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Tetrahedron center
Posted: 21 March 2013 08:15 PM   [ Ignore ]
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Is there a way to have the tetrahedron’s central axis point actually be in its center. When I create the object, then rotate it, it rotates asymmetrically. Regardless of setting it to ‘Center’ or ‘Basis’ or making other changes.

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Posted: 21 March 2013 11:10 PM   [ Ignore ]   [ # 1 ]
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The pivot point is located at the centre of the surrounding box, which in the case of the tetrahedron is off-centre of the mesh.

You can set the pivot point to anywhere you want it to be, as long as it is a vert,  by right-clicking and selecting “Set pivot point”.  So you would need to either cut in some edges to get a vert located at the centre, or you can make a facet, place it so that one of the verts is at the centre-point and set the pivot point to that.

Bit of a nuisance, but not that difficult to do:)

Be aware, though, that when you take the mesh into a rendering app, it will not respect the re-set pivot point and will set it to the centre of the bounding box.  So, changing a pivot point is only useful during the modeling process and won’t be of any use further down the line in the animation process.

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Posted: 22 March 2013 06:47 AM   [ Ignore ]   [ # 2 ]
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Thanks Roygee! It didn’t make sense to me until you explained it that way.

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Posted: 22 March 2013 07:12 AM   [ Ignore ]   [ # 3 ]
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Oh what fun, so where is the centre of a tetrahedron ?

Roy, no, don’t even go there smile

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Posted: 22 March 2013 07:15 AM   [ Ignore ]   [ # 4 ]
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Hi ragaray,

You can create the Tetrahedron from its center (see right hand side options), so you can snap to a vertex when creating.
Once created, use the “set pivot point” and snap the pivot back to creation center.

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