I'm not too sure I understand how the abstract control works with blendshapes, as we're not actively connecting its output to drive shapes. All I can see is an input.
it feels like the output is fed back to the parms attribute but without any physical connection. when I would expect something like this instead:
In apex works a little differently to what you would think. When you enter the viewer state, a scene graph is created in the viewport to drive the paramters on the rig graph. Think of it as a simplified rig to set values. So the Transform Object and the Abstract control that you are using in the viewport is not actually the one in the rig. This is why the control needs to be promoted to be visible, because if its not promoted it doesnt get created in the scene graph. This is also why it feels like things work in reverse.
All controls in the graph, so the TransformObject and the AbstractControl update the input parm values on your rig. so any other node that is connected to the same input parm port as the abstract control will also be set.
It helps a little bit. That was sort of my deduction (not to that extent though) So if I understand what you're saying correctly, when you enter the viewer state, it almost like the rig parms generate inputs ports and my controls get plugged into those inputs to feed my rig?
One thing though is when I tried to use a TransformObject to drive my shapes instead of AbstractControl, this didn't work anymore, I actually had to connect the TransformObject value in my set_shapes node.
