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Interface
Physical Properties
Mass A rigid body’s mass governs how the object interacts with other objects.
When its mass is set to 0.0 (the default value), the object remains fixed in
space during the simulation, although other objects will be able to collide
with it. For example, you could use a fixed rigid body to create a slope for
other objects to roll down. Other values allow the object to move during the
simulation, depending on other circumstances. A valid value for Mass is greater
than or equal to 0.0.
Friction The coefficient of friction for the object’s surface. This affects how
smoothly the rigid body moves relative to surfaces it’s in contact with. The
friction values for both objects combine to produce a coefficient for the
interaction. To achieve realistic results, use values between 0.0 and 1.0.
However, values up to 5.0 are accepted.
Elasticity This value governs the effect collisions have on the velocities of the
rigid body; in other words, how "bouncy" the object is. Like Friction, this is a
pair-wise coefficient: When two objects collide, their elasticity values combine
to produce a coefficient for the interaction. To achieve realistic results, use
values between 0.0 and 1.0. However, values up to 5.0 are accepted.
Inactive When on, the rigid body starts the simulation in an inactive state.
This means it requires interaction with another object or system, or the mouse,
3912 | Chapter 16 reactor