sort Mesh

Hey,

do I have a chance to sort the MeshFaces (see first Picture)? Best solution would be like the second picture

Replies to This Discussion

Permalink Reply by David Rutten on March 23, 2011 at 1:29pm

When you window-select objects in Rhino, the order in which they are returned is by ascending runtime-serial-number. Whenever an object is added or changed in any way, it gets a new runtime serial number. So you cannot rely on a window-selection to give you what you want. Of course if you generate the points directly in Grasshopper, there is a logical order to them, even though it may not be the order you need.

If you want to import points in an ordered fashion from Rhino, you'll need to either select them in the right order, or sort them afterwards.

David Rutten

david@mcneel.com

Poprad, Slovakia

Permalink Reply by Danny Boyes on March 23, 2011 at 1:44pm

You need to set your guide line perpendicular to your rows of points then it will work as you want.

Attachments:

2dsort_LG.ghx, 1.5 MB

Permalink Reply by L]G on March 23, 2011 at 2:08pm

Thanks you very much for all the help guys. that is exactly what i needed :)

Permalink Reply by L]G on March 23, 2011 at 4:41pm

Hi again, sorry for being a bit anoying. although it was exactly what i needed, now i have given up trying to connect the point as it is imposible to create the line adequately, so i have then drawn them over the point as shown below.

i know how to go from surface to triangualtion, but i cant figure out how to go from the lines to exploded surfaces in between.

im really stuck with this and it is the source of my study, thanks

thanks

Permalink Reply by Danny Boyes on March 23, 2011 at 5:57pm

Is this any good? It uses the Compare component by @nzarchitecture from http://www.parametricmodel.com/Compareeveryiteminalist/38.html

It's a bit of a brute force method and doesn't make use of the 2D sorting algorithm discussed here. The basics are it creates a line between every point without duplication (Hence the Compare component) and then culls every line outside a set length domain.

Attachments:

CullComparedLines.ghx, 750 KB

Permalink Reply by L]G on March 23, 2011 at 6:41pm

Hi Danny, thanks for all ur help and time. i was really excited when i saw how the lines turned out to be, which is exactly what i was looking for, theni i exploded the end result and im back with the point :), i have done tons of 'culls' and 'items' to try and extract the point i need to create a 4 point surface for each diamond shape, but nothing seems to stick.

Permalink Reply by Danny Boyes on March 24, 2011 at 11:05am

Hi L]G,

I think I've cracked it.

The definition eventually creates 4pt Srfs after selecting adjacent pairs of triangles from a delauney mesh.

Attachments:

LG_Srfs.ghx, 1.1 MB

Permalink Reply by L]G on March 23, 2011 at 7:55am

hI, a fellow user redirected me to this thread, but i have not been able to apply the definitions to my problem,here is the post

http://www.grasshopper3d.com/profiles/blogs/sorting-points-based-on

Thank you so much in advance

Permalink Reply by Danny Boyes on March 23, 2011 at 8:37am

Yeah it was me that sent you here. I was refering to the post for

This file shows the basic idea of 2D sorting. If you don't understand why it requires an expression like:

from + (along * 1000)

let me know, I'll try to explain.

There is a ghx attached to that post which will sort primarily on the X direction (along) and then any identical X will be diferentiated by the Y (from).

Permalink Reply by Dedackelzucht on March 24, 2011 at 1:36am

Hey,

Thanks all of you for the nice informations.

I have got some more pictures for the pathmapper in my libary. I do not know who made the pictures, sorry for that. I think they are very helpfull to understand, what you can do with the pathmapper.

Permalink Reply by Danny Boyes on March 24, 2011 at 3:38am

The top image was posted by me when asking the question "Is there a more elegant way?" The answer came back that % instead of \ was all that was needed.

The next two were posted by me as an answer to a specific problem, they do the same job. Which is to append a point as the first branch by giving the two trees the same data structure and moving the existing tree along a branch.

The third was posted by Beltrán Fernández Mariño in answer to the question about grouping items on branches.

And the last was quite possibly the first real insight for everyone into the inner workings of the Pathmapper. It was posted by Sameer Kumar, and if you do a google image search on "pathmapper" that's the first image to come up.

Permalink Reply by Dedackelzucht on March 24, 2011 at 3:45am

Thank you Danny for your post. I have to save the names next time. Authors sould be always honored!

DeDackel