1. Computer Animation Ying Zhu Georgia State University
Cloth

2. How to create cloth? Create an object
Adjust the resolution of the mesh through subdivision
The more faces on the 3D model, the better the simulation result. (However, it’s also slower.)
Cloth is animated by simulating springs between vertices
Under Object (F7) and “Physics buttons” panel, “Cloth” tab
Press “Cloth” button

3. How to create cloth? Identify objects that may collide with the cloth
Make these objects “collideable “
Select the object
Under Object (F7) and “Physics buttons” panel, “Collision” tab
Press “Collision” button
Press Alt + A to start the simulation

4. Different types of cloth
As of 2.48a, Blender has pre-defined settings for the following types of clothes
Cotton
Silk
Rubber
Denim
Leather
You may create your own type of cloth through the “Custom” type

5. Cloth parameters In the “Cloth” tab
StrucStiff: overall stiffness of structure
Spring Damp: Damping of cloth velocity
Cloth is simulated by many springs between vertices
A higher “Spring Damp” means the cloth material appears “heavier” and “smoother”, with less jiggling.
BendStiff: how stiff the object when bended
Air Damp: how much the cloth “flows” in the air
Mass

6. Cloth and soft Body
Soft objects with closed surface are better simulated by Soft Body

7. Collision parameters for cloth
You can adjust the collision parameters for cloth in the “Collision” tab (next to the Cloth tab)
Collision is turned on by default
In most cases, you want to “Enable Self-collisions”

8. Collision with other objects
Any object that may interact with cloth should be made “collideable”
Select the object, under Object (F7) and “Physics buttons” panel, “Collision” tab (next to “Fields”), Press “Collision” button

9. Collision with other objects
Adjust collision parameters under “Soft Body and Cloth Interaction”
“Inner” and “Outer”: create a invisible “buffer zone” surrounding the object
So that the cloth will not collide directly with the object mesh
This is to prevent objects penetrating the cloth during the collision (due to imprecise calculation)
So if you see an object penetrating the cloth, adjust its “Inner” and “Outer” values

10. Bake
Like other physical simulations, you can bake the cloth simulation and then play it back without having to recalculate at each frame
“Bake” parameters are in the “Collision” tab
The bake “End” frame should be no smaller than the last frame of your cloth simulation

11. How to pin part of the cloth?
Sometimes you want to pin certain parts of the cloth so that those parts don’t move
The process
Select the object
Enter Edit mode
Under Editing (F9) panel, “Link and Materials”, create a new vertex group, give it a meaningful name
Select faces directly (or use weight paint to select faces) and then press the “Assign” button

12. How to pin part of the cloth?
Now go to “Object”, “Physics buttons” panel, in the “Cloth” tab
Press “Pinning of cloth” button
Select the vertex group from the drop down menu
Adjust “Pin Stiff” parameter
Press Alt + A, you’ll see that the selected vertex group is now pinned

13. How to attach a piece of cloth to an object?
Create a cloth mesh
Move it closer to the object you want to attach the cloth to
Make the cloth mesh a child of the target object
Create a vertex group on the cloth mesh and pin it using the previously mentioned method
The pinned part will be “attached” to the target object

14. Cloth and force fields You can use force fields to animate the cloth
Particularly the “Wind” force field
You may want to pin the cloth mesh first before applying the force field
Otherwise the cloth may be blown away
You may animate the strength of force fields by inserting key frames (or with IPO curve)
Change frame number, adjust force field strength
Place the mouse cursor in the “Fields” tab and press the “I” key

15. Apply the cloth modifier
What if you just want to drape a piece of cloth over a table without animating it?
Create the table object and enable “collision” for it
Place a plane right above the table and enable “cloth”
Increase the frame numbers (by pressing  key, don’t use Alt + A) until the cloth drapes nicely over the table
Now with the cloth object selected, go to Editing panel, in “Modifiers” tab, “Apply” the Cloth modifier

16. Apply the cloth modifier
When you apply the Cloth modifier, the cloth deformation become “fixed”

17. Re-enable Cloth modifier
What if you want to set up a starting shape for a piece of cloth and then animate it from there?
Use the previously mentioned method to fix the cloth object in a particular shape (by applying the Cloth modifier)
Adjust the frame number to the starting frame of your animation
Select the cloth object, go to the Cloth tab and press the “Cloth” button
Now you can animate the cloth from its “starting” shape (the Cloth modifier is back on)

18. Smooth modifier
You may want to apply a “Smooth” modifier to the cloth object
But the “Smooth” modifier should be added after (below) the “Cloth” modifier

19. Editing cloth parameters on the fly
You can let the cloth animation run in loops and adjust the cloth, collision, or force field parameters on the fly and see the changes in real-time
Open a timeline window
Press “Playback” and select “Continue physics”
Start the animation by press the Play button in the Timeline window (not Alt + A)
Adjust the parameters as the animation runs

20. Editing cloth parameters on the fly
For example, you may want to adjust the wind strength on the fly until you find the right number
This allows you to adjust parameters without having to stop and start the animation over and over again
The same applies to particle systems and hair too.