Merge pull request #315 from theironchef/fix/pen-space-moves-anchor

Pen: holding Space while dragging out a point moves it

ROADMAP.md

@@ -109,7 +109,7 @@ grade by behaviour against `plan/illustrator/`, not by whether a menu item exist
   - **Cutting:** Eraser, Scissors, Knife, Mirror & Cut, Line Cut and Rectangle Cut (real geometry, compound paths keep their holes).
   - **Transform:** Rotate, Reflect, Scale, Shear (click or Alt-click snaps the reference point to anchors and centres), Reshape, Free Transform (free and perspective distort and shear, switched by the keys held during a handle drag).
   - **Live Corners:** drag a live rectangle's corner widgets (Selection or Direct Selection) to round all corners, with a radius readout. Corners stay circular when the rectangle is scaled unevenly or along its own sides when rotated (the radius keeps its size, or scales by the mean scale with Scale Corners on); only a shear distorts them.
-  - **Pen:** Alt pressed in the middle of dragging out an anchor splits its handles and keeps the curve already shaped into it (only the outgoing handle follows the pointer).
+  - **Pen:** Alt pressed in the middle of dragging out an anchor splits its handles and keeps the curve already shaped into it (only the outgoing handle follows the pointer); Space held while dragging out an anchor moves it, handles and all.
   - **Graphs:** Column, Stacked Column, Bar, Stacked Bar, Line, Area, Scatter, Pie and Radar graph tools with Graph Data and Graph Type.
   - **Other:** Eyedropper, Gradient annotator, Artboard, Measure, Type, Hand, Zoom, Rotate View.
   - **Editing type:** double-clicking type with a selection tool switches to the Type tool with the caret where it was clicked.

crates/tools/src/pen.rs

@@ -2,7 +2,8 @@
 //!
 //! Click adds a corner anchor; click-drag adds a smooth anchor with symmetric handles (Alt breaks
 //! them: the incoming handle stays where it was when Alt went down and only the outgoing one
-//! follows the pointer); Shift constrains to 45°. Clicking the first anchor closes the path.
+//! follows the pointer; Space held moves the anchor, handles and all); Shift constrains to 45°.
+//! Clicking the first anchor closes the path.
 //! Enter/Esc (or switching tools) ends the path. Clicking the end of a selected open path continues
 //! it. The rubber-band preview shows the next segment. On a selected blend's spine a click adds a
 //! point (on a point no key object sits on: deletes it).
@@ -21,6 +22,8 @@ pub struct PenTool {
     hover: Option<Point>,
     /// The incoming handle of the anchor being dragged out, as last previewed.
     in_h: Point,
+    /// The pointer at the last button-down or drag: Space held moves the anchor as far as it moves.
+    last: Point,
 }
 
 /// The open path the pen is extending: the single selected open path.
@@ -61,6 +64,7 @@ impl Tool for PenTool {
                 vec![]
             }
             PointerKind::Down => {
+                self.last = ev.pos;
                 if let Some((id, first, last, _)) = active {
                     if ev.mods.shift {
                         p = last + vectorcraft_geom::constrain_angle(p - last, 45.0);
@@ -91,7 +95,15 @@ impl Tool for PenTool {
                 vec![Action::Begin("Pen".into()), Action::Preview("path.create".into(), json!({"anchors": [{"x": p.x, "y": p.y}]}))]
             }
             PointerKind::Drag => {
-                let Some((a, closing)) = self.drag else { return vec![] };
+                let Some((mut a, closing)) = self.drag else { return vec![] };
+                // Space held moves the anchor being placed, handles and all.
+                if ev.mods.space && !closing {
+                    let d = ev.pos - self.last;
+                    a += d;
+                    self.in_h += d;
+                    self.drag = Some((a, closing));
+                }
+                self.last = ev.pos;
                 let mut out_h = ev.pos;
                 if ev.mods.shift {
                     out_h = a + vectorcraft_geom::constrain_angle(ev.pos - a, 45.0);
@@ -249,6 +261,49 @@ mod tests {
         assert_eq!(handles(t.pointer(&cx, &drag)), (json!([300.0, 440.0]), json!([340.0, 440.0])));
     }
 
+    #[test]
+    fn space_moves_the_anchor_being_placed() {
+        let (mut d, _) = doc_with_rect();
+        let space = Mods { space: true, ..Mods::default() };
+        // The first anchor of a new path.
+        let (s, p) = (Selection::default(), paint());
+        let cx0 = cx(&d, &s, &p);
+        let mut t = PenTool::default();
+        t.pointer(&cx0, &PointerEvent::new(PointerKind::Down, 400.0, 420.0));
+        t.pointer(&cx0, &PointerEvent::new(PointerKind::Drag, 450.0, 420.0));
+        let created = |acts: Vec<Action>| match acts.as_slice() {
+            [Action::Preview(c, v)] if c == "path.create" => v["anchors"][0].clone(),
+            other => panic!("not a create preview: {other:?}"),
+        };
+        let a = created(t.pointer(&cx0, &PointerEvent::new(PointerKind::Drag, 450.0, 380.0).with_mods(space)));
+        assert_eq!(a, json!({"x": 400.0, "y": 380.0, "out": [450.0, 380.0], "in": [350.0, 380.0]}), "moved, handles and all");
+        // Space released: the drag shapes the handles round the anchor's new place.
+        let a = created(t.pointer(&cx0, &PointerEvent::new(PointerKind::Drag, 460.0, 380.0)));
+        assert_eq!(a, json!({"x": 400.0, "y": 380.0, "out": [460.0, 380.0], "in": [340.0, 380.0]}));
+        // An anchor added to an open path, its handles broken by Alt: the kept incoming handle
+        // moves with it.
+        let l = d.layers[0].id;
+        let id = d.alloc_id();
+        let line = vectorcraft_geom::shapes::line(Point::new(10.0, 300.0), Point::new(60.0, 300.0));
+        d.insert(Some(l), 1, vectorcraft_doc::Node::path(id, line, vectorcraft_doc::Appearance::default_art())).unwrap();
+        let mut s = Selection::default();
+        s.set([id]);
+        let cx = cx(&d, &s, &p);
+        let mut t = PenTool { drawing: true, ..PenTool::default() };
+        let alt = Mods { alt: true, ..Mods::default() };
+        t.pointer(&cx, &PointerEvent::new(PointerKind::Down, 400.0, 420.0));
+        t.pointer(&cx, &PointerEvent::new(PointerKind::Drag, 450.0, 420.0));
+        t.pointer(&cx, &PointerEvent::new(PointerKind::Drag, 450.0, 470.0).with_mods(alt));
+        let acts = t.pointer(&cx, &PointerEvent::new(PointerKind::Drag, 450.0, 450.0).with_mods(Mods { space: true, ..alt }));
+        assert_eq!(
+            acts,
+            vec![Action::Preview(
+                "path.appendAnchor".into(),
+                json!({"id": id.0, "x": 400.0, "y": 400.0, "in": [350.0, 400.0], "out": [450.0, 450.0]})
+            )]
+        );
+    }
+
     #[test]
     fn clicking_a_selected_blend_spine_adds_a_point() {
         let (mut d, _) = doc_with_rect();