Beginner. Voronoi Cube.

[olishea]

Hello,

Please be tame I'm a beginner with Wings.

I'm interested in a voronoi workflow, applying the tessellation to different 3D forms.

I practiced using the Sauermann tutorial, using boolean tool to intersect the voronoi objects with a cube. While it worked out correctly, it wasn't exactly the result I was looking for.

I have to explode the voronoi elements by 1% in order for them to intersect with the cube. This results in an offset voronoi pattern, where I just want a single line to divide the shapes. Is there any way I can just intersect the voronoi elements with a cube without having to explode them? So the lines are "etched" into the cube?

Basically all I want is a cube with a voronoi pattern ON THE SURFACE. I understand there might be a voronoi primitive but I need to learn how to apply this to other shapes. The lines on the cube must break it up into individual faces, like they are actually intersected....just like the voronoi sphere primitive (how do you get to that?)

Hope this makes sense! It's probably a very easy thing to do haha

Sorry if some of my terminology is off! Any help very much appreciated.

I attached a screenshot of what I'm trying to achieve.

[ggaliens]

Step 1 is to find any too to make "adaptive isotropic remesh"
Of your surface. GEEK-SPEAK ... but is needed for best result.

Basically ... you need to triangulate your mesh in a nice way that can produce
a nice DUAL voronoi. Currently manifoldlab does not help you with that
starting mesh. Sorry to tell you that.

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Where I left off ...

Was that in order to get a VORONOI foamy version of your somewhat arbitrary model ....

1) You have to do the adaptive isotropic remesh of surface.
2) Tet the entire thing asking tetgen to obey the surface mesh
(don't divide the surface ... just interior)
3) Use these tets as "SITES" for QHULL.
4) take SPIKEY output from (3) and use CarveCSG to trim the spikes to original mesh.

Truth be told ... the general case application implied above has evolved into something that needs to be documented in a PDF ... and something that has not been tested on Mac yet ... and would probably require some work to get going on a Mac.

So ... ManifoldLab does help with all these steps ... but it makes not attempt to document them or role them into an easy to use macro. And is usually done first on Windows platforms.

I went hunting in my video playlists to try to find the last best video that could show many of the steps.

Bottom line ... very easy to forget the scope of what commands are needed.

Some people have "leap-frogged me" in terms of getting lemonade out of these lemons ... but very few. You have to pick a version of mlab and stick with it ... or have a very open dialog with me and some patience.

[ggaliens]

In order to get a good foamy result ... you must start with something a bit like ...
(but make all the arcs into straight lines ... flat triangles).


http://www-sop.inria.fr/prisme/telegeo/workshop/max.jpg

You can generate these meshes with other tools ... but it seems like black magic to me ...

It is even a bit hard to do right with tools like MESHLAB.

[olishea]

Thanks.

"1) You have to do the adaptive isotropic remesh of surface"

Erm....how do I do this? haha

4) take SPIKEY output from (3) and use CarveCSG to trim the spikes to original mesh.

Where can I find Carve?

Sorry I thought this would be quite simple! I'm making "celled" or voronoi shapes for 3D printing and found I'm getting really close in wings, but it's not what I want yet. I had some good results in meshlab but I really enjoy using wings. The idea is to make some "chicken wire" sculptures/products.

I nearly got a voronoi torus, but same problem again, the lines aren't intersected into the original torus and there is internal geometry.

Thanks for the reply, I just don't understand what you mean! I'm a complete newbie at wings! I hope you are patient lol

[olishea]

I have shared a link where you can download the cube I'm having trouble with.

https://app.box.com/s/3jfnkxo61scht9x8ilge

How do I just delete the internal geometry?

Is it possible to use this method on any shape object?

I have seen your rabbit example, but it still has geometry on the inside. All I want is a hollow object with the voronoi edges on its surface. I have tried everything, but it just feels like I'm pressing random buttons now lol

When I have my hollow "voronoied" object, I can then use inset and intrude on the faces to create an interesting model.

I managed to get some results with meshlab, but I'd rather nail this in wings.

Here is a model that I've meshed with a voronoi pattern in meshlab.

[ggaliens]

A video tutorial / guide


https://www.youtube.com/watch?v=xUPDnzRM...e=youtu.be

[olishea]

This is amazing feedback. Thank you for being so thoughtful. I will donate at the end of the month to show my gratitude. I'll let you know how I get on with other shapes too.

Thanks again, I totally didn't expect a reply let alone a video tutorial.

Thumbs up for great support!!

Just playing with some of your other tutorials too....and I'm getting to some really interesting shapes. Perfect for 3D printing. If my cutter is relatively simple, I can get some pretty funky geometry, loving it!!

I know there are too many poles, but it's just a practice model. I'm also trying to do this with a torus but using it as polyhedra cutter doesn't seem to work....I'll keep on it!

The idea is to take any printable solid, and transform it into an organic mesh which reduces the amount of material used in the 3D printing process. Not only does it catch the eye, it vastly reduces manufacture costs while allowing the potential for more flexible designs.

[olishea]

Right. Next question.

I have a torus where I have performed "voronoi encrust surface".

I can not use polyhedra as cutter as it just leaves a little UFO looking disc in the middle. I used polyhedra as cutter to make the voronoi cube you worked on.

It won't let me use boolean as the tidbits are not exploded outwards.

See screenshot, this is where I'm at....lots of Tidbits coming out of the torus.

Again, I want to "intersect" these shapes with the torus leaving only the edges on the torus's surface. No internal geometry, just a torus with edges.

Wings file:

https://app.box.com/s/ot54dikjtkvtfq1igpt3



This is almost what I'm trying to achieve. I just need the torus without all the gaps in it, only the edges are required. The torus has gaps between the cells because this was the only way I could intersect the Tidbits with the torus, by exploding, combining and then boolean. Any ideas?

[ggaliens]

Olishea ...

Meshlab does not do ADAPTIVE isotropic remeshing as far as you know ?
Correct ?

It would never retain mesh shape while resampling surface and laying out nice
somewhat pretty triangles on mesh. Isotropic just means somewhat similar edges
sizes in triangle ... does not mean all equilaterals. Just nice ... not so many long triangles.

Adaptive means smaller triangles are used rather than slivers. We have been looking
for a CHEAPWARE app that does a nice job of this and have come to conclusion that a good
implementation is hard to find.

I did find 1 ... and had to FIX the code and compile it for my platform. It is a command line tool.

If you don't do the adaptive isotropic mesh remeshing for your initial mesh ... your trials and tribulations
in wings and manifoldlab will be numerous and tedious.

[ggaliens]

Does not require a "Coffin" to do the torus ... well ... not same kind of "coffin".

1) Make a heavy torus ... thicker and more stubby than you desire. Voronoi encrust volume with 1000 or more points not welding during process. Leave tidbits as separate.

2) Make a new torus with default + maybe 1 smooth. Use it as a CUTTER ... not with cut command but with a new boolean command that might not be on Mac. (Accumulate). It does intersect over and over serially.

3) Remove curtter object and combind new tidbits.

4) Select higher valance edges and then invert. The inverse is all the edges you didn't want that were projected by the cutter torus.

5) Select coincident faces and invert to get faces to STITCH into new manifold lab. Hide the faces that are in coincident pairs. Then stitch. This will almost always FAIL the first time you try it. Now is a good time to save your work.

6) Fly INSIDE your torus looking for faces that should have been removed as per coincident pairings but were not ... probably because of discrete match issues in Wings/MLAB. Remove them by hand uing hide. This is not easy .. but is quite doable with patience.

7) Run clean-up.

Stitch. If fails ... look HARD for a reason.

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https://www.youtube.com/watch?v=a8KjNk_1...e=youtu.be