Transform: Align to Pixel Grid keeps an object's horizontal and vertical edges on the pixel grid

Squashed from #6169 onto main.

crates/doc/src/node/extras.rs

@@ -69,6 +69,9 @@ pub struct NodeExtras {
     /// As an envelope with margins in Edit Contents, the margins its strokes gave when Edit Contents
     /// began ([`crate::live::EnvelopeOptions::bounds_margin`]).
     pub envelope_edit_margin: Option<[f32; 4]>,
+    /// Transform panel › Align to Pixel Grid: the path's or compound path's horizontal and vertical
+    /// segments stay on the pixel grid when it is transformed.
+    pub pixel_aligned: bool,
 }
 
 /// No extras: what [`Node::extras`] gives for a node without any.
@@ -95,6 +98,7 @@ pub(super) static NO_EXTRAS: NodeExtras = NodeExtras {
     shape_mode: crate::ShapeMode::Add,
     symbol_overrides: Vec::new(),
     envelope_edit_margin: None,
+    pixel_aligned: false,
 };
 
 /// A node's [`NodeExtras`], if it has any ([`Node::extras`]). Extras that are all unset equal

crates/doc/src/node/tests.rs

@@ -22,6 +22,7 @@ fn extras_are_written_flat_in_order() {
         e.compound_shape = true;
         e.shape_mode = crate::ShapeMode::Exclude;
         e.envelope_edit_margin = Some([0.5, 0.5, 0.25, 0.25]);
+        e.pixel_aligned = true;
     }
     /// The top-level keys of a JSON object, in the order written.
     struct Keys(Vec<String>);
@@ -67,9 +68,11 @@ fn extras_are_written_flat_in_order() {
         "compound_shape",
         "shape_mode",
         "envelope_edit_margin",
+        "pixel_aligned",
     ];
     assert_eq!(keys, order);
     assert_eq!(v["shape_mode"], "exclude");
+    assert_eq!(v["pixel_aligned"], true);
     assert_eq!(serde_json::from_value::<Node>(v).unwrap(), n);
     let plain = Node::path(NodeId(9), shapes::rectangle(Rect::new(0.0, 0.0, 4.0, 2.0)), Appearance::default_art());
     let back: Node = serde_json::from_value(serde_json::to_value(&plain).unwrap()).unwrap();

crates/doc/src/node/wire.rs

@@ -54,6 +54,7 @@ impl Serialize for Node {
             is_default(&e.shape_mode),
             e.symbol_overrides.is_empty(),
             e.envelope_edit_margin.is_none(),
+            is_default(&e.pixel_aligned),
         ];
         let mut st = s.serialize_struct("Node", skips.iter().filter(|s| !**s).count())?;
         let mut skip = skips.into_iter();
@@ -96,6 +97,7 @@ impl Serialize for Node {
         field!("shape_mode", &e.shape_mode);
         field!("symbol_overrides", &e.symbol_overrides);
         field!("envelope_edit_margin", &e.envelope_edit_margin);
+        field!("pixel_aligned", &e.pixel_aligned);
         st.end()
     }
 }
@@ -236,6 +238,8 @@ pub(super) struct NodeWire {
     symbol_overrides: Vec<crate::SymbolOverride>,
     #[serde(default)]
     envelope_edit_margin: Option<[f32; 4]>,
+    #[serde(default)]
+    pixel_aligned: bool,
 }
 
 impl From<NodeWire> for Node {
@@ -263,6 +267,7 @@ impl From<NodeWire> for Node {
             shape_mode: w.shape_mode,
             symbol_overrides: w.symbol_overrides,
             envelope_edit_margin: w.envelope_edit_margin,
+            pixel_aligned: w.pixel_aligned,
         };
         Node {
             id: w.id,