diff options
| -rw-r--r-- | crates/typst-library/src/layout/grid/resolve.rs | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/crates/typst-library/src/layout/grid/resolve.rs b/crates/typst-library/src/layout/grid/resolve.rs index 42df8953..acb588e9 100644 --- a/crates/typst-library/src/layout/grid/resolve.rs +++ b/crates/typst-library/src/layout/grid/resolve.rs @@ -680,6 +680,10 @@ pub struct CellGrid<'a> { pub headers: Vec<Repeatable<Header>>, /// The repeatable footers of this grid. pub footers: Vec<Repeatable<Footer>>, + /// Footers sorted by order of when they start repeating, or should + /// otherwise be laid out for the first time (even if only once, for + /// non-repeating footers). + pub sorted_footers: Vec<Repeatable<Footer>>, /// Whether this grid has gutters. pub has_gutter: bool, } @@ -749,6 +753,9 @@ impl<'a> CellGrid<'a> { rows.pop(); } + let footers: Vec<Repeatable<Footer>> = footer.into_iter().collect(); + let sorted_footers = simulate_footer_repetition(&footers); + Self { cols, rows, @@ -2394,3 +2401,50 @@ fn skip_auto_index_through_fully_merged_rows( } } } + +/// Generates a vector where all footers are sorted ahead of time by the points +/// at which they start repeating. When a new footer is about to be laid out, +/// conflicting footers which come before it in this vector must stop +/// repeating. +fn simulate_footer_repetition( + footers: &[Repeatable<Footer>], +) -> Vec<&Repeatable<Footer>> { + if footers.len() <= 1 { + return footers.iter().collect(); + } + + let mut ordered_footers = Vec::with_capacity(footers.len()); + let mut repeating_footers: Vec<&Repeatable<Footer>> = vec![]; + + // Read footers in reverse, using the same algorithm as headers to + // determine when a footer starts and stops repeating, but going from grid + // end to start. When it stops repeating, that's when it will start + // repeating in proper layout (from start to end), whereas it starts + // repeating here when it should stop repeating in practice. So, + // effectively, repeated footer layout is the same as for headers, but + // reversed, which we take advantage of by doing it reversed and then + // reversing it all back later. + for footer in footers.iter().rev() { + // Keep only lower level footers. Assume sorted by increasing levels. + let stopped_repeating = repeating_footers + .drain(repeating_footers.partition_point(|f| f.level < footer.level)..); + + // If they stopped repeating here, that's when they will start + // repeating. We save them in reverse of the reverse order so they stay + // sorted by increasing levels when we reverse `ordered_footers` later. + ordered_footers.extend(stopped_repeating.rev()); + + if footer.repeated { + // Start repeating now. Vector stays sorted by increasing levels, + // as any higher-level footers stopped repeating now. + repeating_footers.push(footer); + } else { + // Immediately finishes repeating. + ordered_footers.push(footer); + } + } + + ordered_footers.reverse(); + + ordered_footers +} |