Meshes join problem

Hi all,
Dont know whats going on here exactly but i cant join this two meshes. The idea is later export as one single mesh into ecotect. In the definition i used giulios piacentinos definition for variable diagrid. ( the model i am using is just an exampletoroid)

Evertytime i try to join them, the mesh that completes the big one dissapears!

Attached the files in gh 07 and r4

Cheers!!

Attachments:

Replies to This Discussion

Permalink Reply by Giulio Piacentino on September 26, 2010 at 5:57am

Hi Javier,

an important property of meshes is the orientation of the face, also sometimes simply referred to as "direction of normals". Faces have direction implied by the right-hand rule, therefore points need to be specified counterclockwise seen from outside, or frontally for open meshes.

So, your definition was almost right - I just modified the order of the points in the Surface from Points component and it started showing the mesh (please notice that the mesh was already there and that Grasshopper's own "Join Meshes", recently introduced, also unifies the mesh normals, but does not weld vertices).
I hope this is helpful,

- Giulio
________________
giulio@mcneel.com
McNeel Europe, Barcelona

PS: one could also modify the script to add the remaining case of a surface that is closed or periodic in both U and V directions (it's the last remaining case in single-surface NURBS topology).

Attachments:

mesh-normals.ghx, 557 KB

Permalink Reply by Javier Ruiz on September 26, 2010 at 7:16am

Hi Giulio, thanks so much for your reply,

In your def there are still 2 faces with nornal inwards. In a list of 20 i think these are items 0 and 19, the first and the last one. How can i fix this? Not sure if its better changing normals faces of the surface or the meshes. The problem is that is not the hole list, just 2 items, and once ive changed these 2 items normal i cant insert them in the correct position again! not sure why but insert item just allow me to insert after the indexes of a list not inbetween or before. Sure im doing something wrong..

Cheers!

Permalink Reply by Giulio Piacentino on September 26, 2010 at 8:19am

Ops, that's true - I missed those two. I've recomposed the last part and now it directly makes a mesh. Without surface joining, where the problem was coming from.
Like this it should be faster as well.

- Giulio
________________
giulio@mcneel.com
McNeel Europe, Barcelona

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