Creating and Editing Physics Constraints

Physics constraints can simulate physical effects on bones under gravity, wind, and spring forces. Virtual springs exist between bones with parent-child relationships.

Creating Physics Constraints

1. Select a bone to be constrained.
2. In the Properties panel, under the Constraints group, click the target setting button next to Physics.
3. The physics constraint is now created.

Editing Physics Constraints

1. Properties in the Physics Constraint group in the bone's Properties panel:
   • Translation X: Controls whether the x-coordinate of the bone is affected by physics. 0 means no effect, 1 means fully controlled by physics, and intermediate values indicate partial control.
   • Translation Y: Controls whether the y-coordinate of the bone is affected by physics. 0 means no effect, 1 means fully controlled by physics, and intermediate values indicate partial control.
   • Rotation: Controls whether the rotation of the bone is affected by physics. 0 means no effect, 1 means fully controlled by physics, and intermediate values indicate partial control.
   • Limit: Specifies the maximum force applied to the bone under physics.
   • Solving FPS: Indicates the frequency for calculating physics constraints. Higher values provide better effects but consume more resources. Generally, it's a multiple of the rendering frame rate.
   • Inertia: Represents the bone's ability to maintain its current velocity.
   • Force: Represents the magnitude of the spring force.
   • Damping: Represents the resistance the bone experiences. If damping is 0, the bone will continue to move indefinitely. Higher damping causes the bone to reach relative rest more quickly.
   • Mass: Represents the bone's mass. Higher mass means stronger inertia, making it harder to stop or start moving.
   • Wind: Represents the magnitude of horizontal force applied to the bone.
   • Wind Turbulence: Represents the magnitude of random horizontal force applied to the bone. It takes a random value within a range for each calculation.
   • Gravity: Represents the magnitude of vertical force applied to the bone.
   • Weight: Overall control of the proportion of physics constraint affecting the bone. 0 means no physics control, 1 means fully controlled by physics, and intermediate values indicate partial control.
   • Control: Operations for physics simulation
     • Simulate: Checkbox for real-time calculation of physics simulation effects. Checked by default; if unchecked, calculations stop and physics simulation effects won't be visible on stage.
     • Reset: Physics simulation is a continuous process. Reset restarts the physics simulation from the beginning.
     • Reset All: Resets physics effects on all bones on the stage.

Deleting Physics Constraints

1. Click the Delete button in the Operations section of the Properties panel to delete the physics constraint.