Summation of 4 vectors

Replies to This Discussion

Permalink Reply by David Rutten on January 21, 2013 at 3:38am

Vectors don't start anywhere, they are merely directions and magnitudes. If you want to compute the average of a set of vectors, then you can use the [Average] component. If your vectors have different magnitudes, then the average will be weighted towards the longer ones, so if you don't want that, you'll need to unitize your vectors first. Adding four vectors together can be done using the [Addition] component (that'll be annoying though as it requires 3 of them). If your vectors are already in a single list, then you can use [Mass Addition] to add them all in one go.

--

David Rutten

david@mcneel.com

Poprad, Slovakia

Permalink Reply by David Stasiuk on January 21, 2013 at 3:54am

Is it important that you keep each panel a distinct mesh?  Because if you join and weld them, you will then be working with one mesh whose vertex normals will be unified and it's really simple to do it.  However, if you want to keep each panel as a mesh distinct from one another, you can use "closest points" to identify the index of the nearest points and collect the related normals for summation.

Attachments:

• mesh_normals.gh, 420 KB

Permalink Reply by Cristina Nan on January 21, 2013 at 4:37am

thank u for your reply. I have attached a simplified version of my file to show the exact problem i am having. the surface should remain as one unified mesh...

Attachments:

• simplified_example.gh, 6 KB
• 21012013_test.3dm, 129 KB

Permalink Reply by Cristina Nan on January 21, 2013 at 5:17am

i tried adifferent approach, but I still can't figure out how to generate the vector summation of 4 neighbouring panels. closest point won't work

Attachments:

• VectorSummation.gh, 8 KB

Permalink Reply by Cristina Nan on January 21, 2013 at 9:09am

Thank u!!

Finally managed to solve my problem with the help of your file!

Permalink Reply by Chris Tietjen on January 21, 2013 at 9:24am

It's not really the 'normal of a point'.  It's the resultant vector of the sum of the four normals of four adjacent surfaces placed at the common intersection of all four surfaces.  I guess it's true meaning depends on what you do with it next.

Attachments:

• 9_SumFourVectors.gh, 16 KB

Permalink Reply by Cristina Nan on January 21, 2013 at 10:11am

Thanks! your solution is similar to one I have found and works just as well for what I intend to further do with it. I intend to apply this on my real panalized surface in order to create a on offset of my surface thus using it to generate a specific frame structure.

Permalink Reply by Michael Pryor on January 21, 2013 at 10:26am

maybe Im misunderstanding because I am missing some plug in to open the files but this seems like a valid solution from what I read. Maybe not. Requires weaverbird.

Attachments:

• mesh.3dm, 53 KB
• mesh offset.gh, 4 KB

Permalink Reply by Michael Pryor on January 21, 2013 at 10:13am

whats the plug in ptcomponent?

Permalink Reply by David Stasiuk on January 21, 2013 at 11:07am

It's paneling tools...some really nice stuff in there

Permalink Reply by Michael Pryor on January 21, 2013 at 12:54pm

ah yea. "pt" makes sense :)