Normal to surface

Replies to This Discussion

Permalink Reply by Michael Pryor on June 6, 2017 at 3:42pm

Use the evaluate surface component, it will give you the normal of a surface at a point. 

Permalink Reply by David Boynton on June 7, 2017 at 8:25am

Hi Michael

 Thank you very much for your help / advise

regards

Dave

Permalink Reply by Petras Vestartas on June 7, 2017 at 9:02am

What kind of curve do you have?

If it is  a line then it works.

But if it is a curve then you have multiple directions along the curve on a surface. 

Then it will be probably some approximated curve, when its control points are moved  according to multiple normals. 

Permalink Reply by David Boynton on June 7, 2017 at 9:24am

Hi Petras

yes it is a curve.

The curve  was first mapped from a flat surface to a 3d surface then I wanted to offset this mapped cure normal to the 3D surface then I can use these to build a new surface.

Or I want to use the Mapped 3D curve to cut the surface then offset the cut surface normal to the surface it was cut from.

All for building a shoe

Thank you for your help and advise

regards

David 

Permalink Reply by Michael Pryor on June 7, 2017 at 9:32am

Can't you attach a file or image?

Permalink Reply by David Boynton on June 7, 2017 at 9:50am

Once I am able to map the 2D crv to the 3D object ( Last ) I can then use that crv to trim the 3D object and start to make parts.

At the moment the 2D crvs are not mapping correctly.

I took a 40 hour class in GH about 3 years ago so I am in the process of getting back into it.

Many thanks

DB

Attachments:

• Grasshopper - 2d-to3D-crvs_.png, 570 KB

Permalink Reply by Michael Pryor on June 7, 2017 at 10:03am

I don't understand how this relates to your original question?

"I am looking to extrude curves normal to a surface"

Is this a separate question now about mapping curves and cutting a surface?

Permalink Reply by David Boynton on June 7, 2017 at 1:19pm

I got a little carried away, Sorry.

I mapped a  curve to a 3d surface. I want to then offset this curve normal to the surface.

I used the eval surf but am confused on selecting the uv point

Permalink Reply by Michael Pryor on June 7, 2017 at 2:21pm

It should be something like Petras has said, you will need some sample points (in this case I used control points) then move those in the direction of each points normal on surface, remake the curves, then loft them to the original curves on the surface. 

Attachments:

• LoftCurveAtSurfaceNormal.gh, 10 KB

Permalink Reply by David Boynton on June 7, 2017 at 2:28pm

thank you very much for the help

Have a great day