AntiPrism

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 From:  bemfarmer
7583.1 
An antiprism is a uniform polyhedron consisting of 2 n-gon faces, rotated with respect to each other, connected by 2n equilateral triangles. With practice, these antiprisms can easily be constructed by using Moi interactively. The height can be constructed.

https://en.wikipedia.org/wiki/Antiprism

So far, this antiprism script creates only the vertex points, or else only a polyline of portions of the side triangles.
The minimum n-gon Side number is 2, which yields tetrahedron vertices. This "n-gon" is "degenerate".
An n-gon Side number of 3, yields octahedron vertices.

Possible improvements:
1. Use polygon factory to add top and bottom faces.
2. Modify the script to create the triangular side faces, and/or top and bottom faces.
3. Use circular array.
3. Add code for a 3D convex hull, such as 3D Gift Wrap algorithm. This would be very useful.

- Brian

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 From:  MarkRG (MARKRG0)
7583.2 In reply to 7583.1 
Just a warning that prisms and antiprisms should never be modelled in the same file. If the vertices touch, they will annihilate the operating system and destroy life as we know it - possibly.

M
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 From:  bemfarmer
7583.3 In reply to 7583.2 
Thank you for the caution, Mark.
Prisms can be made by extrusion. For a rectangular one, I usually call it a box.
Faces of 3D polygons are also called facets.
- B
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 From:  bemfarmer
7583.4 
Added two triangles. User can just Array Circular them, from the center point, to get all of the side triangles.
Top and bottom n-gons can easily be added using Polygon Edge.

Doing Array Circular with 2X n-gon value, with some trim and internal deletions, can be done.

- Brian



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