Quicktime File Format (2012-08-14).pdf

Media Data Atom TypesURL Hot Spot AtomURL Hot Spot AtomNote VR Media is deprecated in the QuickTime file format. The information that follows is intendedto document existing content containing VR Media and should not be used for new development.The URL hot spot atom has an atom type of kQTVRHotSpotURLType ('url '). The URL hot spot atom containsa URL string for a particular Web location (for example, http://quicktimevr.apple.com). QuickTime VRautomatically links to this URL when the hot spot is clicked.Support for Wired ActionsNote VR Media is deprecated in the QuickTime file format. The information that follows is intendedto document existing content containing VR Media and should not be used for new development.Certain actions on a QuickTime VR movie can trigger wired actions if the appropriate event handler atomshave been added to the file. This section discusses what atoms must be included in the QuickTime VR file tosupport wired actions.As with sprite tracks, the presence of a certain atom in the media property atom container of the QTVR trackenables the handling of wired actions. This atom is of type kSpriteTrackPropertyHasActions, which hasa single Boolean value that must be set to true.When certain events occur and the appropriate event handler atom is found in the QTVR file, then that atomis passed to QuickTime to perform any actions specified in the atom. The event handler atoms themselvesmust be added to the node information atom container in the QTVR track. There are two types of event handlersfor QTVR nodes: global and hot spot specific. The currently supported global event handlers arekQTEventFrameLoaded and kQTEventIdle. The event handler atoms for these are located at the root levelof the node information atom container. A global event handler atom’s type is set to the event type and its IDis set to 1.Hot spot–specific event handler atoms are located in the specific hot spot atom as a sibling to the hot spotinfo atom. For these atoms, the atom type is always kQTEventType and the ID is the event type. Supportedhot spot–specific event types are kQTEventMouseClick, kQTEventMouseClickEnd,kQTEventMouseClickEndTriggerButton, and kQTEventMouseEnter, kQTEventMouseExit.The specific actions that cause these events to be generated are described as follows:2012-08-14 | © 2004, 2012 Apple Inc. All Rights Reserved.283