Offset curve issue

I’ve met a problem trying to offset a simple curve. The result is “slightly” wrong:

Though the curve has more than 4 control points I still can’t understand what is the problem to offset it:

Tried to simplify it before offsetting, but it failed. The actual deviation from a line is 2.7e-5, but setting tolerance for Simplify curve to 0.1 didn’t help…

Has anyone some ideas how to make it work?
Thanks in advance!

Inspected the curve more thoroughly and found out that it has 27 control points (and not 16 as I used to suppose).
This curve was generated by Region Union from a number of cross sections of a mesh:

Dude, nobody can do anything with just your screen shots. It’s highly inconsiderate to assume so and to require this personal admonition to post your GH/geometry!!!

3. Attach minimal versions of all the relevant files


Very sorry!
I’ve just read the post 2 minutes before and have already prepared the grasshopper file.
Here it is:
Low level 2 meshes problem (42.2 KB)

Too late for me, I don’t enjoy being provoked this way, every day, over and over. SO RUDE!

Low level 2 meshes problem (43.4 KB)

It’s my first post here, so please be a liitle indulgent.
In any case I understand you. Hope you won’t ignore all my future posts.

Yeah, we hear that all the time. That’s what everyone says. New here, didn’t bother to read the forum before posting to it, or worse, argue that it isn’t necessary.

Finding the ignore feature on this forum has been a great relief and I’m not hesitant to use it.

Thanks a lot!
It works!

No one addressed you. Sigh.

Nope. Only once in a lifetime. Per new user that is. No one is targeting you. No one is after you Joseph. Promise.

You got it backwards.

// Rolf


Shame on me.

On a new data set I’ve met the similar problem. But now it is not caused by control points…
And unlike before offset works fine in Rhino, but fails in Grass.

Нижний слой (28.4 KB)

One more strange thing is that two meshes at the start of the script are the same, but the result is different.

Very common situation here. Use Clipper for offseting.

Thanks, that works, but I need round fillet and it makes lots of points even if I set tolerance to 0.1:

Compare to offset curve:

Is there any way to keep minimum control points (as with Offset Curve) and get robustness as with Polyline Offset?