Let Rhino believes a geometry is moving but not practically moving it

Rhino Developer
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1

Hey,

I’ve been trying to let Rhino believes that a geometry is moving, but I don’t want to really move it. The purpose is just sending a signal, so the “geometry modified” event can be triggered, or periodic curve won’t break when I edit grips.

My simplest approach is nudge it as small as it can, so it is:

Transform zeroXform = Transform.Translation(new Vector3d(double.Epsilon, 0, 0));

Short answer is - it works every time. But when I ask opinions from LLMs, they all tell me this is dangerous for many reasons (they are bitwise identical, semantic misleading, unstable across APIs, etc).

So, I wonder if this is really the case? Should I avoid doing this?

Looking forward to any insights!

2

You might try Transform.Identity.

– Dale

3

Hi Dale,

Thank you for the quick reply!

After testing, I found Transform.Identity won’t trigger RhinoDoc.AddRhinoObject as the way that a real nudge does, unfortunately.

But it did inspire me on the periodic curve case. A straightforward copy of the Point3d works. So, I guess it only monitors if it is still the same struct, it is not based on real location.

4

Why not move it and then move it back?

5

Because this will trigger the event twice.

6

true. What about a 360 degree rotation? Also bitwise identical?

7

Yeah - just gave it a quick test, the same.

I think I am gonna stay with my Epsilon trick, since no side effect is shown for now. :slightly_smiling_face: