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naca sweep, doubling up and ERROR: CGAL error in CGAL_Nef_polyhedron3(): CGAL ERROR: assertion violation!

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bboett

naca sweep, doubling up and ERROR: CGAL error in CGAL_Nef_polyhedron3(): CGAL ERROR: assertion violation!

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

what's going wrong? a fix?

ciao
Bruno

===========================================
http://nohkumado.eu/, http://aikido.nohkumado.eu/,
http://aikido.zorn.free.fr

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nophead

Re: naca sweep, doubling up and ERROR: CGAL error in CGAL_Nef_polyhedron3(): CGAL ERROR: assertion violation!

Does your swept shape self intersect?

On Fri, 22 May 2020 at 16:33, Bruno Boettcher <[hidden email]> 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://aikido.nohkumado.eu/,
http://aikido.zorn.free.fr
_______________________________________________
OpenSCAD mailing list
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bboett

Re: naca sweep, doubling up and ERROR: CGAL error in CGAL_Nef_polyhedron3(): CGAL ERROR: assertion violation!

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 <[hidden email]>:

Does your swept shape self intersect?

On Fri, 22 May 2020 at 16:33, Bruno Boettcher <[hidden email]> 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://aikido.nohkumado.eu/,
http://aikido.zorn.free.fr
_______________________________________________
OpenSCAD mailing list
[hidden email]
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

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ciao
Bruno

===========================================
http://nohkumado.eu/, http://aikido.nohkumado.eu/,
http://aikido.zorn.free.fr

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nophead

Re: naca sweep, doubling up and ERROR: CGAL error in CGAL_Nef_polyhedron3(): CGAL ERROR: assertion violation!

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 <[hidden email]> 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 <[hidden email]>:
Does your swept shape self intersect?

On Fri, 22 May 2020 at 16:33, Bruno Boettcher <[hidden email]> 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://aikido.nohkumado.eu/,
http://aikido.zorn.free.fr
_______________________________________________
OpenSCAD mailing list
[hidden email]
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

_______________________________________________
OpenSCAD mailing list
[hidden email]
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

--
ciao
Bruno

===========================================
http://nohkumado.eu/, http://aikido.nohkumado.eu/,
http://aikido.zorn.free.fr
_______________________________________________
OpenSCAD mailing list
[hidden email]
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

_______________________________________________
OpenSCAD mailing list
[hidden email]
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org