# Computing the Dual With VEX

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mestela    451

Your gif is pleasing. It is a pleasing gif.

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Saber    46

Very nice, Thanks for sharing this and for the write up!

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Aw shucks! You guys are too kind

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rich_lord    161

Yeah this is great. Half edges are a bit of a mystery to me, but this makes them clearer. Thanks!

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Damn three of my favorite tech wizards all commenting on muh post!  Thanks for the kind words!!! Another thing I neglected to mention in the post is that the dual of delaunay triangle graph is a voronoi diagram, so really this can also be used as a vex method of generating voronoi diagrams. What that means for us is, assuming you run it on a mesh generated from "Triangulate 2D," you should get a voronoi diagram of the input points! Neat!

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petz    305
On 20.5.2017 at 2:13 AM, sweetdude09 said:

... the dual of delaunay triangle graph is a voronoi diagram ...

this isn't necessarily true and depends on which type of dual you are using. in case of houdins barycentric based dual for instance, it isn't true. if you wanna get voronoi cells you have to compute the circumcentric (voronoi) dual instead. in this case the dual is orthogonal to it's primal triangulation which is one of the key properties of a voronoi.

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Posted (edited)

Ah that's a very interesting distinction. After doing a bit more research it appears i need to compute the dual using the circumcenters of a deluanay triangulation in order to compute the dual. Radical, i might take a crack at that today since I have a bit of free time, will post result in a bit =)

Edited by sweetdude09
I'm a goober!

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I'm not sure if replying to myself is bad form, but here's a gif of the voronoi version. Big thanks to petz for sending me down the right path on this one =)

JR_VORONOI_WRANGLE.hip

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Posted (edited)

"But before we get into that, holy shit look at this baby tapir."

good one
Edited by cudarsjanis
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