Your setup consists of the body that is animated with weighted bones. Your Cloth Object is tied to the body in strategic places by creating a vertex group used in the Pinning of Cloth section. The Cloth Object also uses an Armature modifier. The same places where the cloth is pinned it must also have a weight map for the bone(s) it is pinned to, otherwise it remains tied to world space.
The Collision Object only needs to approximate the body for collisions. It should not have any facial detail, fingers, toes or anything that doesn’t directly collide with the cloth – otherwise the simulation will take longer. Remember the computer has to calculate each point in both the Cloth Object and the Collision Object. For rendering, you only need to include the parts of the high-definition body that will be seen.
Much experimentation can be done at the modelling stage to anticipate what will happen when the cloth drops onto the body. Think of it as holding the cloth in the air in certain ways to create an effect when it falls over the body. In this example, the solution for the armpits was to virtually remove them. They will not take part in collisions because they are fixed and also covered by the cloak’s hood.
Vertex maps are not only a part of weight painting and pinning, they can also be used to paint areas of the cloth where you want to have more stiffness and/or hold the shape. This is controlled in the Cloth Stiffness Scaling tab. Where the Weight is 0%, the values in the Structural or Bending settings will be used. Where it is 1-100% it will use the Structural Stiffness and Bending Stiffness depending on the weight value.
Make sure the Cloth Object and the Collision Object are in the same layer. Then you can play the animation to calculate the cloth simulation. Depending on your objects and computer, this can take a while. Experimentation with your system and your patience will determine how many polygons to throw at it. When the simulation is done you can use Current Cache to Bake which will preserve it after you save the file.
After you have the simulation baked you can then add more modifiers on the stack after the cloth such as the Subdivision Surface or Displacement modifiers. If you try to do this or try to edit your object before you bake you will have to run the simulation again. You may also want to paint Bump maps or even use Displacement maps for some finishing touches to add more detail such as folds or seams.
It has been my experience that using a simple quad mesh for the Cloth Object is best. Modifiers can be added after the simulation is baked for smooth rendering or displacements.
Blender cloth can be very bouncy and unruly. After much experimentation here are some key settings that help tame the Cloth Object for animation. The rest of the values can be left at the Cotton default.
We used the settings as follows: Gravity: 10.000; Collision Distance: .010-.020; Collision Quality: 5; Self Collision Quality: 3; Structural: 7.5; Bending: .250; Spring 50.000; Air: 10.000; Structural Stiffness: 12.000; and Bending Stiffness: 13.000.