I found some threads concerning flipping or reverse normals. One is about flipping splines.
But I cannot follow how to reverse. Too - I´m not sure if it is the solution for my problem...

When I was multiplying and manipulating a gyroid "curved-triangle" patch, some had surface normal that was the reverse of what was desired. Select patch Surface, and invoke Moi command 'Flip'.

The concepts of "inside" and "outside" were lacking for the geometry ???

- Brian

(My patches were NOT quite perfectly smooth with each other.)

Do Splines have normals???

Edit:
Google search "Normal of spline"
StackOverflow has responses.

Post your 3dm file!

Else for Flip something press TAB and write Flip

While in the command, click the curve a second time

Hi Mala, generally the natural direction of a curve does not matter in Moi because of stuff like the end nearest to where you clicked on it when selecting it is used rather than the default direction.

So although there is a "Flip" command it won't really do anything.

Some commands like Loft will automatically figure out directions but also have an option where you can click on one of the curves while at the Loft options stage to reverse it.

It's difficult to know what's happening in your specific case without seeing the .3dm model file, please post it here or you can e-mail it to me at moi@moi3d.com if you want to keep it private.

Thanks, - Michael

Performing Flip on a curve reverses the Start and End points.

I am probably not understanding the question, and could use some education about the Normals of curves :-)
2D and 3D...

- Brian

ccc script shows either curvature line segments, or radius with line segments.
I know of Normal and Binormal... Maybe they could be added to ccc script, along with tangents and derivatives?

Brian,

“”” Performing Flip on a curve reverses the Start and End points.””””

You are well informed. The mis conception is that the command is using the start and end points of the curve.

The command is using the “point you click on the curve” as the info it needs. (Like the flow base and target selection.)

So the reversal is done within the command and clicking your input curve relative to its endpoints can reverse the “direction” of the input.

Sample: loft between 2 curves and while in the loft command, click either end of 1 of the curves.

Thank you very much Burr.

After a lot of Loft practice, and careful reading, I've finally understood.

- Brian



I will risk one statement regarding additional actions :-) If History was on for the Loft, then after Loft is Closed, A Flip of one of the two curves causes the lofted surface to switch to its other version. (And reverses start and end points of said curve.)
(Proximity selection of one curve in the middle of the Loft does not change the start and end points of said curve.)