it is possible to change the joint's rest transform?

is it possible to modify the rest transform of a joint at run time? it’s for something like skeleton shape keys for character morphing ,

I’m not entirely sure on this, but I believe that in Panda, the transform applied to an animation channel always completely replaces the transformation on a joint. So, while it’s perfectly possible to control a joint and replace its matrix procedurally, it would not be possible to change the matrix on a joint and have the node still affected by the playing animation, which I assume is what you’re after.

It is possible, of course, to add a parent joint with the transformation and control that one, which could be used to attain a similar result.

I could be wrong as I’m not fully familiar with the animation system.

a very inefficient solution is to have two separate models, one for animation and other for deformation, and relate each pair of joints of a same name with a morphing matrix , let call it Di, then expose all the joints of the animation model and control all the joints of the deformation model replacing each frame the matrix of each joint of the deformation model with Ai*Di where Ai is the current matrix in the animation model, you can’t change Ai, but you can change Di to achieve the desired effect,
the problem is that this is very inefficient, it will be great if panda had a procedure to change the joint’s rest transform/default value