Hubs

A hub is a special type of CATBone that serves as an organizing device in the CATRig. Typically it’s a centerpoint from which spines, arms, legs, tails, and extra bones sprout. A hub can be a pelvis, ribcage, thorax, or head, depending on its function.

• Select or add a hub object. > Modify panel > Hub Setup rollout

The first hub created is the root object for the rig. In an upright, two-legged creature such as a human or a four-legged creature such as a horse this would be the pelvis.

Basic CATRig with CATParent below and hub (pelvis) above

Hubs on different CATRigs

Procedures

To create a hub, do one of the following:

• Create the first hub of your character by selecting the CATParent, and, on the Modify panel CATRig Load Save rollout, click Create Pelvis.
  
• Add a spine to a hub; this automatically creates an additional hub at the end of the spine.

To add limbs to a hub:

Note: When you add two limbs of the same type to a hub, the first limb is always the left and the second is automatically the right.
1. Select the hub to add a limb to.
2. To add a leg, do either of the following:
   • On the Modify panel Hub Setup rollout, click Add Leg.
   • In the viewport, right-click the hub, and from the lower-left quadrant of the quad menu, choose Add Leg.
   
3. To add an arm, do either of the following:
   • On the Modify panel Hub Setup rollout, click Add Arm.
   • In the viewport, right-click the hub, and from the lower-left quadrant of the quad menu, choose Add Arm.
   

To add rigging objects:

You can specify additional objects such as skin meshes, helpers, and so on, to be included in a custom rig when you add it from the CATRig Load Save rollout. This is particularly useful when you need props that a character carries, such as a sword or a book.

1. Add the rigging objects to the scene.
2. Select the hub and then click Add Rigging.

   This opens the Extra Rig Nodes dialog.

3. Click the Add button.

   This opens a version of the Select From Scene dialog labeled Pick Extra Nodes.

4. Highlight the objects to add and then click Pick Nodes.

   The highlighted objects appear in the Extra Rig Nodes list.

5. Close the Extra Rig Nodes dialog by clicking the Close (X) button in the top-right corner.
6. Select the CATParent and on the CATRig Load Save rollout, click the Save button. Give the rig a name and click Save.

   The custom rig is added to the CATRig list. Now, when you add this rig, the additional objects are added as well.

   Attention: To retain the added parts in the saved rigging, you must use the default CAT3 Rig Preset(*.rg3) file format. The alternative format, CAT Rig Preset(*.rig), does not support extra parts.

Interface

Name

The name of this hub. See Using CAT's Naming System.

Copy/Paste/Paste Mirrored

Buttons for copying and pasting the hub settings to or from other hubs. See Copying and Pasting Rig Parts.

Use Custom Mesh

Toggles the custom mesh for this hub bone. See Customizing the Geometry on CATBones.

Length/Width/Height

Define the size of the hub in CATUnits.

Add Leg/Add Arm

Add new limbs to the hub.

Add Spine

Adds a spine to the hub.

Add Tail

Adds a tail to the hub.

Add Bone

Adds an extra bone to the hub.

Add Rigging

Adds special rigging objects, such as props, to the hub. For details, see To add rigging objects:.