Curved Curtain

[propstuff]

You could draw a squiggly line with the polyline tool to any shape you want and extrude it.

N.

[linus2003]

Hey,

does anybody know how to draw a curved curtain in VW 11. I already sed the spotlight curtain tool, made nurbs out of the created curtain but bringing this in curved form is silly...

thanks for any solutions or better a new curtain plugin

[islandmon]

Use a NURBS curve to create curtain profile and then duplicate it to the height and Loft the curves to create a Closed Surface ... simple ... elegant... and looks great. Takes about 10 sec. to make ...

[C. Andrew Dunning]

I'd echo the need from the original post.

Drawing "squiggly lines" is doable, but to get something that actually LOOKS like (and, is easily recognizable as) a curtain takes a good bit of time.

Using an extrusion of a curve is a quick solution, but doesn't look like a curtain in either 2D or 3D. Again, it needs to be easily recognizable (and not look like just another line).

When I've needed a curved curtain, I've exploded a curtain object and taken the first couple of curved and done a lot of radial copying. It takes an eternity, but looks good...

[islandmon]

Rarely is it necessary to create the entire length of a curtain with just a single long extruded curve. Easier to make one small NURBS curve symbol best representing the profile shape desired with the necessary attributes then array duplicate the symbol as required. Changes to this one symbol instance then remake the entire curtain and rendering is a snap. If the curtain has various patterns on it then more than one symbol may be required to model them effectively. Dup/array the symbol to achieve stacking.

[APE Design Ctr]

Islandmon, its a very nice approach, and it will save alot of headaches and speed issues.

Do you have any basic ways to approach the array, or simple calcs (especially circular, sperical, or curved arrays) that you have found over the years?

I find solid modelling can usually turn out heavy and slow.

Also, I once downloaded one of your files (I believe it was for the perforated sheet). I tried to go deep into the symbol as it was a curved piece with a hole cut out to try to determine how you built it.

I would really love to learn how to use NURBS modelling more effectively. I am sure its something different than solid modelling / then converting to NURBS? Sorry for the many questions in this post - but I would have a hunch that many are wondering the same thing...

[islandmon]

Eddie ... there are numerous standard recipes for creating all manner of arrays and I've developed quite a few of my own as well. Nevertheless, I always try to begin with a minimal surface or volume and then to find the most efficient way to model it into the desired configuration. NURBS offer incredible efficiency and ease of use. As long as a minimum of three NURBS curve vectors cross a 3D NURBS surface can be created ... then that surface can be transformed simply by the use of 2D trim lines or polygon shapes. There's an added benefit in that the NURBS on both sides of the trim are preserved for future use.

The curtain is an excellent tutorial for creation of a single NURBS fractal of a single normal area of the curtain then duplicating it to fill the space just as with the holes in curved perforated plywood sheet ( search forum for this example). The secret to NURBing is the use of the Loft Tool to create the 'solid closed surface' after the basic NURB surface is defined. Instead of extruding a 3D polygon to form a solid next time :

1) Create a NURB surface

2) Duplicate and move to desire thinkness above the plane

3) In orthogonic view Loft the 2 NURBS surface and select 'closed & solid&keep curves in the OIP.

show >preview> watch the redlines connect the surfaces of the solid

If it works ( usually yes sometimes no for various reasons ) then you get a NURBS solid that can be manipulated.

Actually I prefer NURBS to all other methods. NURBS rock ...

[APE Design Ctr]

OK Thanks for your time. So I want to create a NURBS curve with a hole in the centre, or possibly multiple holes.

Based on your suggestions above, I create a square from the rectangle too, or composing 4 lines together. Then I convert to a NURBS surface (Create Surface from Curves), and the lines turn red. Then according to your suggestions above, I can transform that surface by the use of 2D trim lines or polygon shapes. So I take a 2D circle, and try to 'Clip' the circle from the NURBS surface, and it tells me I have illegal objects ...

I must be missing the obvious here.

Thanks Islandmon!

Eddie

[islandmon]

Sorry -

1) Create 2d poly > convert to NURBS Curve ( NOT surface )

2) Dup & Move NURBS curve to ht of Z

3) Loft both these NURBS curves to create Solid

4) Create2d Poly shape of cut-out >convert to NURBS curve

& position as required .

5) Select protrusion/Cut-out tool

6) Select Extrude Curve Mode > select both the curve & then the solid

7) Grab the Extrude handle @ Curve and move into or out of solid

8) Addition or selection determined by menu choice @ Protusion/Cut-out

9) Enter

Bingo !

[APE Design Ctr]

Very nice, thanks for your help

Eddie

[Andrew Bell@NV]

quote:

---

Originally posted by islandmon:

4) Create2d Poly shape of cut-out >convert to NURBS curve

& position as required .

5) Select protrusion/Cut-out tool

6) Select Extrude Curve Mode > select both the curve & then the solid

7) Grab the Extrude handle @ Curve and move into or out of solid

8) Addition or selection determined by menu choice @ Protusion/Cut-out

9) Enter

Bingo !

---

You can just create the curve and use the Project Tool in Project and Trim mode to remove it from the nurbs surface, without even converting it to a nurbs curve.

[C. Andrew Dunning]

Back w. ideas...

Though not something that I need every day having a curved curtain tool was interesting enough that I posted a question to the VectorScript mailing list. Thanks to some pretty big "get me started" help from one of the other "listers," Eric Torola, I now have a basic Curved Curtain tool. Of yet, there is no error trapping and it is a one-time Arc -> Curtain "transformer" that lets the user set the pleat depth, pleat segment length, and overall height.

If you're interested, I've got what we've done so far posted at: http://www.landrudesign.com/public/CurvedCurtain.txt.

The next step is figuring out how to make this thing into a PIO, with a few adjustable parameters. As w. a number of other things regarding this idea that I've had to learn, this will be part of my learning curve, as well. I'm open to any ideas...

Regards -