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paulhart
10-15-2004, 05:49 PM
I have created a mannikin like figure for a animation for a client, and have created and named all of the bones, created weight maps for each corresponding to the cut-shape that is the body part, and specified that only the weight maps are to be the influence when moved. I remain mystfied by way moving one bone "whacks" out the surrounding shapes in odd ways that I don't understand. I have tried to research the manual (7.5 and 8), 3-4 books, but I remain lost.... I appreciate any illumination that a wiser soul can offer. Thank you. The intent in this case is that they only need to move in the XY plane, heaven help me if I now add the Z axis, it is weird enough already....

GregMalick
10-15-2004, 08:01 PM
Isn't this an indication of a "Fall-off" problem -- of the bone influence that is.

spud_q
10-15-2004, 09:16 PM
You need to make sure you have the weight map only check box chosen in the bone properties panel. Also make sure that the right weight map is on the right bone.

Here is an example I set up for you. You can use this to make sure you have the same bone settings in your scene.

If you still have trouble or donít understand the process there are some good tutorials around you might make a note or something and Iíll post the links.

Good luck!

SplineGod
10-16-2004, 03:19 AM
If you are going to use weight maps, every vertex must have a weight map. No weight map is not the same as a weight map of zero value.

Every bone must be assigned to a weight map or else you may get unwanted deformations.

I would avoid using the "weight map only" option.

If you can avoid it I would not use weight maps and just use the standard bone falloffs ( I typically use ^128) or just parent the parts directly to bones.

paulhart
10-17-2004, 11:00 PM
Spud_q, Thank you for your response and the quick offer of a test scene. It was helpful, confirming that I was doing most things right, but "most" doesn't equal all, which is the requirement for it to work.
SplineGod, Thank you also. I went through methodically, opened and closed the files, re-exported after naming "everything" and thought all was fine until I went back into modeler and decided to now "thicken" the shapes and mirrored the sides, and then noticed that parts of the model were left behind when I moved the bones, and had to go back and assign the weights to both sides correctly again. It all seems to be working better now. You comment regarding every bone being assigned and weights "not zero" have an inverse effect was definitely part of the problem
Thank you both again for the assistance and directing me to where to look.
I have attached a low-res, early render, choppy but it clearly works.
Paul

SplineGod
10-17-2004, 11:09 PM
A simple way to check your weight maps is to select the move tool and hit the n key. Change the falloff to WEIGHT so now your move tool will only affect that weight map.
Move the points and see what does or doesnt move.
Open the vertex brower to quickly choose your weight maps to check.

paulhart
10-18-2004, 10:32 PM
Larry (aka SplineGod), Thank you..... Your tip on using the move tool to check to weight assignments is excellent. Very effective way of checking, found a couple of mistakes right off the way with some subtle weight issues that I wouldn't have found. I went back and selected the involved quads, assigned 100%, then inverted the selection and assigned 0% to the same weight map, more effective than my efforts of airbrushing the offending quads. It also got rid of some annoying flipping of the hand that had mystified me before... Thank you again for the first class tip.
Paul

Triple G
10-18-2004, 11:13 PM
Honestly, if I were you, I wouldn't even bother with bones at all in a situation like this. With a segmented character like this, just set up the pieces of your figure in the same hierarchy you would set bones up in. Position the pivot points in modeler accordingly, and in layout simply apply your IK options directly to the objects themselves. You not only have the advantage of not having to worry about improper deformations (because there ARE none), but because of this you can actually turn Layout's "Enable Deformations" tab OFF, and you'll likely notice a dramatic increase in feedback speed when you're animating. :)

SplineGod
10-19-2004, 12:16 AM
Hey Paul, Glad that worked out for you. I would also tend to agree with Triple G on this one. You could also just parent the pieces directly to the bones also.. :)

paulhart
10-19-2004, 10:26 AM
Triple G, Hello.. Thanks for the thoughts, I had decided that your idea would be the easy way, but thought that this particular project presented some interesting challenges to the bone weighting process, so I had used it as a push to learn. If I had been under more time constraints I would have taken your suggestion, and just gotten it done!!! I also didn't think that they would "stay together" without a lot of tweaking if I didn't "bone" them, but my understanding is that "parenting" them would accomplish the same thing, only problem is the schematic view, I only see bones and not "parts" or component pieces, so I was a little lost on this....
SplineGod, same issue, I had thought the parenting idea seemed to be on track, but scrambled around looking for how to do this and came away empty on that idea...
Thank you both for the help...
Paul

spud_q
10-19-2004, 10:50 AM
The schematic view should show absolutely everything. If youíre not in view of everything you can always put your mouse in window with the schematic and tap "A", which will fit everything to the view.

I must admit, I agree with Triple G as well. Bones in Lightwave are really for deforming objects. In other programs if you want to use an IK system you need to use bones but in Lightwave any parenting chain can become an IK chain. I would actually try and avoid using bones if at all possible, less going on in your scene that way.

Glad to see that youíre learning, weights are often a pain but, important to understand. Keep it up and good luck.

paulhart
10-19-2004, 04:29 PM
spud_q, Hello...
I do see "all" in the schematic view, and re-arranged them for best flow and understanding, however, I had put the figure on one layer with it's associated bones since the bones only work with elements on the same layer??? If I put all of the components on different layers (good idea for more complex projects) then how does the boning process work across the layers??? And parenting of just objects,?? just pull them under in the scene editor?? Again this makes sense if I have everybody on a separate layers, (which I have done on many other projects) but got confused as I try to learn effective weighting and boning principles.... Puzzled. Yes I do read the manual and multiple books, but this conversation and assistance has been more specific to my "stuck spot," and for that I am grateful.
Paul

spud_q
10-19-2004, 05:04 PM
:) ok youíve totally lost me. I'm trying to understand exactly what you're asking me here.

First of all bones must be the child of an object in Lightwave. If you want to do what SplineGod mentioned and parent the different objects to the bones you would need to create a null with a bone structure and then make each one of your object layers the child of a bone.

Yes the easiest way to parent objects in LW is in the scene editor, although you can also set parents to layers in modeler or in the motion properties panel.

Does that clear anything up???

paulhart
10-19-2004, 06:13 PM
Spud_q, Hello... I have attached a snapshot of the schematic for this particular layout for discussion. Besides the Camer and the light, the top corner element is just a projection background that has the final shape for reference at the end of the sequence and isn't lit for the render. The one in the center is the layer containing all of the body parts and branching out from under are all of the parented and linked bones for the figure. Hopefully this helps display both my process and my possible problems. Thanks for the response...
Paul