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51 lines
1.7 KiB
Text
51 lines
1.7 KiB
Text
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Mapping Timeline position to Track position
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TrackObject/TimelineObject basic properties (hereafter position):
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start
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duration
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in-point
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priority
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Use Cases:
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A TimelineObject can be tracking one or many TrackObject(s).
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When the TimelineObject position is modified we might need
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to cascade those changes to the controlled TrackObject(s) if those
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TrackObject(s) are 'locked' to the TimelineObject.
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If we modify the positions of a TrackObject that TrackObject is
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'locked' to the TimelineObject, we need to ensure all the other
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co-related TrackObject belong to the same TimelineObject are moved in
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the same way.
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A TrackObject can be temporarily 'unlocked' from its TimelineObject,
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so as to move it independently, and then 'locked' back to it. This
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can allow moves, like shifting audio trackobject in relation to the
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video trackobject (to fix sync issues) and then 'lock' them back so
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as to be able to move them as one entity thereafter.
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When adding TimelineOverlay(s) or TimelineEffect(s) on a
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TimelineObject, we need to ensure the TrackObject(s) that those extra
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effects will create can be added with specific priority offsets, in
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such a way that they always end up "on top" of the TimelineObject's
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existing tracked TrackObject(s).
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When a controlled TrackObject is being moved when 'unlocked', we need
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to make sure the duration/height of the TimelineObject is updated
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accordingly. Ex : moving a TrackObject down by one priority should
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increase the TimelineObject "heigh" property by 1.
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Main Problem:
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There needs to be a mapping between the TimelineObject basic
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properties and its controlled TrackObject(s) position.
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Design:
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TBD
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