Page 1052 - Kitab3DsMax

Part X: Dynamic Animation
wings in concert. Selecting the Birth option instead starts them flapping their wings when they are born,
and selecting Random offsets each instance differently.
For materials, the Time and Distance values determine the number of frames or the distance traveled before
a particle is completely mapped. You can apply materials to the icon that appears when the particle system
is created. The Get Material From button lets you select the object from which to get the material. The
options include the icon and the Instanced Geometry.
Rotation and Collision rollout
In the Rotation and Collision rollout is an option to enable interparticle collisions. This option causes
objects to bounce away from one another when their object boundaries overlap.
The Rotation and Collision rollout, shown in Figure 41.10, contains several controls to alter the rotation of
individual particles. The Spin Time is the number of frames required to rotate a full revolution. The Phase
value is the initial rotation of the particle. You can vary both of these values with Variation values.
Note
The Rotation and Collision rollout options also can increase the rendering time of a scene. n
FIGURE 41.10
The Rotation and Collision rollout options can control how objects collide with one another.

You also can set the axis about which the particles rotate. Options include Random, Direction of Travel/MBlur,
and User Defined. The Stretch value under the Direction of Travel option causes the object to elongate in the
direction of travel. The User Defined option lets you specify the degrees of rotation about each axis.
Interparticle collisions are computationally intensive and can easily be enabled or disabled with the Enable
option. You also can set how often the collisions are calculated. The Bounce value determines the speed of

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