Programming With QuickTime VR

Elements of the QuickTime VR Movie Controller

The QuickTime VR movie controller provides control elements for zooming in and out and several other navigational controls. Figure 3-1 shows the elements supported by the QuickTime VR movie controller component.

Figure 1 The QuickTime VR movie controller

The user can navigate in a movie by holding the mouse button down and dragging inside the picture. The user can also use the controller bar to perform several other operations. The controller bar contains the following controls:

A go-back button. This control allows the user to return to the previous node. Clicking this button restores the previous static pan angle, tilt angle, and field of view. This button is enabled only for multinode movies.
A zoom-out button. This control allows the user to zoom out. Holding down the mouse button while the cursor is over this control causes the field of view of the displayed node to increase, thereby making the object or panorama appear to move away from the viewer.
A zoom-in button. This control allows the user to zoom in. Holding down the mouse button while the cursor is over this control causes the field of view of the displayed node to decrease, thereby making the object or panorama appear to move toward the viewer.
A hot spot display button. This control allows the user to highlight the visible hot spots. Holding down the mouse button while the cursor is over this control causes any hot spots in the currently visible portion of the panorama or object to be highlighted (a border is drawn around each hot spot, and the enclosed region is filled in a distinctive color). Releasing the mouse button restores the image to its unhighlighted state. Double-clicking the mouse button causes the hot spot display to latch in the on state so that the hot spots remain displayed during manipulation of the VR movie. In that state, a single mouse click turns the hot spot display off. This button is disabled for movies that do not have hot spots.
A translate mode button. This control allows the user to enable or disable translate mode. When translate mode is enabled, dragging the mouse causes an object to be translated instead of panned or tilted. This control is enabled only for object nodes.

In addition to these buttons, the controller bar also contains a label display area in which helpful information is displayed. For instance, when the cursor is over one of the buttons, the button's name appears in the label display area. Similarly, when the cursor is over a hot spot, the hot spot's name (if it has one) appears in the label display area.

You can programmatically change which of these buttons are displayed by issuing the appropriate movie controller actions; see "Movie Control Flags" for details. In addition, you can hide the controller bar entirely; see "Hiding and Showing the Controller Bar" for details.