The task is to create a diamond covered surface for a pendant very similar to the image attached
with the golden frog. How a diamond "pave" looks like is shown in the second image. The geometric
pattern behind it is a honeycomb like grid.

I wonder if there is a workaround in MOI to solve this task for any kind of surfaces - I know of the
great little script "array gem", but in this case the gems should be arranged on a surface and not
only a curve.

Any idea how to come closer to a solution is very much appreciated ! TOM


Rhino offers an automates solution for that surface :
> https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3D5F7fP8eB2es&psig=AOvVaw2D807RGURVUQtCJcORM8cm&ust=1607599295766000&source=images&cd=vfe&ved=0CAMQjB1qFwoTCKCb3aDowO0CFQAAAAAdAAAAABAE

Hi Tom,
Three things come to mind.
Voronoi script, Delaunay script, and Hex grid node.

There were also some circle packing posts.

- Brian

Thank you Brian, Ill do search for those tools

Hi Tom, sorry I don't know of a good general purpose way to do that in MoI. It's not really the sort of thing that has a simple solution, it's a complex type of fitting process.

Your best bet is probably to use one of the specialized jewelry plug-ins for Rhino to do that, like the example that you show above. I think there is another one called RhinoGold too.

- Michael

Circa 2009, http://www.geometrie.tugraz.at/wallner/packing.pdf has nice pictures.
- - - - -

Would be a tough project.
Dynamic circle packing, fixed radii, certainly an advanced coding IMHO.

Hex, uniform triangle mesh the surface, and place a circle in each triangle...for a static covering...

-Brian

I not to happy about needing Rhino plus Rhinogold for just one project
so I am still thinking about a way managing it within MOI.

Great PDF ! Unfortunately I am no math wizard to cook up a tool.
I am also working with Cinema 4D which has a Cloner tool but
nothing about packing circles in that way. So maybe I will restricz
the design to the possibilites MOI offers within the ArrayGem script.

Brian, I did a MOI search for circle packing and hex script without results,
could you please point me to the threads you mentioned ? Thank you !

Hi Tom,

It is morning here. I'll have a look later for some posts on circle pack and hex mesh. The hex mesh was in posts/ nodes of James. Also in conformal map to torus.

-Brian

Do you have the diameter of gems, and model of frog's back?

Tablet has limited web functionality.

Regular MoI array command could array points/circles in hex layout, on a plane.
Unwrap frog back... Discard points outside of flat-back surface. Flow to 3D frog back. Copy gems to points.??????

-Brian

Hi Brian. The Frog is just an example to illustrate what I meant.
Diameter will be around 2 mm upwards.

Unwrapping is one method I thought of. In combination with drawing a hexagonal grid.

Here is a copy of the node program I did in ~2019.
The Macro goes in the nodeeditor macro directory.
The Demo goes in whatever node programs folder that the user wants.

So many old versions and incomplete versions, and a few missing node mods, and hard drive failure, makes it hard to sort out the good nodes.

James' macro was hexTesselation.nod, per memory.

- Brian

The hex centerpoints could be flowed onto the frogback surface.
One gem could then be copied to each new point on the frogback, but the gem would need a normal,
and each mapped point on the frogback would need a surface normal, to sit normal or tangent to the surface.
Also, I do not recall any batch copy of an object to multiple points.
Maybe a script could be written...

Starting to get into Mesh programming, rather than Nurbs.

The Rhino Pave video looks nice. Must have been a very involved programming effort...physics...

As I recall, forum references to circle packing likely not be of much benefit, so no more looking.

Came across a lot of conformal mapping papers, mostly inscrutable, but grist for new scripts...

Hi Tom,

re:
> I not to happy about needing Rhino plus Rhinogold for just one project
> so I am still thinking about a way managing it within MOI.

Probably the MoI method would be to manually place them using Transform > Orient.

- Michael

As noted some months ago:
The Oct.10, 2019 V4Beta Wiki, under resources, shows new scripting properties for Face objects, including face.evaluateNormal( uv ).

Also Jan. 22, 2020 V4Beta Wiki, has scripting properties: face.dropPoint( pt ), brep.dropPoint( pt ), and Updated face.planarFrame().

But at the moment I have too many projects :-)

- Brian

Flow hex center points to frogback.

Process one flowed point.
Face.dropPoint(pt) to get uv.
face.evaluateNormal(uv).
Figure out actual point on the frogback surface, using brep.dropPoint( pt )?
copy gem, using its normal or cplane or something, to align with frogpoint and its normal.
Repeat

The Pave circles (gems) appears to be closely connected to Rhino, Grasshopper, and physics engine Kangaroo2.
Kangaroo2 is written by Daniel Piker, who is responsible for numerous grasshopper circle packings with center repulsive force,
and boundary avoidance... Rhino 7 comes with all three programs. (I have not purchased Rhino.)

- Brian

Hi Michael, I agree, "Orient" will be the main tool when doing it the manually !

Thank you very much Brian.

The Rhino video is nice, I agree - amazing programming work behind the tool.

It is a nice challenge to work out a method without the automated comfort
of a specialized pave tool, will have a look which way works best !

<< ... Kangaroo>>

Being MOI´s greatest fan, I try to avoid to move into Rhino as I
prefer the minimalistic Zenlike aproach of MOI.

If I had dozens of projects in need of an automated pave tool I would
consider Rhino but so far I am confident to find a way within MOIs
capabilty ...

Hi Tom,
not sure if this may help but in Blender there is an addon called Tissue that converts surfaces to hexagon mesh.
I've been using Moi to model and sending them to Blender via BMOI_Connector mentioned on this forum.
Anyway I have tried using an ico sphere created in Blender converting it to hexagon mesh and instance the gem stone onto the faces as shown in the photo.
On the left Sphere without smoothing, right with smoothing.
You can then bring them back into Moi via BMOI_Connector bridge.
Hope this helps.
Barry
Ps:this video may help
https://youtu.be/asBwqJKkFb4