Move surface changes it's orientation

Maybe I’m missing something ridiculous here. But I’m just moving this surface around in the attached 3dm file and it seems that by moving it, the orientation of the surface changes (very slightly) - it’s no longer perfectly alligned with the viewport planes.

I’ve tried moving the surface with the Move command and moving by dragging the Gumball.

I’m confused by what’s going on here

sketch.3dm (30.8 KB)

from here looks ok. maybe is because you are working very far from origin.

If you increase the display precision, to 1.00000 say, open the Boxedit panel and select the surface you will see that it is actually not quite aligned to the world planes in the first place. When you move it around this far from the origin that variance increases (presumably because of rounding).

If you use SetPt to flatten the x-direction and then retry the move you can find that the orientation remains parallel.

Regards
Jeremy

That explains, I only wonder why it’s not alligned in the first place. I just drawn the surface as a rectangular plane. So I assumed it should always be perfectly straight. Maybe also because I’m so far from origin?

(I copy/pasted this sketch from a much bigger drawing, that is the reason origin is so far away)

Yes probably. Also, I will hazard a guess that you drew the plane with the mouse rather than by entering co-ordinates as your positions and dimensions are not rounded to realistic accuracy for the size of object. You can draw more accurately by entering values via the command line (see https://docs.mcneel.com/rhino/6/help/en-us/index.htm#user_interface/accurate_modeling.htm#Coordinate_entry
). And SetPt is a great tool for nudging things into alignment with the construction planes.

2 Likes

Good to know,

you are right, i drew the rectangle with my mouse,

regards,
Simon