Technical Q&As

AMT_PE 13 - "Preloading" Media Objects in AMT (1-Aug-95)

Q Can I force AMT not to preload (into RAM) media for a screen until the user wants to enter that screen?

A Yes. In fact, this is the way AMT applications work by default. Whenever you change screens, all media on the old screen but not used on the new screen is unloaded. There is some state information about all objects on all screens kept in RAM at all times, but this size of information is negligible compared to the size of the media assets for a screen in all but the largest of projects.

Once the user goes to a screen, all WAV audio files are preloaded. QuickTime movies are opened but only read into RAM if you have chose "Preload" from the Media Properties dialog. The same goes for PICT files. If you specify many items to preload, it can take longer to go to the screen and your RAM requirements will increase. On the other hand, if you do not preload items, they may be slow to re-draw. (As a rule, always preload background PICTS, since these need frequent updating). By carefully choosing which items to preload and which not, you can balance screen load times and RAM requirements against performance issues.

Technical Q&As
Previous Question | Contents | Next Question