Here’s one of those posts were we do something clever with only the built in tools in Fusion.  This time it’s getting the worldspace position of any node (or offset point from a node) despite downstream transformations.  Why do I need to make a special setup for this?  Oddly, Fusion doesn’t provide an easy means to convert between local and world coordinates, and someone asked for a way to do this on the Fusion-L listserv.

(Particle Emitter “attached” to a Sphere)

The biggest problem in Fusion is how it handles modifiers.  In the case of the modifiers for UI exposed parameters like points, or floats, or strings, you get a way to add modifiers, but not a really clean way of managing them.  But for 3D parameters, you get no modifiers at all, only an abstraction to float parameters, so a transform matrix is only available to the user as a list of floats for the PRS and pivot.  Sure, you can make your own “controller” with the 3D SDK, but a 3D tool that might affect a 3Sh won’t affect a pEm.