Split crates

1 files changed, 117 insertions, 0 deletions

diff --git a/library/src/layout/transform.rs b/library/src/layout/transform.rs
new file mode 100644
index 00000000..4e0b8ac2
--- /dev/null
+++ b/library/src/layout/transform.rs
@@ -0,0 +1,117 @@
+use typst::geom::Transform;
+
+use crate::prelude::*;
+
+/// Move content without affecting layout.
+#[derive(Debug, Hash)]
+pub struct MoveNode {
+    /// The offset by which to move the content.
+    pub delta: Axes<Rel<Length>>,
+    /// The content that should be moved.
+    pub child: Content,
+}
+
+#[node(LayoutInline)]
+impl MoveNode {
+    fn construct(_: &mut Vm, args: &mut Args) -> SourceResult<Content> {
+        let dx = args.named("dx")?.unwrap_or_default();
+        let dy = args.named("dy")?.unwrap_or_default();
+        Ok(Self {
+            delta: Axes::new(dx, dy),
+            child: args.expect("body")?,
+        }
+        .pack())
+    }
+}
+
+impl LayoutInline for MoveNode {
+    fn layout_inline(
+        &self,
+        world: Tracked<dyn World>,
+        regions: &Regions,
+        styles: StyleChain,
+    ) -> SourceResult<Vec<Frame>> {
+        let mut frames = self.child.layout_inline(world, regions, styles)?;
+
+        let delta = self.delta.resolve(styles);
+        for frame in &mut frames {
+            let delta = delta.zip(frame.size()).map(|(d, s)| d.relative_to(s));
+            frame.translate(delta.to_point());
+        }
+
+        Ok(frames)
+    }
+}
+
+/// Transform content without affecting layout.
+#[derive(Debug, Hash)]
+pub struct TransformNode<const T: TransformKind> {
+    /// Transformation to apply to the content.
+    pub transform: Transform,
+    /// The content that should be transformed.
+    pub child: Content,
+}
+
+/// Rotate content without affecting layout.
+pub type RotateNode = TransformNode<ROTATE>;
+
+/// Scale content without affecting layout.
+pub type ScaleNode = TransformNode<SCALE>;
+
+#[node(LayoutInline)]
+impl<const T: TransformKind> TransformNode<T> {
+    /// The origin of the transformation.
+    #[property(resolve)]
+    pub const ORIGIN: Axes<Option<GenAlign>> = Axes::default();
+
+    fn construct(_: &mut Vm, args: &mut Args) -> SourceResult<Content> {
+        let transform = match T {
+            ROTATE => {
+                let angle = args.named_or_find("angle")?.unwrap_or_default();
+                Transform::rotate(angle)
+            }
+            SCALE | _ => {
+                let all = args.find()?;
+                let sx = args.named("x")?.or(all).unwrap_or(Ratio::one());
+                let sy = args.named("y")?.or(all).unwrap_or(Ratio::one());
+                Transform::scale(sx, sy)
+            }
+        };
+
+        Ok(Self { transform, child: args.expect("body")? }.pack())
+    }
+}
+
+impl<const T: TransformKind> LayoutInline for TransformNode<T> {
+    fn layout_inline(
+        &self,
+        world: Tracked<dyn World>,
+        regions: &Regions,
+        styles: StyleChain,
+    ) -> SourceResult<Vec<Frame>> {
+        let origin = styles.get(Self::ORIGIN).unwrap_or(Align::CENTER_HORIZON);
+        let mut frames = self.child.layout_inline(world, regions, styles)?;
+
+        for frame in &mut frames {
+            let Axes { x, y } = origin.zip(frame.size()).map(|(o, s)| o.position(s));
+            let transform = Transform::translate(x, y)
+                .pre_concat(self.transform)
+                .pre_concat(Transform::translate(-x, -y));
+
+            frame.transform(transform);
+        }
+
+        Ok(frames)
+    }
+}
+
+/// Kinds of transformations.
+///
+/// The move transformation is handled separately.
+pub type TransformKind = usize;
+
+/// A rotational transformation.
+const ROTATE: TransformKind = 1;
+
+/// A scale transformation.
+const SCALE: TransformKind = 2;