How to make a net?

petropix · 7 Jun 2012, 21:50

Hello All:

I'm trying to make a net or otherwise dome-like tubular structure. Any way to drape a grid of lines on a curved surface and then convert the lines to tubes? (the easy way Here's a half-hearted attempt.

Thanks.

pilou · 7 Jun 2012, 22:05

Line to tube by Didier Bur

and all Extrude edges and aespecially Extrude edges by rail by face by Tig

But don't wait miracles for the intersections for close up! ; )

brookefox · 7 Jun 2012, 22:23

one of the sphere or other similar draw shape plugins
distort it to your liking; subtract the bottom half perhaps.
as the maestro says, use line to tube to make the structure 3d or maybe pipe along path or maybe some other.

It is required that you post your results here. (See clause 4995.b.645.jd, subsection 2 of your user agreement.)

petropix · 7 Jun 2012, 23:00

@brookefox said:

one of the sphere or other similar draw shape plugins

distort it to your liking; subtract the bottom half perhaps.

as the maestro says, use line to tube to make the structure 3d or maybe pipe along path or maybe some other.

It is required that you post your results here. (See clause 4995.b.645.jd, subsection 2 of your user agreement.)

My apologies. Extruding lines to tube or pipe is not the difficulty. Nor is creating a curved or spherical shape. Draping, or otherwise bending a symmetrical grid pattern onto a curved surface is the devil here. To draw each line individually and space it equally is what I find daunting, and I was just wondering if anyone knew of a more expedient way.

Thanks.

pilou · 7 Jun 2012, 23:16

Drape is not sufficient ?

You can also use Tools on surface by Fredo6

petropix · 8 Jun 2012, 01:57

@pbacot said:

You have to decide what sort of framework you want and what is mean by equally spaced. Is something like this what you want in terms of lines? (given you can produce the tubes as you said, I haven't bothered). this is derived from a follow-me lathed dome. Copy and paste the lines under the wireframe setting.

Many thanks! Yes, this is getting closer. Copy and paste the lines from wireframe view. Brilliant! Why didn't I think of that?

pbacot · 8 Jun 2012, 02:09

I hang around here a lot (by my posts 1000 times more than you ) that's probably why.

Here I have done some manual (follow me) tubes on the structure just to see. the rings and the rib are each solid groups. the whole mesh beyond is one solid group. Obviously you can radial duplicate that rib add rings etc.

pbacot · 8 Jun 2012, 03:18

You have to decide what sort of framework you want and what is meant by equally spaced. Is something like this what you want in terms of lines? (given you can produce the tubes as you said, I haven't bothered). this is derived from a follow-me lathed dome. Copy and paste the lines under the wireframe setting.

brookefox · 8 Jun 2012, 04:11

Unlike Pilou, I am not above crying "Foul!"

(As foul as that may be.)

(Even chopped liver has rights.)

pbacot · 8 Jun 2012, 04:24

Time out Foul? Fowl?

brookefox · 8 Jun 2012, 04:40

Yes!

Play on!

pbacot · 8 Jun 2012, 15:05

Well yes.
Brookefox's original recommendation should get you there.

The selection using wireframe is a nice gimmick. But just using Didier's excellent "line to tube" ruby, you don't have to do that. You do have to unsoften the lines within the hemisphere. The ruby helpfully groups the result separate from the lines.
The issue is determining what sort of sphere framework you are looking for. You could also use a geodesic dome. But here is a result with my frame using the "line to tube" ruby. Much better than "manually" constructing it.

What did you come up with PetroPix?

petropix · 8 Jun 2012, 16:55

@pbacot said:

Well yes.
Brookefox's original recommendation should get you there.

The selection using wireframe is a nice gimmick. But just using Didier's excellent "line to tube" ruby, you don't have to do that. You do have to unsoften the lines within the hemisphere. The ruby helpfully groups the result separate from the lines.
The issue is determining what sort of sphere framework you are looking for. You could also use a geodesic dome. But here is a result with my frame using the "line to tube" ruby. Much better than "manually" constructing it.

What did you come up with PetroPix?

Okay you two love birds-- settle down! I can't wait for when I ask, 'How to Make a Nest?'

Anyway, I'm working on it, working, working-- and I suppose I'm now on the hook for posting a tutorial here. Fair enough, I love this forum-- now where WAS I?

brookefox · 8 Jun 2012, 17:22

I failed to mention the wireframe, edges only selection as I thought it was clear. Seems it was not, but as you say 'line to tube' doesn't require that.

Here's one with the non-radially faced sphere (dome), in which the faces are more approximately equal on the surface. If it is desired that the grid be regular before draping then take the faces only and drape the even grid from '(sandbox) from scratch' or other and drape as Pilou showed. Once draped of course the grid is distorted (except in ortho plan view).

brookefox · 8 Jun 2012, 17:24

@unknownuser said:

now where WAS I?

You were going to show us approximately what kind of thingy you were looking to model.

Gaieus · 8 Jun 2012, 18:15

Ah yes, I have built structures like that with those plugins, too...

[xxl-img:16r7n4hu]https://lh4.googleusercontent.com/-Vxt3eLcDCdA/SxpNB9vm88I/AAAAAAAAC2k/1nHsbF5c5wU/s800/gradem%25C3%25A5l.jpg[/xxl-img:16r7n4hu]

[xxl-img:16r7n4hu]https://lh5.googleusercontent.com/-4kst3gHb36M/SxpaUnwolNI/AAAAAAAAC3g/exM1-TYvIFw/s1024/grademal.jpg[/xxl-img:16r7n4hu]

[xxl-img:16r7n4hu]https://lh4.googleusercontent.com/-tLQYrxWR3xE/SxpaQYN4YhI/AAAAAAAAC3c/QuXctyi_tG8/s1024/example2.jpg[/xxl-img:16r7n4hu]

petropix · 8 Jun 2012, 19:06

@brookefox said:

@unknownuser said:

now where WAS I?

You were going to show us approximately what kind of thingy you were looking to model.

Well, actually -- it's a bungie cord net, about a foot square -- for strapping down cargo on, say, the back of a motorcycle seat. So there's quite a bit of deformity on the original form involved: bulge and elasticity. Challenging to draw with any degree of realism, however, that's not my purpose at this juncture. The net is a subordinate feature on a much more elaborate model. The techniques discussed here are enough for me to "fake" it for the interim. The model's over-all purpose is to show functionality of its various components, and how they relate to each other; it's not to win an illustration prize.

Many thanks!

yitzhar · 6 Jan 2013, 15:49

@brookefox said:

I failed to mention the wireframe, edges only selection as I thought it was clear. Seems it was not, but as you say 'line to tube' doesn't require that.

Here's one with the non-radially faced sphere (dome), in which the faces are more approximately equal on the surface. If it is desired that the grid be regular before draping then take the faces only and drape the even grid from '(sandbox) from scratch' or other and drape as Pilou showed. Once draped of course the grid is distorted (except in ortho plan view).

can you please explain how you made those constructions beam ? step by step ...