Jitter

The Effects->Jitter command in the Motion module allows you to apply random motion to an object. Compare this to the Effects->ShapeJitter and Effects->HrcShapeJitter effects in which you apply random motion to the control points of object or objects in hierarchies.

You can define the magnitude of the x, y, and z components for scaling, rotation, and translation, as well as a frequency parameter that determines how jittery the motion is: slow and languorous like a feather falling to the ground, or fast and jerky like a molecule. All parameters can be animated.

Procedure

1. Create a model.
2. Choose the Effects->Jitter command in the Motion module.
   
   The Jitter dialogue box is displayed.
   
   
3. Set the parameters as desired.

The effect icon appears indicating that the effect is active.

Note:

The location and shape of the icon do not affect the result.
Also, as with all Motion effects, the icon can be animated and the parameters set can be further edited or animated by selecting the icon and choosing the Effects->Edit Parameters command in the Motion module.

Parameters

Frame Start and End

Allows you to set the start and end frames for the effect.

Tension

Sets the tension for the curve interpolation used in the calculations.

Frame Rate

For the motion timing to be correct, this option must be set to the same frame rate being used in SOFTIMAGE 3D, usually 30.0 or 24.0 frames per second.

Scale, Rotate, and Translate

• Seed: Specifies a seed value for the random number generator. Use different values to create different random patterns of motion.
• x, y, and z: Sets the relative magnitude for jittering in the x, y, and z axes.
• Frequency: Sets the relative frequency of the effect. A value of 1 sets a very high frequency, while smaller values (down to 0.0001) reduce the frequency to create a smoother effect.
• Cumulative: Accumulates jittering effects on the model.
• FCurve Present: This option must be selected if the object already has an function curve for scale, rotate, or translate; otherwise, the motion generated is incorrect.

Next, Previous, Delete, Key, and Frame

Next advances to the next keyframe, Previous goes back to the previous keyframe, Delete removes a keyframe, and Key sets a keyframe at the frame you specify in the Frame text box. These controls are available only after you have set the initial parameters in the dialogue box and clicked Ok. To return to the dialogue box and edit keyframes for the effect, select the effect icon and choose the Effects->Edit Parameters command in the Motion module.

Last updated 02-apr-1998