Chapter 2
Document Model Issues for Hypermedia
Presentation
spatial layout: can be specify in several ways
- define items position relative to the display window
- define coordinates of an item relative to another item
- for example, subtitles next to a video, if subtitles are defined
relative to the video then, subtitles would be in the same neighborhood
relative to the video.
- object moves as function of time
- window with predefined areas to play media items : channels
- authors can make changes to channels which then apply to all the item
in the channel, can change with windows ; channels can
move in time, item positions within channel can change within time
- channels can be used for high level presentation specifications,
these can be media dependent (font style and size) or independent
(background color). This makes it easier to do global
changes. This high level specification can be used as a default and can be
overridden by specific layout specifications from individual media items