TopoBuild SOP contains ‘Rewire Primitives’ operation type. How it works?

vux
TopoBuild SOP contains ‘Rewire Primitives’ operation type. How it works?

It is an internal operation used in situations where points should be fused/removed when manually editing points. To see it used, grab a boundary point and drag it over to another boundary point until it snaps then inspect the TopoBuild SOP's parameters.

Thanx. I know it, but how it exactly works. What Primitive indicies mean? I really want to use this SOP for my tools, because it can store many operations in one SOP. It can help in my scripts to avoid many SOPs (like many PolySplit nodes for example).

At now I can:
1. Delete prims,points,edges
2. Dissolve edges
3. Add points, primitives
4. Split edges. With some tricks

And I really want to know what it is for.


PS Any news about other operations that will be added soon - split etc?

PPS Guys thank you a lot for the most interactive SOP in houdini

vux
I really want to use this SOP for my tools, because it can store many operations in one SOP. It can help in my scripts to avoid many SOPs (like many PolySplit nodes for example).

The TopoBuild SOP is really only intended for interactive use with the TopoBuild state and its future development will be driven by this state's needs. It does not provide options for customising the behaviour from what is expected for the manual topology reconstruction use case (eg. no options to customise the edge dissolve behaviour). A Python SOP or an HDA that iterates over a list of operations may be more appropriate for custom tools.

The raw data for the “Rewire Primitives” tool basically describes which points each primitive should reference. It is used by the TopoBuild state when it wants to perform an operation similar to the consolidate mode of the Fuse SOP.

Ok. How do you think, can I use it for non interactive geometry reconstruction?
As I can see it really can reproduce destructive (non procedural) operations like splitting, adding, deleting.
In my case interactive PySide tools can produce simple SOPs. But maybe I can pack this operations in one node in some cases. It still just an idea, but simple tests give me good results. I think it can be a bit faster for recooking multi operations than using many sops (PolySplit, Blast, Dissolve…) where geometry travels through the nodes. What do you think?. Thank You!

And of course I think TopoBuild SOP can be extended (in future) to work as not only retopo tools, but simply produce comulative destructive edits)

or an HDA that iterates over a list of operations may be more appropriate for custom tools

Yes. It is good idea to calculate sops inside HDA with multiparms. Some of my assets works like this. But in my polygon toolset I still want to minimize using of custom HDAs

Think aloud…

We have Edit SOP. Comulative SOP that can store all transformations that don't change topology.

For example: In custom interactive tool we can calculate result with Python, VEX, nodes. After that result can be saved to previous Edit SOP. In this case all transformations (moving, smoothing, rotating, sculpting, aligning etc) works with just ONE SOP.

It would be good to have another comulative SOP that change topology: split, fuse, collapse, deleting, adding. In this case we have two very useful SOPs.

Making human model, for example, will produce only 2 types of nodes and the tree (if user need it) will have very few nodes…

…

Or maybe improving Edit SOP for have topology-changed operations. This will produce just one node