Hexagonal mesh

[guache]

What's the quickest way to generate a surface divided into poly hexagons in Houdini? The edges between hexagons should be shared, not duplicated.

[sam.h]

http://www.google.com.au/url?sa=t&rct=j&q=arbitrary+hex+mesh&source=web&cd=4&ved=0CDkQFjAD&url=http%3A%2F%2Fresearch.microsoft.com%2Fen-us%2Fum%2Fpeople%2Fyangliu%2Fpublication%2Fa%2520note%2520on%2520planar%2520hexagonal%2520meshes.pdf&ei=YzDgTpKVEMnrrQfl4cmnCw&usg=AFQjCNGFand_fk4a_UiFloW2RUwfNCunkg

[guache]

Thanks. To be more clear: I don't need to divide an arbitrary 3D shape into hexagons, I just need a flat, roughly square surface made of hexagons. I can always use a Copy SOP, but I thought there could be a "smarter" way.

EDIT: Never mind, I got it: start with a tri grid, then blast away the centers of hexagonal areas.

Edited December 8, 2011 by guache

[sam.h]

You can use voronoi fracture to split a grid into hexes... although the only problem with this is you end up with bits on the edges that aren't hexes.

...

I think using a copy is a good way to do it

[sam.h]

You can use voronoi fracture to split a grid into hexes... although the only problem with this is you end up with bits on the edges that aren't hexes.

...

I think using a copy is a good way to do it

annnd here is the file

but I don't think the hexes are right ...

hexGrid.hip

[guache]

Thanks. The Voronoi hexes are a bit uneven. In Copy, a Z offset of 0.56 (rather than 0.5) gives better results. I'll try to fix the hexes by snapping to tri grid.

[edward]

http://www.google.co...FloW2RUwfNCunkg

Thanks for the link!

On a closed surface of genus 0, faces other than hexagons

must be used, provided that all the vertices are of degree 3 (for example,

see Figure 2). Assuming that only hexagons and pentagons are allowed,

it is easy to show that there have to be exactly 12 pentagons. A typical

soccer ball is an example of such a tiling of a surface of genus 0, which has

12 pentagons and 20 hexagons.

[Jason]

Interesting paper, thanks

[Ryan]

If you start with something with all triangles and use the Divide SOP with "Compute Dual" on, you can get some cool stuff.

Give this a try...

Grid SOP,

then PolyBevel SOP, with "Relative Inset" set to 1

then Divide SOP, with "Compute Dual"

Also take a look inside the Platonic Solid SOP and see how they created the Soccer Ball.

hexagonMesh_odforce.hip

Edited December 15, 2011 by Ryan

[nazar]

You can not use copy SOP, but move the second row of plane

[edward]

Also take a look inside the Platonic Solid SOP and see how they created the Soccer Ball.

Yes, except it's not really a "soccer" ball. A real soccer ball is a bucky ball, which I made an HDA for it awhile back:

http://www.sidefx.co....php?fileid=262

[guache]

Grid SOP,

then PolyBevel SOP, with "Relative Inset" set to 1

then Divide SOP, with "Compute Dual"

Very clean hexes, thanks.