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 Flexor With 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 coveredin this book

• Something goodto look into

• “Paint” how mucha bone willinfluence 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 theshoulder…

• Experiment withweight painting!

Problems

JOINT DEGREES OF FREEDOM AND LIMITS• A way of restricting how the joint moves

• Found in the Attribute editor