Programming with QuickTime VR

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QTVRSetFrameRate

You can use the QTVRSetFrameRate function to set the frame rate of an object node.

OSErr QTVRSetFrameRate (QTVRInstance qtvr, float rate);
qtvr
An instance of a QuickTime VR movie.
rate
The desired frame rate of the specified movie. A frame rate is a floating-point value in the range from -100.0 to +100.0. Positive values indicate forward rates, and negative values indicate reverse rates. Set this parameter to 0 to stop the movie.
function result
A result code.

DESCRIPTION

The QTVRSetFrameRate function sets the frame rate of the object node specified by the qtvr parameter to the rate specified by the rate parameter. This function is most useful when an object is being viewed with a looping animation. (The current view of the object may contain frames that are played in a loop, as specified by the file format.) You can use QTVRSetFrameRate to change the frame rate of the loop.

If the value specified in the rate parameter lies outside the valid range, QTVRSetFrameRate returns the result code constraintReachedErr and sets the frame rate to the nearest constraint.

SPECIAL CONSIDERATIONS

QTVRSetFrameRate is valid only for object nodes.

SEE ALSO

Use QTVRGetFrameRate (link) to get the frame rate of an object node.

© 1997 Apple Computer, Inc.

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