CGDD 4113 SKINNING

WHAT IS SKINNING? The process of binding a skeleton to a mesh Methods: Parent binding Requires models to be separate Individual mesh is “parented” to individual bone Rigid binding Vertices closer to a bone will follow that bone Lattice binding Create a lattice deformer, rigid bind the lattice to the bones Smooth binding A vertex or CV can be influenced by multiple bones

PARENTING Each cylinder to each bone Test via rotations

RIGID BINDING Two skeletons, one NURB and one poly – each subdivided 10 Skin->Bind Skin->Rigid Bind

EFFECTS OF BENDING Polys are made of vertices NURBS are defined by CVs

MEMBERSHIP Edit Deformers->Edit Membership Tool

FLEXORS Type of deformer to prevent cracking Useful for polygons Without FlexorWith Flexor

SET DRIVEN KEYS Can set keys for the flexor in various positions Animate->Set Driven Key->Set The middle joint’s Y rotation will “drive” the points of the flexor lattice Note: When the book says “Zero the rotation”, just clear them in the channel box

LATTICE BINDING Create a lattice deformer for the polygon Rigid bind the root joint to the lattice Finish by changing the ffd1 node (local influences) to 4 Gives a much smoother appearance Easier to edit membership! Lattice CVs vs. vertices Can also use Driven Keys to define a bulge for the bicep

SMOOTH BINDING Skin->Bind Skin->Smooth Bind Sweet == true

WEIGHT PAINTING Not covered in this book Something good to look into “Paint” how much a bone will influence vertices

GETTING BACK TO OUR CHARACTER… Start by setting the preferred angle (RMB on the pelvis joint) Select only joints that should affect the mesh Best done in the Outliner view Use Smooth Binding! Wireframe turns purple Smooth bind the eyeballs

RIGID BINDING Eyes (to eye joints), eyelids (to head joint) and collar (to neck)

WEIGHT PAINTING Try bending the shoulder… Experiment with weight painting! Problems

JOINT DEGREES OF FREEDOM AND LIMITS A way of restricting how the joint moves Found in the Attribute editor