# Kangaroo 2: Using Circle as Achor Point / Openings

**URL:** <https://discourse.mcneel.com/t/kangaroo-2-using-circle-as-achor-point-openings/127741>\
**Category:** Grasshopper\
**Tags:** windows, kangaroo-2\
**Created:** [July 21, 2021, 9:26am UTC](https://discourse.mcneel.com/t/kangaroo-2-using-circle-as-achor-point-openings/127741 "2021-07-21T09:26:35Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![hbrooks](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/hbrooks/32/306554_2.png) [@hbrooks](https://discourse.mcneel.com/u/hbrooks)\
**Post date:** [July 21, 2021, 9:26am UTC](https://discourse.mcneel.com/t/kangaroo-2-using-circle-as-achor-point-openings/127741/1 "2021-07-21T09:26:35Z")

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Hi All,

I have been enjoying playing around with Kangaroo 2 and have familiarised myself with it.

I was looking to do something a little more in-depth. Please see attached example. I was looking to generate a mesh using Kangaroo in a similar fashion which uses the circles at the bottom of the columns as the bottom anchor and the ceiling as the top anchor. I have seen examples that uses 2 curves to create the surface but not 3 (two anchors at the bottom and 1 top constraint).

I can’t seem to find an example of this and was wondering if anyone knows of a script to troubleshoot this? Please let me know if you need any more information/description to help troubleshoot.

Thanks,

Harrison.

 ![Kangaroo Example](https://global.discourse-cdn.com/mcneel/uploads/default/original/4X/b/6/7/b670a950ed10d4fcd98cf289b774fbfbda59d6da.png)

![Underneath_Day_web](https://global.discourse-cdn.com/mcneel/uploads/default/original/4X/2/e/2/2e21b1a71d893d64c80310c8d9af7a98b4baa4b1.jpeg)

[Kangaroo Column Scipt.gh](https://discourse.mcneel.com/uploads/short-url/oc3OcTfz9PI9r5pPo3N2AYuWsqg.gh) (4.9 KB)

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**Author:** ![johnharding](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/johnharding/32/490155_2.png) [@johnharding](https://discourse.mcneel.com/u/johnharding)\
**Post date:** [July 22, 2021, 1:52pm UTC](https://discourse.mcneel.com/t/kangaroo-2-using-circle-as-achor-point-openings/127741/2 "2021-07-22T13:52:49Z")

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The easiest way is to construct a mesh that represents your surface (topologically) on the plane, then move vertices and fix them before relaxation. In your case, I would make a planar surface with the top curve, trim this with the two circles (raised 5600mm), convert to a mesh, and then finally move the vertices around the circle cuts back down 5600mm. Then just run Kangaroo on this mesh, fixing the naked vertices, and adding forces or tweaking the mesh edge strengths as you wish to get to a desired shape. You can also use the checkerboard utility Daniel created to pick out a pattern of faces similar to the image and colour them differently perhaps.

Of course how you construct the initial mesh in a more refined way has a bearing on the final shape too, but that’s another level of detail that maybe you don’t need.

 ![anotherSurface](https://global.discourse-cdn.com/mcneel/uploads/default/original/4X/1/4/9/14916eaa42ab42fbd46fc27be270d2fdde01eedc.jpeg)

[quickgrass.gh](https://discourse.mcneel.com/uploads/short-url/yE1NCPccvo3kJJuuj4YwzrZc0IE.gh) (8.3 KB)

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**Author:** ![hbrooks](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/hbrooks/32/306554_2.png) [@hbrooks](https://discourse.mcneel.com/u/hbrooks)\
**Post date:** [July 27, 2021, 2:39am UTC](https://discourse.mcneel.com/t/kangaroo-2-using-circle-as-achor-point-openings/127741/3 "2021-07-27T02:39:49Z")

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Hi @johnharding

Thanks for your reply. I have done as you suggested and it is a great help thank you!

I was wondering how you achieve a more even distribution of vertices in the mesh especially for the ones that have been stretched down 5600mm? Like the ones in the image shown. Currently, I am getting something like this which is less than ideal.

Thanks,

Harrison.

 ![image](https://global.discourse-cdn.com/mcneel/uploads/default/original/4X/5/3/b/53b247ff7f7fbc78dbab19b0d7addd425a84c8b6.png)

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**Author:** ![johnharding](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/johnharding/32/490155_2.png) [@johnharding](https://discourse.mcneel.com/u/johnharding)\
**Post date:** [July 28, 2021, 3:27pm UTC](https://discourse.mcneel.com/t/kangaroo-2-using-circle-as-achor-point-openings/127741/4 "2021-07-28T15:27:49Z")

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> [@Introducing TriRemesh - high quality triangular and hexagonal remeshing and shrink wrapping](https://discourse.mcneel.com/t/introducing-triremesh-high-quality-triangular-and-hexagonal-remeshing-and-shrink-wrapping/115434):
>
> Happy New Year everyone! Wishing all of you and your families a healthy and joyful 2021 I’m pleased to share a new tool for fast and robust generation of high quality isotropic triangular meshes (and their duals) from a Brep or mesh input. The resulting meshes consist of triangles with similar edge lengths, angles and areas. This will be included in Grasshopper in the next Rhino 7 service release candidate. The n…

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**Author:** ![kotto\_97](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/kotto_97/32/604068_2.png) [@kotto\_97](https://discourse.mcneel.com/u/kotto_97)\
**Post date:** [July 28, 2021, 10:50pm UTC](https://discourse.mcneel.com/t/kangaroo-2-using-circle-as-achor-point-openings/127741/6 "2021-07-28T22:50:41Z")

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[![](https://global.discourse-cdn.com/mcneel/uploads/default/original/4X/9/8/8/988af1b19fe835d868e9499c8c75705ca2338691.jpeg "NEW MILAN TRADE FAIR REVISITADO [ESFGH] - ARCHICAD + GRASSHOPPER3D [PT/BR]") ](https://www.youtube.com/watch?v=Te-RN3nk3iw)