Negative scale in bone causes problems

Valmond · Post by **Valmond** » Thu Jan 14, 2010 1:49 pm

Hi everybody!

I have some meshes + animations that are causing me trouble but after a bit of research I found that some
of the bones have a negative scale (a sort of mirroring I guess) and that breaks the animation in Irrlicht.

So my question is, is there any easy way to 'normalize' this in 3ds max
so the animation (and rigging) stays the same but the bones would have a scale of say 1.0?

Sorry for being such a noob when it comes to the art part ^^

Thanks for your time!

hybrid · Post by **hybrid** » Thu Jan 14, 2010 2:28 pm

some issues with scale keys in Irrlicht have been resolved in version 1.7, maybe you can use it now. Besides that I have no idea how to do this in a modelling tool

Mel · Post by **Mel** » Thu Jan 14, 2010 4:33 pm

My guess in that matter is that in the program where you edit the meshes, bones and animations, the bones of one side were created cloning the bones from the other side, and then, were mirrored.

Although that could work well in the 3D editor, the problem is that the transformations of the bones were exported mirrored, and thus, the bones had that negative scale.

When you are making bones, don't clone and mirror them. Build new ones, it is slower, but their transformation matrices will be always correct.

Or else, as you say you are a 3DSMAX user, if it is a human like character, use a biped to rig it.

Valmond · Post by **Valmond** » Thu Jan 14, 2010 7:15 pm

Thanks Hybrid, I updated the latest Irrlicht and changed one of the
examples to run the animation but unfortunately it didn't change anything ^^

Mel, thanks to you too but I'm definitely not a 3D artist!
I bought those meshes and animations so It would take forever
for me to rig them correctly, not even talking about animating them :p

Any other ideas (or a magic converter maybe?)?