I have a particular use case where this would be useful.
When you create a CSYS using another CSYS as the origin point, the orientation tab has a "Set Z Normal To Screen" button. Essentially, what I'm looking for is a feature like that, but that will update to the current screen orientation after regeneration, without having to go back and click that button again.
I think there is a path using analysis features. You could analyze the angle between the "top" and "front" planes for instance (90°), and select the button to "Project the measurement into your computer screen plane", to create a "Projected Angle" parameter. This does update with each regeneration! But... it's a strange duck of a measurement; will require some fancy math to convert to CSYS orientation angles. And, it creates an error if you are at an orthogonal orientation. So to create something robust that updates the orientation of a plane no matter how the view is oriented, you'd need a few different sets of these measurements, some if statements in the relations for error handling, and lots of math...
Anyone figured out more specifics? I imagine I'm not the first person that has such a need...
