QuickTime 4 Reference

Using Path Tween Components

The following sections describe how to use a variety of path tween components. All path tween operations have as input a QuickTime vector data stream for a path. (For information about QuickTime vectors, see Chapter 24, "QuickTime Vectors." ) Path tweeners interpret their time input in one of these ways:

As a percentage of path's length. For these types, either a point on the path or a MatrixRecord data structure is returned.
As a function. One operation returns the y value of the point on the path with a given x value, and the other returns the x value of the point on the path with a given y value.

If the kTweenReturnDelta flag (in an optional kTweenFlags atom in the kTweenEntry atom) is set, a path tween returns the change in value from the last time it was invoked. If the flag is not set, or if the component has not previously been invoked, the component returns the normal result for the tween.

Using Path Tween Components

CreateSampleVectorData Utility

CreateSamplePathTweenContainer Utility

Using a `kTweenTypePathToMatrixTranslation` Tween Component

Using a `kTweenTypePathToFixedPoint` Tween Component

Using a `kTweenTypePathToMatrixRotation` Tween Component

Using a `kTweenTypePathToMatrixTranslationAndRotation` Tween Component

Using a `kTweenTypePathXtoY` Tween Component

Using a `kTweenTypePathYtoX` Tween Component