3D sketch: with 3D Sketch on, the Line, Spline and Point tools take points off the sketch plane, snapping to model vertices, edges and faces and to drawn 3D points (segments that stay on the plane are ordinary sketch lines); drawn 3D curves are wires with fit points (sketch.line3d, sketch.spline3d: centripetal Catmull-Rom, sketch.point3d), a clicked 3D point gets a move triad (drag along X/Y/Z or parallel to the sketch plane: sketch.move3d, joined ends move together), Delete removes it; sweep and pipe paths may mix 3D curves with sketch curves; control: ui.triad, ui.worldToScreen

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AS5Tn3xieewUSg3uxrMVdL

crates/engine/src/cmd/sketch_ux_tests.rs

@@ -564,3 +564,58 @@ fn constraints_and_dimensions_can_be_selected_and_deleted_together() {
     run(&mut s, "selection.delete", json!({"items": items}));
     assert!(sketch(&s).constraints.is_empty());
 }
+
+// ---------------------------------------------------------------------------------------------
+// 3D sketch
+
+#[test]
+fn three_d_curves_need_the_option_and_move_joined() {
+    let mut s = new_sketch();
+    assert!(s.execute("sketch.line3d", &json!({"points": [[0, 0, 0], [0, 0, 10]]})).is_err());
+    run(&mut s, "sketch.options", json!({"sketch_3d": true}));
+    let r = run(&mut s, "sketch.line3d", json!({"points": [[0, 0, 0], [0, 0, 10], [10, 0, 10]]}));
+    let ids = curve_ids(&r);
+    assert_eq!(ids.len(), 2);
+    run(&mut s, "sketch.point3d", json!({"point": [5, 5, 5]}));
+    let sp = run(&mut s, "sketch.spline3d", json!({"points": [[10, 0, 10], [15, 5, 12], [20, 0, 20]]}));
+    let sid = curve_ids(&sp)[0].clone();
+    let sk = sketch(&s);
+    let w = &sk.wires[sk.wire_index(&sid).expect("spline")];
+    assert!(w.pts.len() > 10);
+    assert!(w.pts.first().expect("p").dist(solvecraft_geom::Vec3::new(10.0, 0.0, 10.0)) < 1e-12);
+    assert!(w.pts.last().expect("p").dist(solvecraft_geom::Vec3::new(20.0, 0.0, 20.0)) < 1e-12);
+    // The shared corner moves for both lines (and the spline that starts there).
+    let r = run(&mut s, "sketch.move3d", json!({"wire": ids[1], "index": 1, "by": [0, 0, 5]}));
+    assert_eq!(r["moved"], 2);
+    let r = run(&mut s, "sketch.move3d", json!({"wire": ids[0], "index": 1, "to": [0, 3, 12]}));
+    assert_eq!(r["moved"], 2);
+    let sk = sketch(&s);
+    let fit = |id: &str| sk.wires[sk.wire_index(id).expect("w")].fit.clone();
+    assert_eq!(fit(&ids[0])[1], fit(&ids[1])[0]);
+    assert!(s.execute("sketch.move3d", &json!({"wire": "nope", "to": [0, 0, 0]})).is_err());
+    assert!(s.execute("sketch.line3d", &json!({"points": [[0, 0, 0], [0, 0, 0]]})).is_err());
+    assert!(s.execute("sketch.line3d", &json!({"points": [[0, 0, 0], [f64::NAN, 0, 0]]})).is_err());
+    // Deleting works like any sketch entity.
+    run(&mut s, "sketch.delete", json!({"entities": [sid]}));
+    assert!(sketch(&s).wire_index(&curve_ids(&sp)[0]).is_none());
+}
+
+#[test]
+fn pipe_and_sweep_follow_3d_sketch_curves() {
+    let mut s = Session::default();
+    run(&mut s, "SketchCreate", json!({"plane": "XY", "name": "Path"}));
+    run(&mut s, "sketch.options", json!({"sketch_3d": true}));
+    let r = run(&mut s, "sketch.line3d", json!({"points": [[0, 0, 0], [0, 0, 30], [20, 0, 30]]}));
+    let mut path = curve_ids(&r);
+    let sp = run(&mut s, "sketch.spline3d", json!({"points": [[20, 0, 30], [35, 10, 35], [50, 0, 50]]}));
+    path.extend(curve_ids(&sp));
+    run(&mut s, "SketchStop", json!({}));
+    let p = run(&mut s, "PrimitivePipe", json!({"path_sketch": "Path", "path": path, "diameter": 4}));
+    let si = run(&mut s, "document.inspect", json!({"measure": true}));
+    let body = si["bodies"].as_array().and_then(|b| b.first()).cloned().unwrap_or_default();
+    // The tube runs from the first line's start to the spline's end (radius 2 around them).
+    let (lo, hi) = (&body["bbox"]["min"], &body["bbox"]["max"]);
+    let near = |v: &Value, x: f64| (v.as_f64().unwrap_or(f64::NAN) - x).abs() < 0.5;
+    assert!(near(&lo[0], -2.0) && near(&lo[2], 0.0) && near(&hi[0], 52.0) && near(&hi[2], 50.0), "{p} {body}");
+    assert!(body["volume_mm3"].as_f64().unwrap_or(0.0) > 4.0 * std::f64::consts::PI * 50.0 * 0.95, "{p} {body}");
+}