My plugin stores some coordinate information (like an origin). Ordinarily I can use GetPoint for this. However if the user wants to move the geometry in a document, there is no way for them to simultaneously alter the coordinate information in the plugin so it stays the same relative to the geometry.
One approach would be to monitor RhinoDoc.BeforeTransformObjects and update the coordinates whenever the user transforms something. But then there is no way to know if the user intended to only transform the objects, or the coordinates as well.
My preferred approach would be to show the coordinates as a virtual grip or handle only under certain circumstances which the user can ctrl+click to transform together with the other objects. So far I’ve found CustomObjectGrips, but that requires a specific RhinoObject to which to attach the grips, which doesn’t necessarily exist in my case, and it also requires a command, which I also don’t want to have. Essentially I want to have something like a DisplayConduit which is also selectable and transformable like a normal object. Is there any way to do this?