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View Full Version : Reduce LWO to network of polylines?



jeric_synergy
07-15-2014, 11:49 PM
Given a mesh that looks like this:

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What's an efficient way of reducing it to a network of 2 point polys?


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tonyrizo2003
07-16-2014, 12:30 AM
Well, I'm not sure this is what you want but, all I did was;

1.) extrude on the Y axis
2.) then collapse it down to 0 on the Y axis
3.) merge points
4.) Open up stats window and select 2 point polys

Here is what I came up with.

meshpig
07-16-2014, 03:24 AM
Just use the sketch tool to trace the inner line then "K" to Kill the curve; then from the selected points; Create/Polygons ...More/ make polychain.

meshpig
07-16-2014, 03:55 AM
... pretty quick;

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alexos
07-16-2014, 03:58 AM
Yeah, or use select by normal on the two Y axes and get rid of the top and bottom polygons (you're going to have to freeze it first to preserve the small, smooth curves), then set value to zero, merge etc; but I imagine you want a single-curve network? If that's the case you would need to find some way to average the whole thing to a middle axis, which I have no idea how to do - and quite frankly I think it's just not possible, cos I just asked our AutoCAD wizards here it they could do it and they said "no way!", and if it can't be done within Acad, well...

I guess if you really hated yourself you could spend a few painful hours selecting point pairs and welding them on the average... Or just get rid of one "side" of the network and use the other as a starting point.

ADP.

jeric_synergy
07-16-2014, 08:04 AM
More info: the goal here is to get a low poly/point count mesh to use as a ClothFX proxy that calculates fast and then is linked to the heavy mesh via ....Metalink (?), so that deformation is fast and easy to tweak. This is a standard trick, but usually the meshes are a bit more regular.

2 point polys work fine for this purpose.

JoePoe
07-16-2014, 08:48 AM
If you reduce only to polychains won't you end up with the same number of points (and actually many more polys.... albeit 2 pointers)?

So is the actual issue here.... how to reduce this mesh?? Does it need to keep its Y dimension?

jeric_synergy
07-16-2014, 09:20 AM
You COULD end up with the same # of polychains, but that's not mandatory, and certainly not desirable..

Because of the nature of this particular mesh, a 2d polychain net is fine. I was saving the cylindrical version for my NEXT question. (I think it's Layer #2)

Greenlaw
07-16-2014, 09:31 AM
Doesn't StrandMaker do this?

Just checked...yes, it does. It's how the guides for the dream catcher was created in that early FiberFX demo.

To use it, select the mesh and just choose StrandMaker from Setup - FiberFX. The 2-point polychain version of your geometry will appear in the next layer. It's an easy way to make things like spiderwebs, nets, pretty much anything 'lacy'.

G.

jeric_synergy
07-16-2014, 09:33 AM
Strandmaker DOES do this, but as JoePoe said, the actual problem is to reduce the mesh. AFC, but perhaps the mesh that Standmaker generates (and it should really flash the status line, or switch to the new layer) would be a better candidate for reduction than the original mesh.

For simple objects, Standmaker works great.

Greenlaw
07-16-2014, 09:34 AM
Oh, wait...just took a closer look at the original image. Sorry, this won't work directly with StrandMaker. StrandMaker basically follows the edges of a mesh and converts the edges into 2-point polygons--I had only seen the thumbnail image at first and didn't notice it was modeled out. Sorry for the mislead.

JoePoe
07-16-2014, 04:48 PM
After letting it rumble around in the back of my head all day.....

Why can't we just use merge points?
I grabbed the top layer of polys, merged at 100mm. Excluded the edge points and kept increasing the distance.
I think I spent about 5 minutes "fine tuning" the result by hand.
The original result was more like 1K points but I ran reduce points once. Now it's 500ish (I think it's a little sparse in spots now. You still need enough to deform right? :))
It's no one button magic, but really not too involved at all.

Also pretty painless is just drawing splines over your shape in the background.
Maybe on a more complex shape that's not so practical, but in this case.... not terrible.

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jeric_synergy
07-16-2014, 05:46 PM
Merge Points was the first thing I tried, but I must have taken a wrong step.

Sensei
07-16-2014, 10:09 PM
What's an efficient way of reducing it to a network of 2 point polys?



Edge mode, lasso whole object, press ctrl-c, new layer, ctrl-v
you have 2 point polys only..