In this chapter, we’ll be taking a look at how to create a character rig. As an example, we’ll be using humanoid simple model (simple_model.casc file) included in the Cascadeur package.
Before reading this chapter, make sure you’ve done every necessary preparation described in the Rigging Guide chapter:
- Joint Mode should be turned on
- Prototype objects should be selected in the Visible and Selectable menu
- Rigging tool panel should be enabled
A model prepared for rigging should look something like this:
Here we have a 3D model with a set of joints attached. What we need to do is to create prototype elements for every joint in your character model.
1. We are starting by rigging the character’s spine, moving from the pelvis up to the head. In the Outliner window, unfold the Armature list
2. Select the first joint in the list
...this is a root joint. It is used in some 3D software to move a character as a whole. However, it should not be used for rigging. Select the next joint instead.
3. Now, we need to set the direction in which prototype elements will be oriented.
Orientation is determined by children of the joint we've selected. In our example, the pelvis joint has several children. We need to select one of them: one that is pointed upwards.
Hold Shift and click this joint to add it to the selection
Note: If a joint has only one child, we don't have to select this child when creating prototypes (as prototypes can only be oriented in one direction)
4. Now, we need to set the direction for the additional point controller.
For the spine, we want additional point controllers to face forward, so select Z from the Additional point in Axis group of parameters:
5. Click the Add rig element button on the Rigging tool panel. A set of prototype elements should appear.
Note that the additional point controller faces forward
Congratulations, you have just created the first element of your rig
Now we need to create the rest of the spine, which means our goal is to add a set of prototypes to every joint in the spine.
This can be done by manually creating prototypes for every joint (using the process described in the previous chapter), but there is also a way to speed things up.
6. Now, select the next joint - the same one you’ve selected in step 3
7. Then, hold Shift and select every following joint
8. Enable the Multiple Create option on the Rigging Tool panel
9. Once again, click Add rig element. This will create sets of prototypes for every selected joint
10. The end result should look something like this:
Now we have the main part of our rig. It is time to attach limbs to it.
Prototypes can also be attached to several joints at once.
1. disable the Multiple create option
2. Select the first joint in the sequence to which you want to add prototypes
3. Then, hold Shift and select the first joint after the end of the sequence
4. Finally, click the Add rig elements button to create prototypes
This technique can be useful if you want, for example, create a character with a rigid spine, or if your character's limbs have more joints than necessary
Limbs such as arms and legs are often symmetrical. We can use this symmetry to our advantage
We’ll start with the left arm.
11. Select the first joint in the left arm
12. Its name will become selected in the Outliner
13. In this name, find the part that that designates the joint as the one on the left side
For example, if the joint is named “arm_l”, this part is “_l”. If its name is “ArmLeft”, then this part is “Left”
14. Enter this part in the left text field on the Rigging tool panel, right below the Mirror create option:
15. Do the same for the right joint. This time, however, enter the text into the right field:
16. Enable the Orthogonal to joint fold option:
It is required if you want character limbs to bend properly.
17. Make sure that the Mirror create option is enabled
18. Create prototype objects for the joints in the limb
Note that the right arm will be created automatically
Now we have our limb rigged. However, we also need it to bend properly: not in any direction, but across a bending axis
Cascadeur can determine the bending axis automatically if the Orthogonal to joint fold option is enabled (this is why we previously turned it on).
Note: This only works if the limbs are bent - at least a little - by default. If they are not, we recommend to bend them manually by selecting joints and moving them using Manipulators.
To create a hinge:
19. Select additional point controllers of the joints you want to connect.
20. Click the Union to hinge button:
21. Create hinges for the legs in the same manner
22. This should be done for every pair of joints that should be connected using a hinge:
Creating a hinge connection also creates a direction controller for it. If you don't need it, select it and click the Delete rig elements button
This is how the prototype for our rig should look once we're finished with the limbs. Now, it is time to add some finer details to our rig
For smaller parts, such as fingers or clothing elements, we don’t need rigid bodies. However, we still want to be able to animate them.
Pieces like these can be rigged using only box controllers:
23. Check the Only box controller option
24. Select the joints you want to rig
25. Click the Add rig element button
This way, minor parts of the model can be rigged
Now, every joint in our character has a set of prototypes attached to it. But there is still one thing we have to do before finally generating our rig.
Sometimes, a character model includes objects that are attached to the character. This may include certain parts of the outfit (such as shoulder pads, bags/pouches, etc.) or something a character holds in their hands (such as tools or weapons). Objects like these should not warp along with the character's body. However, you still want to be able to animate elements like these.
These objects can be rigged in the usual way. However, after creating proto rig elements for them, you should:
- Select the rigid body associated with the objects
- In the Outliner, open the Proto union component panel
- Disable the Bind with parent option
After this, the object will be excluded from Inverse Kinematics simulations (meaning that moving it won't influence the character's body parts). However, Forward Kinematics will still work for it, so it will move along with the body part(s) to which it is attached, and it can be animated using box controllers.
Prototype rigid bodies are always created with the mass equal to 1. In reality, however, different body parts weight differently.
Setting appropriate masses is necessary if we want our character to move in a physically accurate way.
26. Select a proto rigid body
27. It will also be selected in the Outliner
28. In the Outliner, find the Proto Union Component tab
29. On this tab, find the Mass parameter
30. Use this parameter to set the mass for the rigid body
31. Repeat the process to set an appropriate mass for every proto rigid body in the rig
Typical masses for the character body parts can be found on the dedicated page
This completes the process of creating a prototype for our rig. All is left is to convert it to a real thing.
32. Save the scene to a file
33. Make sure that the Delete proto objects after create option is unchecked
This way, you’ll be able to re-generate the rig if necessary
34. Click the Create rig button
After a short wait, your rig should be generated. Switch to the Point Controller Mode to test it
And this is how rigs are created in Cascadeur