Blender Git Loki

Crappy draft of basic traversal mechanism

Draft skeleton for sorting nodes...

Bugfix: Complete partially completed def (for bone parenting)

Skeleton for handling Rigidbody Sims

Blurb explaining design decisions for how rig graphs are constructed

Compositing nodetree graph building - just plain wrapper for now

Stub functions for building subgraphs from groups

Stubbed in animdata-adding for "Armature" data

There are still many todo's to be fixed up here for nice instancing,
but those require some other changes (aka proper proxies first). In the
meantime, we just want to be able to port this all up...

Comments - noted some issues re IK-Solvers steps which need to be solved still

Spline IK - Also add links back to root of chain (as for IK)

IK Solver - Keep a reference back to the root node of the tree in the solver

Ported rest of constraint stack graph building code

Temporary hack for name used when adding constraint stack op

This is because, this name currently serves double-duty when we're faced
with subdata nodes... This needs urgent fixing!

Attempted to port motion-tracker constraints to new system

* Most of this seems to port over ok
* Still not sure what exactly the "scene relation" at the end is for
* Because we've got a more descriptive system now, there's probably a lot
more that we can describe here now that wasn't possible before. However,
since I'm not familiar with this, I'll leave it as-is for now.

Added note about how constraints are represented + create constraints "stack eval" node

Spline IK eval graph building

Include link from IK-solver owner to IK Solver

Code for linking IK solver eval step to affected bones

* Added a new operation node "type tag" for evaluation processes
which take the "final" transform results and perform some "final final"
modifications which can only be done when looking at more than one
item at a time. Examples of this include IK Solvers and Rigidbody Sim Steps

Copying over logic for IK constraint parent-chain walking from depsgraph.c

Stub functions for handling IK-Solver Eval Nodes