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Mat
03-14-2005, 10:39 PM
Hello

I've been working on my model for awhile now and I've come across a few hurdles my main problem arises when I attemp to setup joint morphs for the area where the legs join the body. If there is anyone who knows how to fix this problem or knows another method or tutorial that I may try I would greatly apreciate it.

Mdust
03-14-2005, 11:13 PM
Could it be the bone pulling on it? Have you tried messing with the inverse distance - to a higher level? Also a weight map?

It sems like something is pulling on it - like the bone.

Mdust

Celshader
03-14-2005, 11:34 PM
I'm not 100% sure what you're aiming for, either, but my knee-jerk reaction is that "Use Morphed Positions" might be the culprit. When "Use Morphed Positions" is turned off, those points will always "belong" to the bone closest to their unmorphed positions -- the thigh bone -- no matter how far away a morph target pushes those points.

When "Use Morphed Positions" is turned on, the points will be most influenced by whatever bone is closest to their positions, morphed or unmorphed, period. This means that the morph might be pushing the points far away enough that they fall under the influence of the bone now closest to them -- the hip bones, maybe?

If you are using "Use Morphed Positions" on purpose, I apologize for not being more helpful with this post. If you want "Use Morphed Positions" turned on, but you do not want those points to fall under the influence of a given bone, you might assign a weight map to that given bone to restrict its influence, so that it affects everything but those points.

$0.02 :o

Mdust
03-15-2005, 02:45 AM
Yea, if you don't mind me chiming in on that. It does look like the hip is pulling it away and if so you could apply a map as Jen says to those points and assign a negitive or zero value.

So Jen tell if I am right in this. What you mean is make an addition to the map already applied to the hipbone in the way of some negative or zero values to points that are on the inner thy. Correct?

If so would it also work to increase the inverse distance on that bone to say 128?

This subject is of great interest to me as well as I am currently studying it.

Thanks

Mdust

PS : Cellshader(Jenifer), I'm reading a book I believe you helped co-author right now. 1001 tips and tricks. Proton is all over it too - as you well know. A great read so far!

Celshader
03-15-2005, 05:13 AM
So Jen tell if I am right in this. What you mean is make an addition to the map already applied to the hipbone in the way of some negative or zero values to points that are on the inner thy. Correct?

If so would it also work to increase the inverse distance on that bone to say 128?

...

PS : Cellshader(Jenifer), I'm reading a book I believe you helped co-author right now. 1001 tips and tricks. Proton is all over it too - as you well know. A great read so far!

Well...I wouldn't use "Use Morphed Positions" on a character unless I had a reaaally good reason. I'd try turning it off, first, and see if that fixes it.

If Mat's using "Use Morphed Positions" on purpose, though, then he'll have to find some other way to keep those points locked to that bone.

The next-best way might be what you just suggested -- increase the bone falloff to ^128. I use ^128 on my characters, which keeps me from having to use more than one or two weightmaps. Mat's model seems to have few enough points that ^128 could work out fine. Again, though -- Mat might have a reason for going with ^16.

The third-best way is weight maps. If Mat wanted to recycle this rig for another character model, he'd have to make sure that the other character model has the same weight maps as the original model. So, the fewer weight maps the original rig uses, the easier it will be to recycle the rig for future characters.

---

There are two ways to use weight maps to restrict the influence the hip bone has over those points. One way is to create a weight map that says: "Back off, hip bone." A bone is only allowed to touch those points marked with non-zero values on the weight map assigned to that bone. So, any points you don't want the hip bone to touch, should have a weight map value of 0. Not negative, just 0. Or, instead of 0, just don't mark those points on the weight map at all. When the hip bone is assigned that weight map, it will only influence those points marked with non-0 values on the assigned weight map. If a point's not listed on the weight map at all, the bone won't touch it.

The other way to restrict the hip bone's influence is to bring in a limited-region bone, with its Minimum Range equal to the Maximum Range, to overpower the influence of the hip bone. The problem is, a limited-region bone set up in this way will grab all the points that it can. So, a weight map should be used to restrict the power of the limited-region bone. Select the two points that you want the limited-region bone to grab and create a weight map that represents just those two points. Spawn a child bone off the thigh, point it backwards and at those two points, turn on Limited Region, and assign the weight map to it. I've used limited-region bones like this to keep parts rigid, while using weightmaps to restrict their influence to only those parts I want kept rigid. I call them "pointlock" bones, myself, but you can call them anything you want.

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Glad to hear that you like the book! I did indeed write tips for it. :cool:

Karmacop
03-15-2005, 06:28 AM
Sorry to be stupid but ... is that zipper rigged? :eek: ;)

Mdust
03-15-2005, 11:46 AM
Glad to hear that you like the book! I did indeed write tips for it.

Cool, and thanks for all of that info on rigging! Great. I am soaking it all up.

Hope Matt gets it sorted out from what you provided too.

Thank you for taking the time. I'll put the data to good use.

Mdust

Mat
03-17-2005, 04:31 PM
Thankyou fellow lightwave users.

You have sertanly provided me with some usefull information
for that I can't thankyou enough. I shall endevour to follow your
instructions, and I will see what happens.

To answer some questions

I,m not sure why I used morphed positions, but I think I might
have been getting better results, anyway I shall check that.

karmacop Not sure I should answer this one but no.

thanks again see you next time.