6.14.2 The Simplest Possible Particle Animation

Next we create an animation without any force fields. The question is, how to generate motions if there are no force field methods present? The answer is: we define the velocity attribute for particles manually.

1. Create a sphere (a particle).

2. Select the sphere and select the function Modify/Properties/Velocity.

This function allows you to define a line which represents the velocity vector of the particle. In other words, the particle will move that much in one second.

3. Create a PROCESSOR method.

4. Play the animation, and the particle moves.

Now, double the value of the Seconds field of the animation window. Play the animation again and the particle will move twice as far, in other words, twice as fast.

You can also modify the velocity attribute by selecting the particle and selecting the function Modify/Properties/TAGs. There should be a tag WEL associated with the particle describing its velocity. If it does not exist, the particle's velocity is zero (in other words, the particle is static).

Now, select the sphere and the function Modify/Properties/Spin. This function allows you to define three values in radians, representing three component spins. The value 3.14 makes the particle rotate 180 degrees around the corresponding axis in one second. Note that the rotation is defined in "object space". This means that if you rotate an object using, for example, the Modify/Linear/Rotate function, the spin axes are also rotated accordingly.

Define some spin values and play the animation. Now your sphere moves and rotates.