Game Development Reference
In-Depth Information
FixedUpdate()
The
FixedUpdate()
function is called every fixed framerate frame (or every constant
time), if the
MonoBehaviour
class is enabled.
Note
The difference between
FixedUpdate()
and
Update()
is that the
Update()
func-
tion is called every frame. On the other hand,
FixedUpdate()
is called every fixed
framerate frame. This depends on the
Fixed Timestep
value that we have set up. This will
result in stable physics calculations for all machines. For more information, visit the fol-
lowing link:
FixedUpdate()
should be used instead of
Update()
when dealing with physics cal-
culations. For example, when adding a force to a rigidbody, you have to apply the force to
every fixed frame inside
FixedUpdate()
instead of every frame inside
Update()
, be-
cause the physics simulation is carried out in discrete timesteps. The
FixedUpdate()
function is called immediately before each step. An example of
FixedUpdate()
is as
follows:
// JavaScript user:
// Apply an upward force to the rigidbody every frame
function FixedUpdate () {
rigidBody.AddForce(Vector3.up);
}
// C# user:
// Apply an upward force to the rigidbody every frame
void FixedUpdate () {
rigidBody.AddForce(Vector3.up);
}
