SURFACE TERRAIN FRON CONTOUR LINES HELP

Hi, I have contour lines from an autocad and im trying to reconstruct the surface, the problem is the contour lines are in segments and i tried using delaunay and its not giving me a surface as a I need it.

Im uploading the rhino and the grasshopper

i d appreciate any help!

thanks,

melanie undefined TERRAIN.gh

Replies to This Discussion

Permalink Reply by peter fotiadis on May 8, 2016 at 10:57am

Anyway with a good dose of Karma maybe (just maybe) it's doable (on the limit - note:DO NOT use the option "rebuild").

Shown 1/3 of your data (don't ask about deviation - pointless on that scale).

Don't forget to get rid of the big triangles at the perimeter ("trim" the mesh, that is).

Permalink Reply by melaniesrud on May 9, 2016 at 1:31am

wow thats looks pretty good, can i do it by halfs right? but for some reason the definition u gave me gave me error when i tried to run it

Permalink Reply by peter fotiadis on May 9, 2016 at 2:12am

Error(s)?? what error(s)?

BTW: For THAT amount of data ... avoid using WB Loop (reset MeshMachine if you change the Length input [average gives you an indication about the "proper" value])

Other than that: how to create (manually) a "trimming" mesh (closed polyline > extrude > mesh) and get rid or the bad things that happen in the boundary.

Permalink Reply by melaniesrud on May 9, 2016 at 2:16am

i just realice the errors are because i dont have the right plug ins installed, im trying to solve it, im sorry im kind of new in grasshopper.

I cant seem to find wavebird component

thanks a lot

Permalink Reply by peter fotiadis on May 9, 2016 at 2:28am

WB is a plug in that does mesh things.

Component used is part of the "package". Install WB to get rid of the errors (but as I said: you don't need it for this case > use rather the MeshMachine or process the mesh using some pro level subdivision modelling app [ Modo is the best by a million miles]).

In fact Modo can do what you want with a vast variety of ways. If you do frequently business with meshes > this IS the ultimate (straight out from the US Movie Industry). Modo has the best rendering engine by a million miles as well and provides the best approach for key framed animations (that one is utterly brilliant).

Permalink Reply by peter fotiadis on May 9, 2016 at 10:24am

Re start from node 0 (in case that someone else is also interested).

BTW: File size limit in this Forum is 5MB (but ... your data are 20MB).

This (a bit freaky "around" the boundary):

means that you have selected some polylines > you got the points > and then you have used the first of the 4 options: The Patch (that yields a nurbs), that is.

Explanations about why the outer Loop edges do that (and what the hell a nurbs surface is anyway) are a bit complex and rather off-topic this very moment ... but let's say that this is the way that Patch works - given the data provided, that is.

Note: DO NOT attempt to create "segmented" nurbs (due to the huge amount of data) and then try to "stitch" them together (i.e. Join Brep). This is expert only territory not to mention that requires a huge amount of good Karma.

If on the other hand you want to "tame" the boundary use the 3 remaining options [yielding meshes] AND the simple way described already to "trim" (i.e. split) the mesh in order to get rid of the Delauney "big" mesh faces that occur "around" the boundary.

But ... you can do that as well using ONE nurbs (if Patch can handle that amount of data) meaning that you MUST sample all the polylines > points > to Patch component.

WARNING: Bring your data "around" the global origin (say the "center" of the sum of polylines at Plane.WorldXY.Origin) > they are far far and away causing a variety of issues related with tolerance and other mysterious things.

Plan Emergency Rescue Because It's A Matter of Life or Deoth: Skype.

Permalink Reply by peter fotiadis on May 9, 2016 at 11:25am

BTW: Some hints more:

1. Make the suitable "cutter" BEFORE anything else (polyline > extrude > mesh).

2. REDUCE some stuff: for instance

3. Run the delauney mesh

4. Then either split the mesh BEFORE MeshMachine (rather better) or after

BTW: For a mesh with 7M points ... well... you'll need some proper CPU to deal in a reasonable amount of time (what about a Xeon E5 1630 V3?).

Alternatively find a friend who knows very well Modo ... and see first hand what the US Movie Industry is all about.

Permalink Reply by ng5 Alex on May 9, 2016 at 10:48am

Hello melanie,

Since your initial post is with meshes, your first attempt is ok, but you need to flatten your points before inputting them to delaunay mesh component. You can also divide the curves according to their length, so that you don't have too many points in small length-ed contours.

You can also do the following, in this case discontinuity component is used.

this works with many many curves and points quite quickly.

best

alex

Permalink Reply by melaniesrud on May 9, 2016 at 1:51pm

thanks i manage to solve it finally, now another doubt maybe u can help me: when i bake the mesh is extremely heavy, theres a way to light it up? thanks for all the help!

Permalink Reply by peter fotiadis on May 9, 2016 at 11:40pm

This:

http://meshlab.sourceforge.net/

Is open source and although full of bugs (we are talking a lot, he he) ... it's your best ally for similar mesh puzzles.

Not something that you can master in 5 minutes, mind

Permalink Reply by peter fotiadis on May 9, 2016 at 11:58pm

If MeshLab is a bit heavy for you ... here's a very primitive way to reduce a mesh

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