We also implemented the TriMesh node, and established a strong
convention for updating nodes from sockets via. socket superclass
method. `trigger_updates`. It should be triggered as the
`update=` callback on **ALL PROPERTIES IN ALL SOCKETS**. This
method in turn calls the nodal `update()` function, which in turn
causes the node to chain-update all nodes linked to any output socket.
By default, `update()` is `pass`, so performance shouldn't be a concern,
but we should think about this deeper at some point.
Because update-chaining is done, we're ready for preview toggles on
node outputs. A lot of exciting things to do now!
We're starting to have a very advanced socket-based language
for defining nodes. It's very practical already.
The priorities are
1. All the nodes!
2. Sockets, including default values, as needed.
3. Library constants, mediums.
4. Output socket previews w/geonodes, geonodes structures.
5. Utilities including arrays (and selected array multi-input)
The code is still very spaghetti. This is very much still the
"first, make it run" part of the system design.