|
One of the most useful, powerful and easiest to understand features of Xpressionist is to link objects together. You can use any animated animation channel to drive other object channels in Xpressionist. The channels you use to drive other channels are called custom variables.
1. Use the objects from the last section.
2. Go to the Xpressionist channel tab and add the Z rotate channel of Cube and Cone to the channel list.
3. Go to the Xpressionist editor tab and type this expression:
Cone.Roll_Z = Cube.Roll_Z;
Now the Cone's Z rotation channel will receive the value of the custom variable Cube.Roll_Z. You can now grab the Cube and roll it around and the Cone will rotate exactly the same as the Cube. You can now animate the Cube with keyframes and its animation will be the same for the Cone object.
You can drive as many objects as you like with one custom variable. You can also do math operations with your custom variable to alter the behavior of the driven objects:
1. Duplicate the cone of the setup two times.
2. Rename the cones to Cone1, Cone2 and Cone3 (make sure the UberShape instances have the auto name checkbox disabled to ensure that the object names do not revert on you).
3. Move Cone2 to X = 4 and Cone3 to X = 6.
4. Add the Z rotation channel of Cone1 and Cone2 to Xpressionist and type this expression:
Cone1.Roll_Z = Cube.Roll_Z;
Cone2.Roll_Z = Cube.Roll_Z * 2;
Cone3.Roll_Z = Cube.Roll_Z * 3;
Now all three cones will be driven by the Cubes Z rotation. Cone 2 will rotate twice as fast and Cone 3 will rotate three times as fast as the Cube object.
With dependencies like this you can easily set up all kinds of mechanical gear. Imagine a gearbox; you can animate the first sprocket and all other sprockets will automatically rotate according to their expression setup in Xpressionist. You can also build complex rigs to control characters and all kinds of other stuff.
Summary
In this section, you learned that you:
- can drive animation channels with other animation channels in Xpressionist
|
