twisted lamp with variable rotation in different elevations

hi, i don't know what to do with this definition, i can't make the exact variable twisting along that cylindrical geometry.there's an image file and definition attached.

please help me with this lampshade design.

thank you all in advance.

Attachments:

twisted lamp.gh, 13 KB
twisted lampl.jpg, 63 KB

Replies to This Discussion

Permalink Reply by peter fotiadis on February 20, 2017 at 12:44am

Check attached. It works either using a curve or a line (as the "spine"). The radii of the circles (for Loft) can be either steady or random.The deformation can be linear or "progressive" according to some sin value. You can control the start/end index of the deformation (where it starts/ends, that is). The exterior profile curve is either an interpolated curve or a control points curve (use rather this option). At the final phase it can thicken the BrepFaces (due to Sweep2) at once in both sides yielding a closed polysurface (very slow: blame Rhino).

All decisions with regard the workflow are in red groups.

Shown the freaky option (using a curve):

The thickened rids (slow):

Attachments:

Twisted_ribs_entryLevel_V1.gh, 138 KB

Permalink Reply by peter fotiadis on February 20, 2017 at 1:04am

And a result using a line (as spine), random radii (Loft) and enable thicken.

Permalink Reply by zeinab gharbavi on February 20, 2017 at 3:29am

Thank you a lot peter for your great help,

it's a cool definition but it's got c# script for sine values. is there any way that i could get them without c# script? because i don't know anything about c# scripting......

Permalink Reply by peter fotiadis on February 20, 2017 at 8:17am

Hmm ... I confess that components are not (at all) my forte.

Here's a small challenge for you:

Given a data tree of points (derived from dividing a surface) how we can "insert" circles (or modified points as in the def provided already) with a "growing index" manner? Replace the circles with points (moved using the corresponding vectors and some amplitude) and you have half of what the C# does (actually a "bit" less ... since it makes some checks more to keep things under control). For the other half (sin distortion) I'll provide a similar example soon.

Doing the same with relative items is far more elegant but potentially confusing for a novice.

Attachments:

Twisted_ribs_the_challenge_V1.gh, 17 KB

Permalink Reply by peter fotiadis on February 20, 2017 at 8:40am

And a distortion using a graphical way.

The challenge for you is to control what happens if the rows, columns (i.e. branches and items) and the "growing" indices (concerning an item per branch for modification) mismatch.