hello! i progressed with my dragon... i used the Naca sweep from parkingbot, with excellent results, until.... i tried to put 2 sweeped objects together .... code is https://pastebin.com/d8miuJDt (start to become long for direct mail pasting?) i can run the file fine with just one of the parts of the beak, but as soon as i activate both, i either get UI-WARNING: No top level geometry to render or this one: ERROR: CGAL error in CGAL_Nef_polyhedron3(): CGAL ERROR: assertion violation! Expr: e->incident_sface() != SFace_const_handle() File: /usr/include/CGAL/Nef_S2/SM_const_decorator.h Line: 330 ERROR: CGAL error in CGAL_Nef_polyhedron3(): CGAL ERROR: assertion violation! Expr: e->incident_sface() != SFace_const_handle() File: /usr/include/CGAL/Nef_S2/SM_const_decorator.h Line: 330 what's going wrong? a fix? -- ciao Bruno =========================================== http://nohkumado.eu/, <http://bboett.free.fr>http://aikido.nohkumado.eu/, <http://bboett.free.fr> http://aikido.zorn.free.fr

Does your swept shape self intersect? On Fri, 22 May 2020 at 16:33, Bruno Boettcher <bboett@gmail.com> wrote: > hello! > > > i progressed with my dragon... i used the Naca sweep from parkingbot, with > excellent results, until.... i tried to put 2 sweeped objects together .... > > code is https://pastebin.com/d8miuJDt (start to become long for direct > mail pasting?) > > i can run the file fine with just one of the parts of the beak, but as > soon as i activate both, i either get > > UI-WARNING: No top level geometry to render > > or this one: > > ERROR: CGAL error in CGAL_Nef_polyhedron3(): CGAL ERROR: assertion > violation! Expr: e->incident_sface() != SFace_const_handle() File: > /usr/include/CGAL/Nef_S2/SM_const_decorator.h Line: 330 > > ERROR: CGAL error in CGAL_Nef_polyhedron3(): CGAL ERROR: assertion > violation! Expr: e->incident_sface() != SFace_const_handle() File: > /usr/include/CGAL/Nef_S2/SM_const_decorator.h Line: 330 > > > what's going wrong? a fix? > > -- > ciao > Bruno > > =========================================== > http://nohkumado.eu/, <http://bboett.free.fr>http://aikido.nohkumado.eu/, > <http://bboett.free.fr> > http://aikido.zorn.free.fr > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >

each polygon is separated by a step prior to the sweep? i don't think so, don't know if images go through, i try to send 2 pictures, one overall, one of the point that might intersect, but even on the point you see that there is, even if only slight, an offset between the polygons? but i might be wrong... ciao Bruno Am Fr., 22. Mai 2020 um 17:43 Uhr schrieb nop head <nop.head@gmail.com>: > Does your swept shape self intersect? > > On Fri, 22 May 2020 at 16:33, Bruno Boettcher <bboett@gmail.com> wrote: > >> hello! >> >> >> i progressed with my dragon... i used the Naca sweep from parkingbot, >> with excellent results, until.... i tried to put 2 sweeped objects together >> .... >> >> code is https://pastebin.com/d8miuJDt (start to become long for direct >> mail pasting?) >> >> i can run the file fine with just one of the parts of the beak, but as >> soon as i activate both, i either get >> >> UI-WARNING: No top level geometry to render >> >> or this one: >> >> ERROR: CGAL error in CGAL_Nef_polyhedron3(): CGAL ERROR: assertion >> violation! Expr: e->incident_sface() != SFace_const_handle() File: >> /usr/include/CGAL/Nef_S2/SM_const_decorator.h Line: 330 >> >> ERROR: CGAL error in CGAL_Nef_polyhedron3(): CGAL ERROR: assertion >> violation! Expr: e->incident_sface() != SFace_const_handle() File: >> /usr/include/CGAL/Nef_S2/SM_const_decorator.h Line: 330 >> >> >> what's going wrong? a fix? >> >> -- >> ciao >> Bruno >> >> =========================================== >> http://nohkumado.eu/, <http://bboett.free.fr>http://aikido.nohkumado.eu/, >> <http://bboett.free.fr> >> http://aikido.zorn.free.fr >> _______________________________________________ >> OpenSCAD mailing list >> Discuss@lists.openscad.org >> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >> > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org > -- ciao Bruno =========================================== http://nohkumado.eu/, <http://bboett.free.fr>http://aikido.nohkumado.eu/, <http://bboett.free.fr> http://aikido.zorn.free.fr

When you sweep a polygon along a path it is very easy to create a self intersection. If the gap between each section is small compared to the size of the 2D polygon then the curve cannot be sharp or the polygons collide. On Fri, 22 May 2020 at 17:36, Bruno Boettcher <bboett@gmail.com> wrote: > each polygon is separated by a step prior to the sweep? > i don't think so, don't know if images go through, i try to send 2 > pictures, one overall, one of the point that might intersect, but even on > the point you see that there is, even if only slight, an offset between the > polygons? > > but i might be wrong... > > ciao > Bruno > > > Am Fr., 22. Mai 2020 um 17:43 Uhr schrieb nop head <nop.head@gmail.com>: > >> Does your swept shape self intersect? >> >> On Fri, 22 May 2020 at 16:33, Bruno Boettcher <bboett@gmail.com> wrote: >> >>> hello! >>> >>> >>> i progressed with my dragon... i used the Naca sweep from parkingbot, >>> with excellent results, until.... i tried to put 2 sweeped objects together >>> .... >>> >>> code is https://pastebin.com/d8miuJDt (start to become long for direct >>> mail pasting?) >>> >>> i can run the file fine with just one of the parts of the beak, but as >>> soon as i activate both, i either get >>> >>> UI-WARNING: No top level geometry to render >>> >>> or this one: >>> >>> ERROR: CGAL error in CGAL_Nef_polyhedron3(): CGAL ERROR: assertion >>> violation! Expr: e->incident_sface() != SFace_const_handle() File: >>> /usr/include/CGAL/Nef_S2/SM_const_decorator.h Line: 330 >>> >>> ERROR: CGAL error in CGAL_Nef_polyhedron3(): CGAL ERROR: assertion >>> violation! Expr: e->incident_sface() != SFace_const_handle() File: >>> /usr/include/CGAL/Nef_S2/SM_const_decorator.h Line: 330 >>> >>> >>> what's going wrong? a fix? >>> >>> -- >>> ciao >>> Bruno >>> >>> =========================================== >>> http://nohkumado.eu/, <http://bboett.free.fr>http://aikido.nohkumado.eu/, >>> <http://bboett.free.fr> >>> http://aikido.zorn.free.fr >>> _______________________________________________ >>> OpenSCAD mailing list >>> Discuss@lists.openscad.org >>> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >>> >> _______________________________________________ >> OpenSCAD mailing list >> Discuss@lists.openscad.org >> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >> > > > -- > ciao > Bruno > > =========================================== > http://nohkumado.eu/, <http://bboett.free.fr>http://aikido.nohkumado.eu/, > <http://bboett.free.fr> > http://aikido.zorn.free.fr > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >