2(421832.5, 489771.5)); 
        poly3.push_back(Point_2(421831.5, 489780.5)); 
        poly3.push_back(Point_2(417365.84675276978, 523607.52457525046)); 
        polys.push_back(poly3); 

        Polygon poly4; 
        poly4.push_back(Point_2(421831.5, 489780.5)); 
        poly4.push_back(Point_2(421830.5, 489794.5)); 
        poly4.push_back(Point_2(417366.29927861993, 523604.12366546877)); 
        polys.push_back(poly4); 

        Polygon poly5; 
        poly5.push_back(Point_2(417322.5, 523931.5)); 
        poly5.push_back(Point_2(417318.5, 523966.5)); 
        poly5.push_back(Point_2(417317.5, 523968.5)); 
        polys.push_back(poly5); 

        Polygon poly6; 
        poly6.push_back(Point_2(417344, 523772)); 
        poly6.push_back(Point_2(417346.5, 523753.5)); 
        poly6.push_back(Point_2(417346.72222222225, 523752.16666666663)); 
        poly6.push_back(Point_2(417347.5, 523746.5)); 
        poly6.push_back(Point_2(417366.29927861993, 523604.12366546877)); 
        poly6.push_back(Point_2(421830.5, 489794.5)); 
        poly6.push_back(Point_2(421802.5, 490071.5)); 
        poly6.push_back(Point_2(417411.35391183395, 523265.52037297864)); 
        poly6.push_back(Point_2(417359.5, 523657.5)); 
        poly6.push_back(Point_2(417358.5, 523664.5)); 
        poly6.push_back(Point_2(417355.28571428568, 523688.92857142852)); 
        poly6.push_back(Point_2(417353.5, 523702.5)); 
        poly6.push_back(Point_2(417352.5, 523709.5)); 
        poly6.push_back(Point_2(417347.5, 523746.5)); 
        poly6.push_back(Point_2(417347.5, 523747.5)); 
        poly6.push_back(Point_2(417346.72222222225, 523752.16666666663)); 
        poly6.push_back(Point_2(417346.33333333337, 523755)); 
        polys.push_back(poly6); 

        list<Polygon_with_holes> polyHoles; 
        CGAL::join(polys.begin(), polys.end(),
std::back_inserter(polyHoles)); 
}



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