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Carbunkle
09-07-2004, 11:43 PM
Savoury salutations, everyone!

I'm having problems with parenting! (Who dosen't?!) I want to be able to parent one bone to a (detached) 'cluster' of other bones, but don't know how to avoid orienting the parent toward one of the bones in the cluster, if you see what I mean!

I can't find a way of preserving the parent bone's original orientation, so that in Layout, when I rotate the parent bone, the entire bone cluster rotates with it in unision.

I want to do this to use bones in Layout to produce sculpted endomorps, since I'm trying for as much precision as possible for joint compensation!

If there's any Lightwave guru out there with an altruistic streak, I'd be very oblidged if you could help me through this impasse!!!

Thanx and all the best!

Carbunkle!

faulknermano
09-08-2004, 03:57 AM
in General Options > Parent In Place

Carbunkle
09-08-2004, 09:28 PM
Many thanx, Faulknermano. I'll have a go at that one!

All the best!

Carbunkle!

uncon
09-08-2004, 09:45 PM
If parent in place doesn't work try talking to the children, or bribing them with candy to behave.

Carbunkle
09-10-2004, 08:57 PM
I've solved my parenting problems, at last - and not a candy bar or cross word in sight! I did quite a bit of parenting quite a while ago, but I'd forgotten, since I've tended to spend most of my time in Modeller! I guess parenting's just like riding a bike, and it gets easier the second time around!!!

I've had a go at using a cluster of bones to model endomorph joint deformations in Layout, and although I find it preferable to SoftFX - since you can move more than one point (bone) at a time, its still akward to use, and of course there's no other 'modelling' tools than move in Layout.

I'm going to put a new posting on the subject of RotateSkelegons, which is okay to use in Modeller, but I can't get it to work in Layout - the bones actually detach from the mesh when the two are linked via Expressions!!!

How do the rest of you Lightwaver's manage?

All the best!

Carbunkle!

faulknermano
09-11-2004, 03:10 AM
How do the rest of you Lightwaver's manage?

Carbunkle!
you mean joint morph deformations? if i need only general control, i go for "hold" bones. i also use endomorph-based correction, but i use it in tangent with the use weight map only option, so i can preview my deformations accurately in modeler.

Carbunkle
09-13-2004, 01:21 AM
Thanx for the tip, Faulknermano! I can't remember whether I activated the 'Use Weight Map Only' option the last time I used RotateSkelegons - but I'll have another go later on today!

Basically, I'm a control freak: I just want total control of how the mesh deforms when bones are rotated.

I used RotateSkelegons to make a corrective morph for bone rotation in Modeller, but in Layout, the bones detach from the mesh which gets massively distorted - and the bones don't even rotate the full 90 degrees that I'd defined in Modeller!!! (That is, when the morph is tied to bone rotation using Expressions).

This problem is starting to drive me up the walls!

Thanx and all the best!

Carbunkle!

faulknermano
09-13-2004, 03:22 AM
Basically, I'm a control freak: I just want total control of how the mesh deforms when bones are rotated.
ahh... that's just a phase. ;) imo, control is "relative" : if you know precisely how an element in lw is going to behave and use it to your advantage, than you can say you are in "full control." understanding lw behavior is key. :)

I used RotateSkelegons to make a corrective morph for bone rotation in Modeller, but in Layout, the bones detach from the mesh which gets massively distorted - and the bones don't even rotate the full 90 degrees that I'd defined in Modeller!!! (That is, when the morph is tied to bone rotation using Expressions).
weird... why do they detach? see if those detaching bones' position channels are moving (e.g. moving over time). they shouldnt. recheck their parents too. see if your expression are driving rotation channels only - they should.

Carbunkle
09-13-2004, 09:03 PM
Faulknermano, your're a font of knowledge! - thanx again! I will attempt to address this irksome dilema as soon as I finish keying this very post!

I don't believe there's anything wrong with my parenting - the bones are parented to their intended weight maps in Modeller!

I tend not to do keyframes, though, but leave the frame slider on zero. Wonder if that's affecting things?

Do you claim not to suffer from detaching bones, using the very technique that I previously described?!

I'm highly envious of your lightwave skills - I salute you!!!

Carbunkle!

faulknermano
09-14-2004, 02:59 AM
I don't believe there's anything wrong with my parenting - the bones are parented to their intended weight maps in Modeller!
i think we're not using the same terminology. :) just to be clear... you should say that bones are "assigned" to their intended weight maps. when you say parenting or parented, thats mostly referring to layout's bone structure. also, use the word "skelegon" when referring to bones in modeler. using these terms could you describe exactly whats doing on? is the popping happening in modeler? or in layout? are the bones popping themselves or is it the mesh that's being deformed?

Do you claim not to suffer from detaching bones, using the very technique that I previously described?!

the only time i've experienced detaching bones is when: 1.) i've somehow keyframed or expression'd a position channel, and 2.) using an IK goal which contains expressions on itself or downrange its children.

maybe it'll also help to post images (or a sample scene file) describing the problem, if it still plagues you still...

Carbunkle
09-14-2004, 08:14 PM
I sit corrected, Faulknermano!

Whilst awaking this morning I had an idea - as I frequently do! - about my detaching bones problem!

The bone hierachy dosen't actually come apart itself, you understand, but its rotation merely lags behind that of the 'fading in' morph: its almost as if the proportion of applied morph is different from that to the proportion of bone rotation! Result: that the bones stray behind and then out of the limb's mesh! Since the bones no longer reside inside the limb, this in turn causes the distortion!

My idea - I'll know if its a bright one or not after I attempt it in a minute! - is to straighten the bone - er, I mean skelegon! - in Modeller when using RotateSkelegons (rather than leave the skelegon in the rotated position in the endomorph, which is what I did).

I'll let you know how I get on!

All the best!

Carbunkle!

Carbunkle
09-14-2004, 09:49 PM
Well, Faulknermano, I'm affraid my bright idea turned out to be so dim you couldn't see it with a flashflight!

Its really strange! The bones only work as though they're assigned correctly to their weight maps when their rotation is not assigned to the corrective morph via Expressions!

As soon as I use Expressions to tie their rotation to the morph, they kind of slip out! As I rotate the limb bone, the limb's mesh seems to 'rotate' ahead: When the bone's at, say, 45 degrees, the limb's mesh looks as though its at 90! When the bone's at 90 degrees, the limb mesh looks as though its rotated by 180 degrees!

This is similar to what happens when, without using Expressions, you pull the morph slider in MorphMixer: the limb's mesh shortens because its a linear transformation, then regains its correct volume when its at 100%!

This problem is really holding me back! Excuse me while I sit in a quiet corner and have an intense migraine!

All the best!

Carbunkle!

faulknermano
09-15-2004, 12:39 AM
Its really strange! The bones only work as though they're assigned correctly to their weight maps when their rotation is not assigned to the corrective morph via Expressions!your statement makes me think that you may not have your weight maps correctly assigned to suit corrective morphing. correct weight mapping is the crucial step in corrective morphs.



This is similar to what happens when, without using Expressions, you pull the morph slider in MorphMixer: the limb's mesh shortens because its a linear transformation, then regains its correct volume when its at 100%!
yes, i do have a feeling (could be wrong) that your weight maps are the problem, assuming that you've followed the corrective morph procedure, presumably from the lw manual.

download this study i made some time ago: pardon if my language seems to take it as something of a novel idea; it was, back then....

http://www.geocities.com/lightwavespreaddepot/Morph_Tutorial.zip

a summary: modeler cannot (at least currently) mimick bones in layout. therefore, corrective morphs are hard to do and often not done with precision. however, there is a way for layout bones to imitate what we can do in modeler. so now, it's the other way around. using modeler's rotate tool to rotate, say, a forearm. when you do this in modeler, without falloffs, the deformation occurs in such a way as so make unsmooth parts particularly those close the point of pivot. paradoxically, this is what we try to achieve in layout. but such unsmooth places will later be smoothed out by our corrective morphs; we are totally dependent on the morphs to make these areas smooth. to achieve this hard modeler-like deformation in layout, we must assign only one weight map per-point. no sharing of two weight maps in one point. if we talk about an arm, select the bicep and assign a bicep weight map; then assign the forearm points with a forearm weight map. nevermind the abrupt change between forearm and bicep. deformations will always suck initially. but we have morphing to correct it.

more in the zip file. :)

Carbunkle
09-15-2004, 08:20 PM
Grateful greetings to you, Faulknermano! Many thanx for the tutorial which I will have a look at in a minute!

Before I embark on doing all my weight maps again (glad you can't hear the groan!), I shall also try another - hopefully brighter - idea than the one yesterday: I'll rotate the limb's skelegon in Modeller using RotateSkelegons, re-model any nasty distortions, then make the limb straight again! My fear is that its just a simplified version of the 'Apply Morph -100%' trick which I had problems with earlier!

This trick will probably end up on its knees coughing blood in the gutter too, but its worth a try!

I'll let you know how I get on! - thanx again and all the best!

Carbunkle!

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