Trimmed and Untrimmed Surfaces!

Hello

I have 2 planer simple surfaces (one rectangle and one hollow circle for explanation purposes). I made the hollow circle by doing the following steps:

create a circular surface (the original circle).
Offset the original surface by 2 m using the "Offset" tool.
Perform a "solid difference" action to separate the outer ring from the original circle.
Disable the "Preview" of the original circle, thus showing only the outer ring; which is the shape that I want.

I want to union the two surfaces. The problem is hat the hollow circle is now a "trimmed surface" and can't be unioned with any other "untrimmed surface" such as the rectangle. The "union" always results in 2 locally defined values instead of 1. I want to union them and get one locally defined value (just one surface as an output with one area and one center). Does anyone know how to do it? I tried the "untrim" tool and it didn't work also.

Attachments:

Trimmed Surface Union.gh, 11 KB

Replies to This Discussion

Permalink Reply by David Rutten on January 14, 2015 at 6:27am

Solid Union isn't about trimmed or untrimmed, it's about closed and open. Solid Booleans were designed to work on closed objects, though they usually work on open ones as well.

The problem here isn't to do with the nature of your shapes, it's because the shapes are in different branches of a datatree:

One surface is stored under {0}, the other under {0;0}. You need to put them both into the same list to make the Solid Union operation treat them at the same time (solution attached).

Attachments:

TrimmedSurfaceUnion.gh, 4 KB

Permalink Reply by Ibrahim Abotaleb on January 14, 2015 at 6:47am

Thank you David! your solution is perfect :)

Permalink Reply by ng5 Alex on January 14, 2015 at 6:46am

Hello

in case you don't want the initial surfaces edges in the final unioned surface you can do the following.

cheers

alex

Permalink Reply by David Rutten on January 14, 2015 at 8:44am

There's also a Merge Faces component which combines adjacent co-planar faces in a brep.

Permalink Reply by ng5 Alex on January 14, 2015 at 8:49am

Ah yes. one component solution!.

Permalink Reply by ng5 Alex on January 14, 2015 at 9:05am

this has happened to me and other times, creating parts of definitions and then realizing there is a component already doing them. its kind of doh moment and thought of opening a group posting cases like this for fun.

RSS