Is there any easy way to compute the volume of an OpenSCAD object? I am
making molds, and wonder if OpenSCAD can tell me how much material to
prepare for a casting.

Jon

below you can find the formula to calculate the volume from the triangles (faces). I am not a programmer, but skilled enough to test it with Javascript. It works fine but I can't put it inside OpenScad. If somebody could implement it, it would be fine to see the result not only as part of the message window, but also offering the opportunity to export the result in any way, so I can make use of it in our software.

/xyz=[
0, 0, 3000,
5000, 0, 3000,
5000, 200, 3000,
0, 200, 3000,
0, 200, 0,
5000, 200, 0,
5000, 0, 0,
0, 0, 0,
1000, 200, 0,
2000, 200, 0,
1000, 0, 0,
2000, 0, 0,
1000, 0, 2000,
2000, 0, 2000,
1000, 200, 2000,
2000, 200, 2000];
p=[
7, 0, 4,
4, 0, 3,
0, 7, 10,
13, 0, 12,
12, 0, 10,
1, 0, 13,
6, 13, 11,
1, 13, 6,
7, 4, 10,
10, 4, 8,
4, 3, 8,
15, 3, 2,
9, 2, 5,
14, 3, 15,
8, 3, 14,
15, 2, 9,
3, 0, 1,
2, 3, 1,
1, 6, 5,
2, 1, 5,
11, 9, 6,
6, 9, 5,
15, 9, 13,
13, 9, 11,
15, 13, 14,
14, 13, 12,
8, 14, 12,
10, 8, 12];/
xyz=[
0, 0, 3000,
5000, 0, 3000,
5000, 200, 3000,
0, 200, 3000,
0, 200, 0,
5000, 200, 0,
5000, 0, 0,
0, 0, 0,
1000, 0,2000,
1000, 0, 1000,
3000, 0, 2000,
3000, 0, 1000,
1000, 200, 2000,
1000, 200, 1000,
3000, 200, 2000,
3000, 200, 1000];
p=[
7, 0, 4,
4, 0, 3,
9, 7, 6,
11, 9, 6,
0, 7, 9,
0, 9, 8,
1, 10, 6,
1, 0, 10,
10, 11, 6,
8, 10, 0,
7, 4, 6,
6, 4, 5,
14, 3, 2,
4, 3, 12,
13, 15, 5,
4, 12, 13,
4, 13, 5,
5, 14, 2,
12, 3,14,
14, 5, 15,
3, 0, 1,
2, 3, 1,
1, 6, 5,
2, 1, 5,
13, 12, 8,
9, 13, 8,
11, 15, 13,
9, 11, 13,
14, 15, 10,
10, 15, 11,
14, 10, 12,
12, 10, 8];
j=0;k=(p.length)/3;Vol=0.0;console.log(k);
for (var i=0;i<k;i++) {
console.log(j,'=j',p[j],p[j+1],p[j+2]);
p1x=xyz[p[j]3+0];p2x=xyz[p[j+1]3+0];p3x=xyz[p[j+2]3+0];
p1y=xyz[p[j]3+1];p2y=xyz[p[j+1]3+1];p3y=xyz[p[j+2]3+1];
p1z=xyz[p[j]3+2];p2z=xyz[p[j+1]3+2];p3z=xyz[p[j+2]3+2];
var v321 = p3xp2yp1z;
var v231 = p2xp3yp1z;
var v312 = p3xp1yp2z;
var v132 = p1xp3yp2z;
var v213 = p2xp1yp3z;
var v123 = p1xp2y*p3z;
v=(-v321 + v231 + v312 - v132 - v213 + v123)/6;
console.log('p1',p1x,p1y,p1z,'p2',p2x,p2y,p2z,'p3',p3x,p3y,p3z,'v',v);
j=j+3;Vol=Vol+v; }
console.log(Vol);

Kind regards
Wolfgang Ehlert

-----Ursprüngliche Nachricht-----
Von: Discuss [mailto:discuss-bounces@lists.openscad.org] Im Auftrag von jon
Gesendet: Montag, 29. Dezember 2014 14:49
An: discuss@lists.openscad.org
Betreff: [OpenSCAD] volume measurements

Is there any easy way to compute the volume of an OpenSCAD object? I am making molds, and wonder if OpenSCAD can tell me how much material to prepare for a casting.

Jon

OpenSCAD mailing list
Discuss@lists.openscad.org
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

Cheat's way:  Open it in a slicer for 3d printing, set to 100% infill, no
raft, brim or support, and from the estimate of quantity of filament used,
get the volume...

-----Original Message-----
From: Discuss [mailto:discuss-bounces@lists.openscad.org] On Behalf Of
Ehlert, Wolfgang
Sent: 29 December 2014 14:10
To: OpenSCAD general discussion
Subject: Re: [OpenSCAD] volume measurements

below you can find the formula to calculate the volume from the triangles
(faces). I am not a programmer, but skilled enough to test it with
Javascript. It works fine but I can't put it inside OpenScad. If somebody
could implement it, it would be fine to see the result not only as part of
the message window, but also offering the opportunity to export the result
in any way, so I can make use of it in our software.

/xyz=[
0, 0, 3000,
5000, 0, 3000,
5000, 200, 3000,
0, 200, 3000,
0, 200, 0,
5000, 200, 0,
5000, 0, 0,
0, 0, 0,
1000, 200, 0,
2000, 200, 0,
1000, 0, 0,
2000, 0, 0,
1000, 0, 2000,
2000, 0, 2000,
1000, 200, 2000,
2000, 200, 2000];
p=[
7, 0, 4,
4, 0, 3,
0, 7, 10,
13, 0, 12,
12, 0, 10,
1, 0, 13,
6, 13, 11,
1, 13, 6,
7, 4, 10,
10, 4, 8,
4, 3, 8,
15, 3, 2,
9, 2, 5,
14, 3, 15,
8, 3, 14,
15, 2, 9,
3, 0, 1,
2, 3, 1,
1, 6, 5,
2, 1, 5,
11, 9, 6,
6, 9, 5,
15, 9, 13,
13, 9, 11,
15, 13, 14,
14, 13, 12,
8, 14, 12,
10, 8, 12];/
xyz=[
0, 0, 3000,
5000, 0, 3000,
5000, 200, 3000,
0, 200, 3000,
0, 200, 0,
5000, 200, 0,
5000, 0, 0,
0, 0, 0,
1000, 0,2000,
1000, 0, 1000,
3000, 0, 2000,
3000, 0, 1000,
1000, 200, 2000,
1000, 200, 1000,
3000, 200, 2000,
3000, 200, 1000];
p=[
7, 0, 4,
4, 0, 3,
9, 7, 6,
11, 9, 6,
0, 7, 9,
0, 9, 8,
1, 10, 6,
1, 0, 10,
10, 11, 6,
8, 10, 0,
7, 4, 6,
6, 4, 5,
14, 3, 2,
4, 3, 12,
13, 15, 5,
4, 12, 13,
4, 13, 5,
5, 14, 2,
12, 3,14,
14, 5, 15,
3, 0, 1,
2, 3, 1,
1, 6, 5,
2, 1, 5,
13, 12, 8,
9, 13, 8,
11, 15, 13,
9, 11, 13,
14, 15, 10,
10, 15, 11,
14, 10, 12,
12, 10, 8];
j=0;k=(p.length)/3;Vol=0.0;console.log(k);
for (var i=0;i<k;i++) {
console.log(j,'=j',p[j],p[j+1],p[j+2]);
p1x=xyz[p[j]3+0];p2x=xyz[p[j+1]3+0];p3x=xyz[p[j+2]3+0];
p1y=xyz[p[j]3+1];p2y=xyz[p[j+1]3+1];p3y=xyz[p[j+2]3+1];
p1z=xyz[p[j]3+2];p2z=xyz[p[j+1]3+2];p3z=xyz[p[j+2]3+2];
var v321 = p3xp2yp1z;
var v231 = p2xp3yp1z;
var v312 = p3xp1yp2z;
var v132 = p1xp3yp2z;
var v213 = p2xp1yp3z;
var v123 = p1xp2y*p3z;
v=(-v321 + v231 + v312 - v132 - v213 + v123)/6;

console.log('p1',p1x,p1y,p1z,'p2',p2x,p2y,p2z,'p3',p3x,p3y,p3z,'v',v);
j=j+3;Vol=Vol+v; }
console.log(Vol);

Kind regards
Wolfgang Ehlert

-----Ursprüngliche Nachricht-----
Von: Discuss [mailto:discuss-bounces@lists.openscad.org] Im Auftrag von jon
Gesendet: Montag, 29. Dezember 2014 14:49
An: discuss@lists.openscad.org
Betreff: [OpenSCAD] volume measurements

Is there any easy way to compute the volume of an OpenSCAD object? I am
making molds, and wonder if OpenSCAD can tell me how much material to
prepare for a casting.

Jon

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

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