Animated characters can participate in MassFX simulations as Dynamic and Kinematic rigid bodies. With the Dynamic option, a character can both affect and be affected by other objects in the simulation. Using the Kinematic option, a character can affect the simulation, but cannot be affected by it. For example, an animated character could knock down an obstacle in its way, but a large box falling on it would not change its behavior in the simulation.

The Ragdoll in MassFX is basically a convenience for creating and managing rigid bodies. However, it has several significant convenience features. For example, when bones are associated with a skin mesh, the Ragdoll can generate custom rigid body meshes based on the skinned vertices.

Creating a Ragdoll

To create a Ragdoll, select any bone in a set of linked bones (including bipeds and bone chains), or a mesh object with a Skin modifier that references the bones, and invoke the Create Kinematic Ragdoll or Create Dynamic Ragdoll command (for details, see MassFX Ragdoll). The skeleton does not have to be humanoid, or even represent a living being.

Creating the Ragdoll has several results:
  • Adds a Ragdoll helper to the scene. Use this object to set parameters for the entire Ragdoll, add and remove bones and skin meshes, and more.
  • Applies a MassFX Rigid Body modifier to each bone in the Ragdoll. The Rigid Body type is set to Dynamic or Kinematic, depending on which type of Ragdoll you create.
  • Adds a MassFX Constraint helper between each pair of consecutive bones in the skeleton, with the parameters automatically set to reasonable starting points for a ragdoll character.

The Remove Ragdoll command is a convenience for deleting the Ragdoll helper, all MassFX Rigid Body modifiers applied to the bones in it, and all constraints.

Tweaking Collision Shapes and Limits

You can edit the rigid bodies created by the Ragdoll individually by selecting the bone and adjusting the modifier settings as with any other rigid body or constraint. You can also use the Bone Properties rollout of the Ragdoll helper interface to batch-set common options on bones.

To apply common settings to one or more bones in a Ragdoll:

  1. If you don't want your settings applied to the entire Ragdoll, highlight one or more bones in the Bones group list.
  2. On the Bone Properties rollout, set the physical shape type you want, and whether the rigid bodies should wrap around the bones or the skin mesh using the Source setting.
  3. To apply the changes only to bones and groups highlighted in the Bones group list, click the Update Selected Bone button; otherwise, to apply the changes to all bones in the Ragdoll, click Update All Bones on the Ragdoll Tools rollout.