Set Driven Key

Set Driven Key (SDK) is very powerful and it allowed you to have a node��s attribute drive the attribute of another node. It��s very useful for animation.

1. While the pelvis still selected, go to Animate -> Set Driven Key -> Set option to bring up the Set Driven Key window.
Load pelvis joint as Driver, then select Jaw joint and load as Driven. Next, select Jaw from pelvis joint and rotate Z from Jaw joint. Make sure that pelvis joint's Jaw attribute and Jaw joint's attribute set to 0, then click on Key.



Jaw's value 0 (Min) has been set. Then I will set Jaw's value 10 (Max).

2. Key 10 for pelvis joint's Jaw attribute value, then -30 for Jaw joint's Rotate Z value. Click on Key.
Close the window and we have done.



Now, Let's test the Jaw attribute. With the Jaw attribute selected in pelvis joint, MMB click on the perspective window and drag it right to left and you will notice the jaw is open gradually.

This is only a simple example of how to connect a node's attribute drive the attribute of another node.
You may want to add other attributes to drive other node according to your setup.

Binding Character Geometry to Skeleton

Before I start skinning the dragon, I will parent its teeth and gum to respective joints. This is because there are no deformation needed for teeth and gum.



Hide the teeth and gum geometry after parented to joints.

There are 2 methods of skinning: Rigid Skinning and Smooth Skinning both involve the assignment of points on the surface geometry to joints in the skeleton. In this case, I would like to use Smooth Skinning to bind the dragon.

1. Before we start, I want to clear all the histories in geometry; this will avoid unexpected deformations.
Select all geomatries (except teeth and gum) and go to Edit -> Delete All by Type -> History.

2. With the geometry still selected, Shift-select the pelvis joint's selection handle to select the whole dragon skeleton hierarchy. Then choose Skin -> Bind Skin ->Smooth Skin option.

# Bind to: Complete Skeleton
# Bind Method: Closest Joint
# Max influences: 2
# Dropoff Rate: 4

Then click on Bind.

3. Select joints and move them around to see whether the skin behaves correctly or not. Then undo.



From the picture above, I need to fix it by refining the weight of the Smooth Skin bind. I will use the Paint Smooth Skin Weight tool. Skin ->Edit Smooth Skin ->Paint Skin Weight option to bring up the Tool Settings window, then paint weight values onto the different surfaces.

You can always place the character back to its original pose by Go to Bind Pose. Go to Bind Pose did not work if you translate the IK handle.

Select the geometry that you wish to paint weight, from the Tool settings window's Influences section, select the respective joint name, adjust the Stamp Profile value and start paint weight.



Basically, this is the method that I used to setup my character. You might need other methods to setup you character depend on how you want you character to be animated.