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Hopper
11-07-2007, 07:15 PM
I attempted to find the solution to this, but came up empty.

I have a set of polys that I have edge weighted to straighten out some curves on a CC model. It is a symetrical model, so when I mirror it to complete the other half, any poly that had an edge weight assigned to it no longer does. I don't see this as being a "bug" because I am mirroring the geometry and not the acompanying attributes, so my question is: Would there be an easy way to maintain edge weights when I mirror?

Oh, and it also totally destroys the continuity. It not only removes (or "not copies") the edge weights, but it also places the points of connecting polys (non weighted) where they "would have been" if the others had kept their respective weight values.

Am I crazy? (don't answer that). Should I not be using edge weights to straighten CC curves (i.e make curved holes pointed). :bangwall:

The obvious solution was to simply re-assign the weights, but what a pain.

Thanks in advance!

Sensei
11-07-2007, 07:25 PM
The only tool which is not destroying CC edge weighting either 3rd party and built-in LightWave is EasySplit http://easysplit.trueart.pl
Here is video with CC edge weighting http://www2.trueart.pl/Products/Plug-Ins/EasySplit/Graphics/Movies/EasySplit_Edge_Weight_Preserved_1.mov

I can confirm that LW Mirror tool is destoying CC edge weighting..

voriax
11-07-2007, 07:25 PM
Edge weights in LW are still incompletely integrated. They will "break" when you try to do any multiplication-type functions on them, ie mirroring, cutting, extending, etc.
It's embarrassing, but no you're not crazy. :)

Hopper
11-07-2007, 08:10 PM
Thank you very much for the info guys. :thumbsup: At least I know what to expect now until it's fixed.

And nice plugin Sensei. I can see the ROI in less than a days worth of work! Well... of course my "work" is more or less practice at this point, but I'm workin on it. I don't think I'll ever reach the calibur of most of you guys, but I'm going to try nonetheless. :bowdown:

Surrealist.
11-07-2007, 09:13 PM
Even with working edge weights I am not a big fan of this method.

2 reasons:

1) It has only worked well for me in certain situations.

2) To get a smooth edge I seem to need lots of polys at render time anyway. This is the same in Blender and I can only guess it is the same in other packages.

For me, using geometry is far more predictable and versatile. And since it seems to get a good edge I have to render with more polys - in fact more than I would need in that situation - I just add the geometry and save polys at render time.

My tutorial shows very simple and predictable ways to get this effect with subpatches.

colkai
11-08-2007, 01:44 AM
IMHO edge weights have a long way to go before they are truly sorted.
My hope is that when (finally) Modeller gets a make over (be it as it's own "app" or within a unfied app), that these and many other edge / point issues and features are taken in hand and given a serious thrashing.

Hopper
11-08-2007, 10:34 PM
My tutorial shows very simple and predictable ways to get this effect with subpatches.
It does indeed. I've read it twice so far. :thumbsup:

I was being lazy and it got me into trouble. So much for the "wrong" shortcuts.

Surrealist.
11-09-2007, 12:39 AM
Twice? :) Alright! Have you tried any of the examples?

Castius
11-09-2007, 12:53 AM
A good workflow would probable be something like this.


Model using edge weights on one half.

test render in layout. (if needed)
Use APS in Layout using the edge weight to add geometry where needed.

Remove edge weights and add extra edge

Mirror

Hopper
11-11-2007, 09:59 PM
Twice? :) Alright! Have you tried any of the examples?
But of course! It was extremely informative and helped me finish another project I had given up on because I was so frustrated with subpatches and my lack of ability to control them. I appreciate all your efforts. :bowdown:

Surrealist.
11-11-2007, 10:14 PM
Awesome! Great job on the hammer. Really glad to hear the tut helped you finish that other project. :)

Giacomo99
11-12-2007, 07:26 AM
This might seem like heresy, but you don't have to model every single form with subpatches.

I only bring this up because the hammer seems an ideal candidate for polygonal modeling--it, and many other hard-surface forms, might be easier to build without using the Tab key at all.

BeeVee
11-12-2007, 07:37 AM
You certainly don't *have* to, but like Richard I find that using subpatches makes things more flexible - easier to add detail to, or remove detail from.

B

Surrealist.
11-12-2007, 01:27 PM
This might seem like heresy, but you don't have to model every single form with subpatches.

I only bring this up because the hammer seems an ideal candidate for polygonal modeling--it, and many other hard-surface forms, might be easier to build without using the Tab key at all.


You are right. And some things are easier - at least initially. And others might be easier period. You bring up a good point and something I have kind of grappled with a bit myself. My conclusions on it I go into a little in the little addendum "Uses for Subdivision Surfaces" (http://www.lightwiki.com/Uses_For_Subdivision_Surfaces). What I have found is that with poly modeling you have to triple anything complex or inorganic to avoid non planars which when you look at what SDS actually does at the rendering stage (http://www.lightwiki.com/Fundamentals_of_Subpatch_Modeling), that's what you get.

The earlier method just before we had SDS in LW was to use metaphorm subdivision and triple to get smooth transitions in form. The drawback with this method is, as soon as you get a scene with a lot of polys, which can happen very quickly, you have to then manage that scene with proxy objects. What the new technology of SDS brought us was a proxy object and the subdivided tripped object in one with the addition to control - at both the display and render stage - the subdivision level and thus manage the scene more efficiently and flexibly.

In the case of the hammer you have the smooth forms of the handle and the smooth transitions that take place on the head from a box shape to a cylinder. That would not be easy with polygon modeling but with an understanding of Subpatch forms this is a snap. I chose it for the end of that tutorial because it was a challenge to do something with such sharp edges (such as the claw) that transition into a smooth round head. And this is the challenge of all computer modeling: getting "sharp edges" that are not actually sharp.

Now as for simple hard forms such as a box with slightly rounded edges, (so it looks like a real world object), well, with the box tool you can do that. Or you can use Rounder. This brings up another issue: smoothing errors. Now that you have one flat surface and a rounded edge you have to apply one of the few techniques to deal with that to get a clean render since you only need smoothing on the edge. This is extra time and effort. With SDS you don't have to worry about smoothing errors until you get into real complex objects and you use a bad polyflow with triangles in the wrong places.

Now for some scenes maybe SDS is overkill and using simple forms with rounded edges and a solution for smoothing errors might be just the thing.

So no you don't have to model everything in SDS. But this is where the technology is headed, it is more flexible, all the sculpt tools use it, so I think it is a good idea to learn how to make even the simplest forms as SDS. Whether you actually use it in every situation or not is up to the needs of the job at hand and your personal preference. :)

Hopper
11-12-2007, 07:47 PM
...so I think it is a good idea to learn how to make even the simplest forms as SDS. Whether you actually use it in every situation or not is up to the needs of the job at hand and your personal preference.
And this is why I chose to do the tutorial. I knew the point wasn't to create a simple object because it makes for an easier tutorial to write. It was to illustrate the point that you "can" model simple objects in SDS that you could just as easily construct with simple polys, thus you shouldn't assume that SDS is reserved for only modeling complex curves and organics. I thought the point was well made, plus I now have a nifty new hammer to put in my next fruit-basket-wine-bottle-butterknife-marble rendering exercise in Layout! :hey:

...and of course, the most important point of all... SDS simply has a higher "cool" factor than polygonal modeling. You DO want to hang out with the cool kids right? :D

SDS = Stylin' Divided Surfaces.

Surrealist.
11-12-2007, 08:26 PM
Bingo.

Also I :D OL about the cool factor. Funny stuff man.