Anim-curve
This samples demonstrates a different style of animation based on the dependency graph and linked node attributes. This is an implementation of the system used in 3D animation tools such as Maya.
In this sample we create a MOAIAnimCurve and configure it with two key frames. The first key is at time 0 seconds and has a value of 0. The second key is at time 1.5 seconds and has a value of 360. As the curve is evaluated and time goes from 0 to 1.5 seconds, the value of the curve will go from 0 to 360.
The curve is a node and has the attributes ATTR_TIME and ATT_VALUE. ATTR_TIME is an input and ATTR_VALUE is an output. We can link the curve's ATTR_VALUE to the prop's ATTR_Z_ROT but nothing will happen. To animate the prop we need a timer.
MOAITimer is both a node and an action. Because it is an action it may be added to the action tree which will cause it to receive time=based updates every sim step. Because MOAITimer is also a node, it has attributes that may be linked to other nodes in the dependency graph.
MOAITimer exposes a single output attribute called ATTR_TIME. To animate the prop, we link the timer's ATTR_TIME output to the curve's ATTR_TIME input and the curve's ATTR_VALUE output to the prop's ATTR_Z_ROT:
MOAITimer.ATTR_TIME -> MOAIAnimCurve.ATTR_TIME MOAIAnimCurve.ATTR_VALUE -> MOAIProp.ATTR_Z_ROT
Calling start () on the timer action with no inputs adds the timer to the root of the action tree which causes it to begin receiving time based updates. Each update causes the timer to progress, which changes the value of its ATTR_TIME. This causes the curve's ATTR_VALUE to change which, finally, animates the prop.
This sample is just a demonstration of attributes, curves and the dependency graph. In production you will probably not want to do animation this way but instead use curves with MOAIAnim. See the anim-driver sample for more about MOAIAnim.