Gradual deformation

Hi, I'm new on Grasshopper and this forum, and I'm continuously facing problems modeling with GH.

I'm working on a stereograph light (This kind of thing :http://www.thingiverse.com/thing:202774), so here's my question: I want to deform the internal sphere so that it creates "moutain-like" forms around the holes, matching the ones of the external sphere. Do you thing it is possible? And how could I do it?

Below, a look at what I'm talking aboutThank you for reading

Attachments:

Chambre Noire Grasshopper.gh, 55 KB

Replies to This Discussion

Permalink Reply by peter fotiadis on November 17, 2016 at 1:37am

That's easy but very slow (say with SpatialDeform [BTW: 2 native GH components available] and/or via direct C# coding).

Allow me some time to test some faster way (say: using meshes instead of nurbs surfaces).

Permalink Reply by Malvin Boutier on November 17, 2016 at 3:13pm

Thank you for your reply Peter.

I tried using SpatialDeform but couldn't find how it works, I don't understand what's needed in 'syntax' (points?). It also tells me I'm not using the same number of data, whereas I have the same number of vectors and point pairs.

I also tried Point deformation but the same error occurs.

Here are my results:

Do you have any idea?

Attachments:

Chambre Noire Grasshopper2.gh, 21 KB
Chambre Noire Grasshopper3.gh, 25 KB

Permalink Reply by peter fotiadis on November 18, 2016 at 4:49am

Well .. I have several C# thingies that do orthographic projections (and the inverse) but I'm not in the practice right now.

In the mean time ... get this attached that does a "similar" (so to speak) job using the Sporph Morph Method (bonus: a freaky Mobius transformation). The input is via another C# that does random grids of rectangles.

Note: brep with holes and thicken BrepFace (both sides at once) are SLOW (these options are controlled via the mapObjects integer parameter).

more soon, best

Attachments:

map_to_surface_V3.gh, 141 KB

Permalink Reply by peter fotiadis on November 19, 2016 at 1:23am

Find a couple of minutes more for something that is closer for your goal.

Works in 3 modes:

The "fast" (rectangles are "projected" to the sphere having a variable "focus" point in mind. In fact is rather slow to be honest; BTW: a Demo shows what goes where):

The slow (a drilled brep is made [requires ~double the time]):

The VERY slow (thickened [both sides at once] drilled brep):

Note: thicken both sides a BrepFace is TRICKY and may yield bananas if the topology and the thickness "mismatch".

have fun(?), best

Attachments:

map_to_surface_V4.gh, 129 KB

Permalink Reply by Malvin Boutier on November 19, 2016 at 6:14am

Thank you for these answers! I'll try it out and come back here to tell you if it works for me. :)

Permalink Reply by Malvin Boutier on November 23, 2016 at 7:47am

After trying your files, I couldn't figure out how to use the indices, there was always one "branch" item in red (the one below the first).

As far as I can see, I still can't modify the surface according to the edge of the holes... Any idea?

By the way your files are crazy, good job!

Permalink Reply by peter fotiadis on November 23, 2016 at 10:23am

Well ..

1. By "indices" you mean the branch stuff for the Demo? If yes since this is done via native components no "smart" (so to speak) checks are included (meaning that if a non existing branch is called on duty > the component protests accordingly). If you want to see what rectangle goes where ... in a "safe" way ... I could "remake" the Demo via code (very easy).

2. What means modify the surface according to the edge of the holes? Provide some sketch (by hand). That said the surface (Sphere in this occasion) is "static" in the sense that is "affected" (it's drilled or drilled and thickened - if you want it) by the "projected" rectangles (as Curves) and not the other way.

BTW: crazy files? not at all I confess > but if you are brave enough ... I could provide some ultra freaky things, he he.

Permalink Reply by Malvin Boutier on December 1, 2016 at 11:20am

Hmm what I mean by modifying the surface, is to deform the surface around the holes, using the edges as "controller" (See the drawing).

My final goal is to obtain a "hazardous" shape the will project a paving already defined.

I think I could be brave enough to see what things you've got!

Permalink Reply by peter fotiadis on December 2, 2016 at 12:19am

Hmm ... this indeed requires bravery + Karma + serious espresso reserves + some cigars.

One way is to create a "proper" Mesh (using MeshMachine: very tricky) out of the "drilled" BrepFace and then locate the inner loops and modify the vertices "outwards" (and rebuild the corresponding mesh faces). All n all: a rather very easy task.

Then paint the mesh lime green and relax it using Kangaroo2 yielding an ugly paranoid thingy - like a Shrek with many mini "short" ears.

Then thicken the mesh (yikes).

I'll try something similar this w/e (but I hate meshes like my sins).

Permalink Reply by Malvin Boutier on December 2, 2016 at 9:48am

Here is what my professor went with. This is the most accurate thing he's been able to create but the problem is: the list of curves are not read in the same order on both sphere edges and extrusion edges, whereas it worked yesterday... i'll try your method too, hoping it will work!

Attachments:

Chambre Noire.gh, 26 KB
Paving.3dm, 232 KB
Result.3dm, 652 KB

Permalink Reply by peter fotiadis on December 2, 2016 at 10:41am

Well ... the "method" briefly outlined above works (given a generous doze of Karma with regard MeshMachine) but dealing with the "naked" mesh vertices (inner loops) to "distort" without coding ... hmm ... maybe/probable is doable with native GH stuff but is not my style.

Anyway IF you attempt to do it without C# ... try to avoid a mesh with a gazillion vertices (for some kind of "real-time" response at mesh relaxation phase).

On the other hand you can "skip" the move outwards all naked vertices part ... and work with K2 VS the mesh as "it is" (anchor points = all naked vertices).

more soon.

Permalink Reply by peter fotiadis on December 3, 2016 at 2:49am

Well ..

I've modified your mesh by adding some holes in order to avoid the obvious (in fact this is very naive way to skin the cat: we need a (rather complex) policy for keeping all the nodes that are NOT "related" with your OE holes at bay).

Ugly news: Lewis H lost the F1 championship due to a rather obvious Mercedes conspiracy > therefore I'm in constant depression and I can't write a line (or two) of proper code > life sucks.