My goal is to create a program that displays a skeletal based model, with the possibility to select individual bones and make them longer or shorter. This will be part of a character customization system.

What I'm currently doing is applying a scaling matrix in bone space that scales the bone along the X axis (its length axis). This works, but also scales every bone connected to the scaled bones (which makes sense in a bone hierarchy). I need a method to cancel out the scaling for the connected bones. I tried applying the inverse of the scaling, but this seems to introduce skewing in the connected mesh.

Does anybody know how to go about this, or knows about good resources dealing with this particular problem? Either my googling skills aren't that good or this is a technique that isn't being used often.

Any help is greatly appreciated.

Marco.

Could the skewing be because it's applying the inverse scale to the child bone's mesh in the bone-space of the parent bone? Try transforming into the child bone's space before applying the inversed scaleing matrix.

Quote:Original post by Marco81
I tried applying the inverse of the scaling, but this seems to introduce skewing in the connected mesh.

Apply the inverse parent scale....