# GL Line Structure -- scale in 3D?

Using the Kineme GL Line Structure inside an iterator, inside a trackball -- Is there a way to have a line drawing and scaling in 3D space using the Kineme GL Line Structure? Or is there another tool for this job?

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### Re: GL Line Structure -- scale in 3D?

hi,

try Kineme GL Scale. (in SL the 3dtransform has scale option as well)

d.

### Re: GL Line Structure -- scale in 3D?

I haven't used either patch, but I know a little about OpenGL and very little about math.

In the mathematical sense, as well as to OpenGL, a line only extends in one dimension. IIRC, in an OpenGL line structure, you can set the stroke width, but that's a uniform setting. It doesn't scale by perspective.

What you need would be an extruded cylinder (or extruded + shape) of polygons.

Again, that's how I understand it, but I may be too out of touch.

### Re: GL Line Structure -- scale in 3D?

Thanks for the replies. I am using SL. 3D transformation and GL Scale do not do the deed. Makes sense that the line is 1D. I guess there are no other line tools with width responsive to 3D? I'll look into extruding a cylinder or polygon -- done that before with the 3D parametric solid tool. Maybe could use the built in cylinder, too. Good tip, thanks.

### Re: GL Line Structure -- scale in 3D?

Try using the 'Kineme GL Depth Sort Sprite' together with Iterator and Replicate in Space:

See the composition in action here: http://www.youtube.com/watch?v=XWBeowqLO70

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FreeMotion.qtz8.3 KB

### Re: GL Line Structure -- scale in 3D?

This is an example of using the GL scale to change apparent z scaling on group of lines. Amp up the z scale and see what I mean.

This is the basic macro I started my "gt lines app" stuff with. The javascript queue can also be changed to add in a manual z val, instead of writing it at 0, if a decent way for controlling the z was established (maybe 2 finger scroll or something... might be good for multitouch actually!).

(FWIW, the composition above starts glowing and then plummets to sub 5fps... I think something may be awry.)

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line zigzag_gt.qtz34.1 KB

### Re: GL Line Structure -- scale in 3D?

yes you're right, the FreeMotion.qtz composition will drop in fps if the midi control data isn't input. I should have mentioned that a signal pulse (from a MIDI control source in this case) feeding into the Integrator patches will reset them, otherwise the number of copies will keep increasing hence the drop in fps.

### Re: GL Line Structure -- scale in 3D?

Thanks so much! I'll have a look later today.

### Re: GL Line Structure -- scale in 3D?

Both comps are interesting to see. Thanks again.

GT -- That's a useful lesson in there. Actually, I got a little giddy when I saw that one working. F-in' awesome! Very generous. Puts me on the right path and more.