I'm still not sure I understand...
I have tried to re-create the process - it seems my problem starts with PhysX.
I start with a car model (body,wheels,interior,glass) and make a copy of the car body.
I create a tyflow event-add a birth object- and add the first car body.
I add a voronoi fracture to the first event, then add a scale operator set to 90%
This first event becomes my "particle bones" object
I add a tyParticleSkin modifier to the car body copy(re-named "bodyskinned"), and add the "particle bones" flow as the skin.
I then create a tyActor helper, align X , Y and orientation to the (hidden)car body and add "bodyskinned" AND the interior parts as the actor rig node. All of the interior parts have tyParticleSkin with nothing assigned as the skin. The actor will not accept them without skinning.
Z must be aligned to the ground plane.
I create a second tyflow- add a birth event- set to start and stop at frame 0 (total 1).
I add "position icon", speed, then I add an actor operator. Everything seems fine at this point.
When I next add the PhysX shape operator is when things go wrong - the skinned car body shifts out of alignment.
If I play the simulation, the body collides as expected, but the interior objects ignore the collisions.
I've found that if I enable position and rotation locks in PhysX and disable TyParticleSkin for the objects, the interior parts align, but I'm not sure this is the right solution - and really would like to understand why/how this happens and how PhysX handles convex shapes here...
I have tried to re-create the process - it seems my problem starts with PhysX.
I start with a car model (body,wheels,interior,glass) and make a copy of the car body.
I create a tyflow event-add a birth object- and add the first car body.
I add a voronoi fracture to the first event, then add a scale operator set to 90%
This first event becomes my "particle bones" object
I add a tyParticleSkin modifier to the car body copy(re-named "bodyskinned"), and add the "particle bones" flow as the skin.
I then create a tyActor helper, align X , Y and orientation to the (hidden)car body and add "bodyskinned" AND the interior parts as the actor rig node. All of the interior parts have tyParticleSkin with nothing assigned as the skin. The actor will not accept them without skinning.
Z must be aligned to the ground plane.
I create a second tyflow- add a birth event- set to start and stop at frame 0 (total 1).
I add "position icon", speed, then I add an actor operator. Everything seems fine at this point.
When I next add the PhysX shape operator is when things go wrong - the skinned car body shifts out of alignment.
If I play the simulation, the body collides as expected, but the interior objects ignore the collisions.
I've found that if I enable position and rotation locks in PhysX and disable TyParticleSkin for the objects, the interior parts align, but I'm not sure this is the right solution - and really would like to understand why/how this happens and how PhysX handles convex shapes here...