fn map_content_time(time: &SegmentTime, content_duration: f64) -> (f64, f64)Expand description
Map a cell-local time context into a container’s content coordinates.
The cell wrapping the container applies its own rate function; the content
position is content_duration · (local_secs / cell_duration), mirroring the
pure path’s content_secs = cursor · rate(alpha) mapping.