Function zng::font::unicode_bidi_sort

pub fn unicode_bidi_sort(
    base_direction: LayoutDirection,
    line: impl Iterator<Item = (TextSegmentKind, Level)>,
    idx_offset: usize,
    sort_map: &mut Vec<usize>,
)

Compute a map of segments in line to their final LTR display order.

The result is set in sort_map.