My Asp exports as manifold, but the polyhedron breaks with Union.
I've been reading about manifold shapes, and welds, and such, and was able to
build 35 Elite ships that export without incident.
I've got 3 - the Asp here is one of them, and I can't get it to survive
being unioned with a cube. It becomes non-manifold.
I've checked with the "Thrown together" view for incorrect windings, and
there is none.
I've also checked that there's no polygons meeting midway along a long
edge... they all meet at vertices.
So as of this point, I've run out of things to check or try - if anyone
could confirm the shapes correct I can stop trying to fix it!
Many thanks!
//-----------------------------------------
polyhedron(
points=[
[115, -10, 15], // 0
[50, -10, 97], // 1
[90, 16, 27], // 2
[-50, -10, 97], // 3
[-115, -10, 15], // 4
[-90, 16, 27], // 5
[65, -10, -103], // 6
[98, -30, 37], // 7
[-98, -30, 37], // 8
[-65, -10, -103], // 9
[0, 30, -11], // 10
[0, 20, -103], // 11
[18, -10, -103] // 12
],
faces=[
[7,0,6], // a
[8,3,1,7], // b
[7,6,9,8], // c
[6,2,10], // d
[5,9,10], // e
[11,6,10], // f
[11,10,9], // g
[2,1,3,5,10], // h
[6,11,9,12], // i
[9,5,4], // j
[8,9,4], // k
[3,8,4], // l
[4,5,3], // m
[1,2,0], // n
[0,7,1], // o
[0,2,6] // p
]
);
translate([0,10,50]) cube(30, center=true);
--
Sent from: http://forum.openscad.org/
That is the problem, can't have a vertex in the middle of an edge.
-----Original Message-----
From: Discuss [mailto:discuss-bounces@lists.openscad.org] On Behalf Of SarahC
Sent: Sun, 8 Sep 2019 13:11
Subject: [OpenSCAD] My Asp exports as manifold, but the polyhedron breaks with Union.
I've been reading about manifold shapes, and welds, and such, and was able to
build 35 Elite ships that export without incident.
I've got 3 - the Asp here is one of them, and I can't get it to survive
being unioned with a cube. It becomes non-manifold.
I've checked with the "Thrown together" view for incorrect windings, and
there is none.
I've also checked that there's no polygons meeting midway along a long
edge... they all meet at vertices.
So as of this point, I've run out of things to check or try - if anyone
could confirm the shapes correct I can stop trying to fix it!
Many thanks!
//-----------------------------------------
polyhedron(
points=[
[115, -10, 15], // 0
[50, -10, 97], // 1
[90, 16, 27], // 2
[-50, -10, 97], // 3
[-115, -10, 15], // 4
[-90, 16, 27], // 5
[65, -10, -103], // 6
[98, -30, 37], // 7
[-98, -30, 37], // 8
[-65, -10, -103], // 9
[0, 30, -11], // 10
[0, 20, -103], // 11
[18, -10, -103] // 12
],
faces=[
[7,0,6], // a
[8,3,1,7], // b
[7,6,9,8], // c
[6,2,10], // d
[5,9,10], // e
[11,6,10], // f
[11,10,9], // g
[2,1,3,5,10], // h
[6,11,9,12], // i
[9,5,4], // j
[8,9,4], // k
[3,8,4], // l
[4,5,3], // m
[1,2,0], // n
[0,7,1], // o
[0,2,6] // p
]
);
translate([0,10,50]) cube(30, center=true);
--
Sent from: http://forum.openscad.org/
OpenSCAD mailing list
This email has been checked for viruses by AVG.
https://www.avg.com
How did I miss that?
Thank you so much! You are wonderful.
I hope this reply works - I'm replying to the email I received from the
message board, and I hope it ends up on the OpenSCAD forum pages.
On Sun, 8 Sep 2019 at 04:24, OzAtMichael oz.at.michael@gmail.com wrote:
That is the problem, can't have a vertex in the middle of an edge.
-----Original Message-----
From: Discuss [mailto:discuss-bounces@lists.openscad.org] On Behalf Of
SarahC
Sent: Sun, 8 Sep 2019 13:11
Subject: [OpenSCAD] My Asp exports as manifold, but the polyhedron
breaks with Union.
I've been reading about manifold shapes, and welds, and such, and was
able to
build 35 Elite ships that export without incident.
I've got 3 - the Asp here is one of them, and I can't get it to survive
being unioned with a cube. It becomes non-manifold.
I've checked with the "Thrown together" view for incorrect windings, and
there is none.
I've also checked that there's no polygons meeting midway along a long
edge... they all meet at vertices.
So as of this point, I've run out of things to check or try - if anyone
could confirm the shapes correct I can stop trying to fix it!
Many thanks!
//-----------------------------------------
polyhedron(
points=[
[115, -10, 15], // 0
[50, -10, 97], // 1
[90, 16, 27], // 2
[-50, -10, 97], // 3
[-115, -10, 15], // 4
[-90, 16, 27], // 5
[65, -10, -103], // 6
[98, -30, 37], // 7
[-98, -30, 37], // 8
[-65, -10, -103], // 9
[0, 30, -11], // 10
[0, 20, -103], // 11
[18, -10, -103] // 12
],
faces=[
[7,0,6], // a
[8,3,1,7], // b
[7,6,9,8], // c
[6,2,10], // d
[5,9,10], // e
[11,6,10], // f
[11,10,9], // g
[2,1,3,5,10], // h
[6,11,9,12], // i
[9,5,4], // j
[8,9,4], // k
[3,8,4], // l
[4,5,3], // m
[1,2,0], // n
[0,7,1], // o
[0,2,6] // p
]
);
translate([0,10,50]) cube(30, center=true);
--
Sent from: http://forum.openscad.org/
OpenSCAD mailing list
http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient Virus-free.
www.avg.com
http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient
<#m_8903485202599047183_DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
OpenSCAD mailing list
Discuss@lists.openscad.org
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org
Yes, that works. Email is good for inline images BTW, the forum 'changed' and just includes a link
to the image.
For debugging this stuff it is also handy to set View/Show-edges, in case you didn't see that
option.
From: Discuss [mailto:discuss-bounces@lists.openscad.org] On Behalf Of Sarah Cartwright
Sent: Sun, 8 Sep 2019 13:28
To: OpenSCAD general discussion
Subject: Re: [OpenSCAD] My Asp exports as manifold, but the polyhedron breaks with Union.
How did I miss that?
Thank you so much! You are wonderful.
I hope this reply works - I'm replying to the email I received from the message board, and I hope
it ends up on the OpenSCAD forum pages.
On Sun, 8 Sep 2019 at 04:24, OzAtMichael oz.at.michael@gmail.com wrote:
That is the problem, can't have a vertex in the middle of an edge.
-----Original Message-----
From: Discuss [mailto:discuss-bounces@lists.openscad.org] On Behalf Of SarahC
Sent: Sun, 8 Sep 2019 13:11
Subject: [OpenSCAD] My Asp exports as manifold, but the polyhedron breaks with Union.
I've been reading about manifold shapes, and welds, and such, and was able to
build 35 Elite ships that export without incident.
I've got 3 - the Asp here is one of them, and I can't get it to survive
being unioned with a cube. It becomes non-manifold.
I've checked with the "Thrown together" view for incorrect windings, and
there is none.
I've also checked that there's no polygons meeting midway along a long
edge... they all meet at vertices.
So as of this point, I've run out of things to check or try - if anyone
could confirm the shapes correct I can stop trying to fix it!
Many thanks!
//-----------------------------------------
polyhedron(
points=[
[115, -10, 15], // 0
[50, -10, 97], // 1
[90, 16, 27], // 2
[-50, -10, 97], // 3
[-115, -10, 15], // 4
[-90, 16, 27], // 5
[65, -10, -103], // 6
[98, -30, 37], // 7
[-98, -30, 37], // 8
[-65, -10, -103], // 9
[0, 30, -11], // 10
[0, 20, -103], // 11
[18, -10, -103] // 12
],
faces=[
[7,0,6], // a
[8,3,1,7], // b
[7,6,9,8], // c
[6,2,10], // d
[5,9,10], // e
[11,6,10], // f
[11,10,9], // g
[2,1,3,5,10], // h
[6,11,9,12], // i
[9,5,4], // j
[8,9,4], // k
[3,8,4], // l
[4,5,3], // m
[1,2,0], // n
[0,7,1], // o
[0,2,6] // p
]
);
translate([0,10,50]) cube(30, center=true);
--
Sent from: http://forum.openscad.org/
OpenSCAD mailing list
<http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_con
tent=emailclient>
Virus-free.
<http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_con
tent=emailclient> www.avg.com
OpenSCAD mailing list
Discuss@lists.openscad.org
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org
This email has been checked for viruses by AVG.
https://www.avg.com
I forgot it had "Show edges" - Thanks!
On Sun, 8 Sep 2019 at 04:44, OzAtMichael oz.at.michael@gmail.com wrote:
Yes, that works. Email is good for inline images BTW, the forum 'changed'
and just includes a link to the image.
For debugging this stuff it is also handy to set View/Show-edges, in case
you didn't see that option.
From: Discuss [mailto:discuss-bounces@lists.openscad.org] *On Behalf Of
*Sarah Cartwright
Sent: Sun, 8 Sep 2019 13:28
To: OpenSCAD general discussion
Subject: Re: [OpenSCAD] My Asp exports as manifold, but the polyhedron
breaks with Union.
How did I miss that?
Thank you so much! You are wonderful.
I hope this reply works - I'm replying to the email I received from the
message board, and I hope it ends up on the OpenSCAD forum pages.
On Sun, 8 Sep 2019 at 04:24, OzAtMichael oz.at.michael@gmail.com wrote:
That is the problem, can't have a vertex in the middle of an edge.
-----Original Message-----
From: Discuss [mailto:discuss-bounces@lists.openscad.org] On Behalf Of
SarahC
Sent: Sun, 8 Sep 2019 13:11
Subject: [OpenSCAD] My Asp exports as manifold, but the polyhedron
breaks with Union.
I've been reading about manifold shapes, and welds, and such, and was
able to
build 35 Elite ships that export without incident.
I've got 3 - the Asp here is one of them, and I can't get it to survive
being unioned with a cube. It becomes non-manifold.
I've checked with the "Thrown together" view for incorrect windings, and
there is none.
I've also checked that there's no polygons meeting midway along a long
edge... they all meet at vertices.
So as of this point, I've run out of things to check or try - if anyone
could confirm the shapes correct I can stop trying to fix it!
Many thanks!
//-----------------------------------------
polyhedron(
points=[
[115, -10, 15], // 0
[50, -10, 97], // 1
[90, 16, 27], // 2
[-50, -10, 97], // 3
[-115, -10, 15], // 4
[-90, 16, 27], // 5
[65, -10, -103], // 6
[98, -30, 37], // 7
[-98, -30, 37], // 8
[-65, -10, -103], // 9
[0, 30, -11], // 10
[0, 20, -103], // 11
[18, -10, -103] // 12
],
faces=[
[7,0,6], // a
[8,3,1,7], // b
[7,6,9,8], // c
[6,2,10], // d
[5,9,10], // e
[11,6,10], // f
[11,10,9], // g
[2,1,3,5,10], // h
[6,11,9,12], // i
[9,5,4], // j
[8,9,4], // k
[3,8,4], // l
[4,5,3], // m
[1,2,0], // n
[0,7,1], // o
[0,2,6] // p
]
);
translate([0,10,50]) cube(30, center=true);
--
Sent from: http://forum.openscad.org/
OpenSCAD mailing list
Virus-free. www.avg.com
http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient
<#m_-562761674247115441_m_8903485202599047183_DAB4FAD8-2DD7-40B>
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
On 2019-09-08 05:10, SarahC wrote:
I've been reading about manifold shapes, and welds, and such, and was
able to
build 35 Elite ships that export without incident.
I've got 3 - the Asp here is one of them, and I can't get it to survive
being unioned with a cube. It becomes non-manifold.
The other replies to your question are correct, you have a vertex in the
middle of an edge, causing the polyhedron to be non-manifold. The actual
bug here is that such issues are not detected by OpenSCAD before export,
it will result in an STL that cannot be safely imported later. In other
words, if you suspect no issue and export the polyhedron (without the
union), and later import it and then try some boolean operation...
import("Asp.stl");
translate([0,10,50]) cube(30, center=true);
it will cause a warning:
WARNING: Object may not be a valid 2-manifold and may need repair!
The best fix is to make sure the polyhedron is correct in the first
place. However, if the STL came from some other source than your own
code you might be out of luck using it. One way of fixing such issues
without access to the source code is to run one of the repair utilities
that exist, for example "polyfix" that I wrote. It is part of the
AngelCAD package https://arnholm.github.io/angelcad-docs/ . When used on
this case, the problem is fixed:
C:\work\STL>polyfix Asp.stl
Parameters:
input_file = Asp.stl
iteration 0: vertices=63 faces=21
warning: nonmanifold edges: uc(1)=63
merged 50 vertices
split 1 face
total changes=51
no warnings
iteration 1: vertices=13 faces=22
total changes=0
no warnings
Summary:
polyhedron 0: vertices=13 faces=22 : no warnings
Writing: Asp_1.stl
... polyfix finished, time used: 0d 00h 00m 01s
In short, the vertex in the middle of the edge is detected, the edge and
relevant face(s) are split, creating a proper 2-manifold polyhedron. You
can then use the repaired STL in OpenSCAD without the warning:
import("Asp_1.stl");
translate([0,10,50]) cube(30, center=true);
Carsten Arnholm