Voronoi with cluster center points (known function for more realism)
I was comparing the Voronoi fracturing between Tyflow and "FractureFX" (an old Maya tool I have, which has several advanced features for fracturing).
There is it possible to set random so-called "cluster points" (either randomly by number or by tex map), which makes it much more realistic looking.

This is procedurally imitating a natural behaviour:
Glas is not breaking uniform, there are centers like spiderwebs, which are building the voronoi fractures.
It is possible to set the number of those clusters and drive their position for example with texture map.

Please have a look, this would let fractures look more like in real life.

I have attached a screenshot here.
Interesting you say that...when I originally wrote the Voronoi operator I had that exact functionality in there, but I eventually took it out for a reason I can't remember. Maybe I should put it back in...

Anyways, for now you can recreate that effect by simply setting the operator to use a separate particle system as the point source, and then generating some particles with localized child particles like in your screenshot. I've attached an example showing how.

Attached Files
.max   voronoiClustering.max (Size: 700 KB / Downloads: 7)
Thanks for your file, this is very helpful ! 
I drove the texture then with a noise map, which gives very fast different results.
=> I would like to share your file with this noise in the FB forum, because I'm very sure many people could use this.

Fracturing is one of the core tasks of visual effects (if you just look at the topics from Jessie or Allan McKay, it's a lot just about fracturing)

So I really would recommend to implement something similar to this into the Voronoi  - I'm sure it would immediately be integrated in their tutorials.
Because everything what is packed inside a single node and can be done just with a few clicks there, makes tyFlow (even more) intuitive :-)

Especially those beginners/intermediate users like me would be very greatful, because "we" quickly struggle with keeping track in too complex scenes and in cascaded flows.
An implementation makes it easy to use it as well with secondary and tertiary fracturings without blowing up the node tree.

2.)  I also tested PhysX contact (which sounds promising), but did not understand, how to add there an object
(attached screenshots) Could you explain, why it's not letting me to add the sphere?

3.) Of course you know, but I wanted to mention that Voronoi tweaking is also in Rayfire a wide topic: https://wck.me/1408
which just proofs, that there's huge demand and that for sure a lot of people would appreciate some more voronoi tweaking functions (even if it does not need every feature of the world)
Attached screenshots from there, but it's maybe worth to have a look yourself Smile

Many thanks!


.max   voronoiClustering per PhysX Contact.max (Size: 868 KB / Downloads: 5)

.zip   RF examples.zip (Size: 355.1 KB / Downloads: 7)
and also a houdini comparison... Smile

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