wing surfaces

Hello Folks-

I´m totally new to grasshopper, so please excuse if my questions sound stupid.

But I have been seeing so much cool stuff beeing done in grasshopper- I just have to try it my self :)

So my question is possibly an easy one-

I have some surfaces, in this case its kind of a wing-(see the picture) but it consists of more then 1 Surfaces- so in rhino would like to join them into a polysurf. and then make gh understand that polysurf as it would be one entity- to do more stuff like "divide surface" and later panelise it.

But I cant find a way to make gh use them as one surface and have the points evenly ditributed along all of them (as if there was just one)

is this possible at all? or am i missing something?

thanks james

Attachments:

wing.JPG, 111 KB

Replies to This Discussion

Permalink Reply by nikos tzar on January 24, 2015 at 2:52pm

Hello James,

To create a polysurface you can use [join brep]. Still, a polysurface (aka brep) is not a single surface and if you use [divide surface] it will divide each of the original surfaces separately.

Your best bet is to try to rebuild it as a single surface. Something like exploding it, extracting the edges, joining consecutive edges and lofting/sweeping...

This is, of course, not possible for every set of surfaces, but from the image you posted it looks likes it's doable at your case. If you are having trouble please post your file so someone can have a look at it.

cheers,

nikos

Permalink Reply by ng5 Alex on January 24, 2015 at 3:17pm

Hello

in case you cannot rebuild it to a single surface it is better to have multiple surfaces instead of brep, because divide surface does not work with breps as input.

in the preview photo it seems that yours is working, so maybe your question is about "uneven" division of your surface.

check the following thread, i believe it has lots of answers about your question.

cheers

alex

Permalink Reply by James on January 27, 2015 at 6:12am

Thanks for the Answers,

@nikos,

well actually rebuilding it is not really an option, as the precise Shape and curvature of the surface is important.

So brep (same as polysurface?) would be good, but surface devide (and other companents) dont seem to work with Breps! Why? Is there an other way of dividing a"combined" Surface?

@ Alex,

(thanks for the link, Iwill have to check it out) one question is how to get evenly spaced divisions of the Surface, and the other question is how to get All my (3) Surfaces to be interpreted as one (Polysurf/brep)

I wasn`t aware that this could be a "not so simple question"

So thanks for you replies, when I´m at home I will upload the actual rhino file-

Maybe somebody has a solution or wants to give it a try.

cheers James

Permalink Reply by James on January 27, 2015 at 1:42pm

HI Guys, here is my Sarting Surfaces, (hope i did it right, internalise data?)

I´m very thankful for any good ideas :)

Attachments:

WingTest001.gh, 7 KB

Permalink Reply by Hannes Löschke on January 28, 2015 at 4:18am

Your case is very special and pretty simple at that.

If you can keep track of the order of your surfaces and make sure, the UV directions line up, you're pretty good here.

I swapped U and V for two surfaces in Rhino and added them in a left to right order. By providing a list of U divisions, the larger surfaces get more divisions as the smaller transitions.

Attachments:

WingTest001_HL.gh, 11 KB

Permalink Reply by David Stasiuk on January 28, 2015 at 4:47am

You can also take a mesh-driven approach. You'll need the Kangaroo plug-in to run this definition...you build up meshes from your base surfaces, combine them, and then sort the edges by warp/weft directions. Combine the curves from one direction (and make sure they're properly organized, left to right, bottom to top) and then you can subdivide them evenly and get a grid of points useful for rebuilding a base surface, panelisation, etc.

Attachments:

GridPolysurface.gh, 17 KB

Permalink Reply by Hannes Löschke on January 28, 2015 at 4:03am

"not so simple" is the key phrase here. Surfaces have an internal coordinate system of UV-coordinates becuase of how they are defined mathematically. All of the surface division components kind of use that UV-System. Problem is that those coordiantes in general do not smoothly continue for the next surface in a brep.

There are "simple" cases, where extending one surfaces UVs to the next seems trivial but you need to keep in mind that all components need to work for the general case.

AFAIK, there are no simple and ready to use solutions to globally panelize a Brep in GH. There are experiments using Kangaroo, you might be lucky to find a solution with Paneling Tools, you can try using Starling or you might leave GH and use Evolute tools in Rhino.

Permalink Reply by nikos tzar on January 28, 2015 at 5:04am

Hello James,

Here is what I meant by "rebuilding" your surface as one: