Line Perpendicular to a Surface

I have a point object on a nonplanar surface.

Is there a simple way to create a line perpendicular to the surface at that point?

Hi Jim - Line > Normal


Hi Pascal!

I am trying to draw a line, perpendicular to a given surface (in blue in my image), but starting from a point.

I tried to find it out but I am stuck! I am sure I am missing a very basic command, that seems to be such an easy task.

Thank you very much in advance!


in this case you should use ClosestPt command , select your surface then your point , rhino will create a point on your surface, just draw line between them and you will get your perpendicular.

Edit : this for Windows, hope you have this command on Mac.

1 Like

You can also just start Line>Normal, select your surface, when it asks for “start point” pick your point in space - the command will automatically place the start point of the line at the closest point on the surface - then click the same point again and you will get your line.

Note that neither of these methods guarantee that the line will be normal to the surface - the point will go to the nearest edge if it’s nearer than the closest perpendicular or if a perpendicular through the picked point can’t be found.



Yes, i missed this, thanks Mitch.

you can also “abuse” bounce for this. select the surface call bounce, choose your point from, then activate snaps on surface select the surface and click on the starting point, the line will be automatically normal from the surface starting exactly with your point.

1 Like

Hello Cyver,

Thank you very much for your knowledge!!! You solved my problem!!