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1Garrett
07-02-2017, 01:40 AM
Hello everyone and sorry for a new *super* newbie question, I tried also to search the forum without success... I'm trying to rig with a Genoma human biped preset a model of my own, its not a "normal" human as ypu can see in the picture:

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The main problem with this rig is with the bones that are wider than the model parts themselves (arms, legs...), since while the stretch function works as I want with model parts, it doesn't work how I hoped with bones (if I enlarge the bone vertically, the width becomes wider as consequence, I cant fix the stretch function width scale with bones). All the tutorials I saw on rigging have the bones "smaller" in width than the model parts. The question for the experts is the following: what is the appropriate manner to rig a model like this? Is "normal" or "possible" to have bones wider than the legs/arms? (I also weighted the model but I have problems with the legs that rotate wrongly when I move the foot behind in the Layout, I don't know if the problem is with the bone width... I wish for first to have some suggestions to arrange the model rig to the best. Many many thanks for answers!

Surrealist.
07-02-2017, 01:46 AM
I am not sure that I will have the best answer. But I will give it a go. One solution might simply be to use weight maps rather than bone influence. "Use Weight Maps Only" will cause the points to rotate from the bone pivot exclusively - based on weight influence. Not sure how stretching works but I would assume it would affect the points in the mesh in a similar way.

CaptainMarlowe
07-02-2017, 01:53 AM
The bones width shouldn't be an issue, but as Richard said, weight your various parts and use bone weight only. As for the leg rotating wrongly, it could be a fine tuning needed in Layout with poles (pyramidal nulls that can correct the orientation of the leg), or a problem of pre-bending when you created your mesh in Modeler.

RebelHill
07-02-2017, 05:08 AM
The drawing size makes no difference, its just an icon.

1Garrett
07-03-2017, 01:50 AM
I am not sure that I will have the best answer. But I will give it a go. One solution might simply be to use weight maps rather than bone influence. "Use Weight Maps Only" will cause the points to rotate from the bone pivot exclusively - based on weight influence. Not sure how stretching works but I would assume it would affect the points in the mesh in a similar way.

Thanks Richard, while I'm far away from fully understand the interaction between bones, weight maps etc.., your hint on using "Use Weight Maps Only" bone properties option helped so much with some bones (I used it just in bones where it solved wrong skin deformations). Since I like general rules to try to simplify my workflow , I'm assuming for now (at my current level of experience...) that using only weight maps is good for model parts that don't need skin bending but just rotations, like in my "robotic" model.

1Garrett
07-03-2017, 01:56 AM
The bones width shouldn't be an issue, but as Richard said, weight your various parts and use bone weight only. As for the leg rotating wrongly, it could be a fine tuning needed in Layout with poles (pyramidal nulls that can correct the orientation of the leg), or a problem of pre-bending when you created your mesh in Modeler.

Thanks for your answer, for "poles" you are talking about items of the rig after you press the "Create rig" in the Layout? Since moving around some of these objects (with cube form, not pyramidal) helped a lot for correct legs rotations. Sorry for confusion!

Surrealist.
07-03-2017, 04:28 AM
You can use weight maps for bending as well. But it works real well for robotic characters. For bending parts you have to assign a gradient of influence across the mesh. Too much to explain about here. But check out some tutorials on this subject. Usually people use weight maps along with bone influence to combine the two. With "Use Weight maps Only" you have to be more accurate in painting them. But this works perfect for robotic parts where you can assign one map to each part rather than blend, and that is what you want.

He is just something I found quick:

https://www.lightwave3d.com/learn/article/lightwave-115-weight-maps-and-rigging-in-genoma/

Dodgy
07-03-2017, 06:43 AM
In the Bone panel, you can set the width of the icon size at the bottom of the panel. This will not affect the strength of the bone, just how it is drawn.