Applying to Real-World Applications - Essentials of Interactive Computer Graphics - page 140

• WorkPane . The view component displays the details of the slide that is cur-
rently being edited; the controller supports selecting and editing the content
of this slide.

• StylePane . The view component displays the layout design of the slide
that is currently being edited; the controller supports selecting and defining
a new layout design for this slide.

• NotesPane . The view component displays the notes that the user has cre-
ated for the slide that is currently being edited; the controller supports edit-
ing of this notes.

As is the case with most modern interactive applications, PowerPoint defines an
application timer event to support user-defined animations (e.g., animated se-
quences between slide transitions). The coherency of the four view/controller
pairs can be maintained during the servicing of this application timer event. For
example, the user works with the StylePane to change the layout of the current
slide in the TheModel component. In the meantime, before servicing the next
timer event, OverviewPane and WorkPane are not aware of the changes and dis-
play an out-of-date design for the current slide. During the servicing of the timer
event, the MainUIWindow forces all view/controller pairs to poll TheModel and
refresh their contents. As discussed in Section 5.4, because the timer events are
typically triggered more than 30 times in a second, the user is not able to detect
the brief out-of-date display and observes a consistent display at all times. In this
way, the four view/controller pairs only need to keep a reference to the TheModel
component and do not need to have any knowledge of each other. Thus, it is
straightforward to insert and delete view/controller pairs into/from the applica-
tion.

6.2 Maya

We now apply our knowledge in analyzing and understanding Maya, 2 an interac-
tive 3D modeling/animation/rendering system. The left side of Figure 6.2 shows a
screenshot of Maya in a simple 3D content creation session. As in the case of Fig-
ure 6.1, the right side of Figure 6.2 shows how we can apply the implementation
framework to gain insights into the Maya application. Once again, we see that
the MainUIWindow is the GUI window of the entire application containing GUI
elements that affect/echo the entire application state, the TheModel component,
and all the view/controller pairs.

2 Maya is a registered trademark of Autodesk.