Pick surface/curves/polylines by number of edges

I am using Lunch Box Hexa grid, and sometimes it will divide the edge hexagons into half hexagones ( aka they will have 4 edges instead of 6 ), Is there a way I can cull those out of a list ?

Replies to This Discussion

Permalink Reply by Armin Seltz on November 9, 2015 at 6:22am

Sure. What you do is you break the grid into lines using "Deconstruct Brep", then counting how many edges there are.

Then you can use "larger than" and input 4, so you get a true value for all that have more than 4 edges.

Then you use Dispatch to split the original list of hexagons using the true and false values of the largen than component.

This is a very common pattern in GH that you will use a lot. Checking something and using the results of the check to differentiate something else.

If you have a .gh file you can upload it here and I will show you how to do it with your specific example.

Permalink Reply by Mohanned Iskanderani on November 9, 2015 at 11:36pm

I freakin love you man. It worked. Thanks so much !

Permalink Reply by Armin Seltz on November 10, 2015 at 1:11am

I'm glad I could help. Happy Grasshopping!

Permalink Reply by Frank T on January 4, 2017 at 8:57am

Hi Armin,

it sounds simple but I can't get this to work. Can you send the definition?

Would be great!

Frank T

Permalink Reply by Frank T on January 4, 2017 at 9:01am

It's maybe because I'm dealing with non planar hexagones created by paneling tools.

Permalink Reply by Armin Seltz on January 4, 2017 at 9:19am

Hi Frank,

well, the answer was more to do with how you can seperate something into 2 distinct lists, then do different operations on each. All you need for that is basically the Dispatch component and something you are checking, which gives you a true/false value.

I am not sure of your specific problem. You should post your .gh file, then its much easier to see what's going on. Maybe its due to data tree structure that things are slightly different.

Permalink Reply by Frank T on January 4, 2017 at 9:39am

Thanks! I'm trying to filter out the poly lines with 4 edges on the sides.

How to go about doing this? The poly lines are not planar.

Help would be great! Frank T

Attachments:

Hexagone-Paneling-Forum-1.gh, 4 KB
Forum-1.3dm, 87 KB

Permalink Reply by Frank T on January 4, 2017 at 9:42am

I can't manage to isolate the value that indicates the number of edges...

Permalink Reply by Armin Seltz on January 5, 2017 at 2:13am

Okay, I had to try a few things before I got it to work. Number of curves per cell didn't work, area didn't work and length also didn't work. But finally the number of vertices (points) in each cell is distinct enough in the incomplete hexagons.

So just explode the curves, count vertices and then use dispatch to split into 2 lists.

Attachments: