Switch PDF backend to `krilla` (#5420)

Co-authored-by: Laurenz <laurmaedje@gmail.com>

1 files changed, 94 insertions, 0 deletions

diff --git a/crates/typst-pdf/src/link.rs b/crates/typst-pdf/src/link.rs
new file mode 100644
index 00000000..64cb8f0a
--- /dev/null
+++ b/crates/typst-pdf/src/link.rs
@@ -0,0 +1,94 @@
+use krilla::action::{Action, LinkAction};
+use krilla::annotation::{LinkAnnotation, Target};
+use krilla::destination::XyzDestination;
+use krilla::geom::Rect;
+use typst_library::layout::{Abs, Point, Size};
+use typst_library::model::Destination;
+
+use crate::convert::{FrameContext, GlobalContext};
+use crate::util::{AbsExt, PointExt};
+
+pub(crate) fn handle_link(
+    fc: &mut FrameContext,
+    gc: &mut GlobalContext,
+    dest: &Destination,
+    size: Size,
+) {
+    let mut min_x = Abs::inf();
+    let mut min_y = Abs::inf();
+    let mut max_x = -Abs::inf();
+    let mut max_y = -Abs::inf();
+
+    let pos = Point::zero();
+
+    // Compute the bounding box of the transformed link.
+    for point in [
+        pos,
+        pos + Point::with_x(size.x),
+        pos + Point::with_y(size.y),
+        pos + size.to_point(),
+    ] {
+        let t = point.transform(fc.state().transform());
+        min_x.set_min(t.x);
+        min_y.set_min(t.y);
+        max_x.set_max(t.x);
+        max_y.set_max(t.y);
+    }
+
+    let x1 = min_x.to_f32();
+    let x2 = max_x.to_f32();
+    let y1 = min_y.to_f32();
+    let y2 = max_y.to_f32();
+
+    let rect = Rect::from_ltrb(x1, y1, x2, y2).unwrap();
+
+    // TODO: Support quad points.
+
+    let pos = match dest {
+        Destination::Url(u) => {
+            fc.push_annotation(
+                LinkAnnotation::new(
+                    rect,
+                    None,
+                    Target::Action(Action::Link(LinkAction::new(u.to_string()))),
+                )
+                .into(),
+            );
+            return;
+        }
+        Destination::Position(p) => *p,
+        Destination::Location(loc) => {
+            if let Some(nd) = gc.loc_to_names.get(loc) {
+                // If a named destination has been registered, it's already guaranteed to
+                // not point to an excluded page.
+                fc.push_annotation(
+                    LinkAnnotation::new(
+                        rect,
+                        None,
+                        Target::Destination(krilla::destination::Destination::Named(
+                            nd.clone(),
+                        )),
+                    )
+                    .into(),
+                );
+                return;
+            } else {
+                gc.document.introspector.position(*loc)
+            }
+        }
+    };
+
+    let page_index = pos.page.get() - 1;
+    if let Some(index) = gc.page_index_converter.pdf_page_index(page_index) {
+        fc.push_annotation(
+            LinkAnnotation::new(
+                rect,
+                None,
+                Target::Destination(krilla::destination::Destination::Xyz(
+                    XyzDestination::new(index, pos.point.to_krilla()),
+                )),
+            )
+            .into(),
+        );
+    }
+}