Clippy: assign operators in the path sweep, isocurve grid and centre of mass

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01AS5Tn3xieewUSg3uxrMVdL

crates/doc/src/project3d.rs

@@ -363,12 +363,12 @@ pub fn iso_grid(m: &Mesh, f: u32, p: Vec3, count: usize) -> Vec<Vec<Vec3>> {
     for dir in ["u", "v"] {
         // The family's cutting direction, from the curve through p.
         let Some(first) = iso_curve(m, f, p, dir).into_iter().next() else { continue };
-        let pts: Vec<Vec3> = first.iter().copied().collect();
+        let pts: Vec<Vec3> = first.to_vec();
         // Normal of the plane that curve lies in.
         let Some(c) = pts.first().copied() else { continue };
         let mut n = Vec3::ZERO;
         for w in pts.windows(2) {
-            n = n + (w[0] - c).cross(w[1] - c);
+            n += (w[0] - c).cross(w[1] - c);
         }
         let cut_n = match n.normalized() {
             Some(n) => n,

crates/engine/src/cmd/sketch_inspect.rs

@@ -313,7 +313,7 @@ fn center_of_mass(s: &mut Session, p: &Value) -> Result<Value> {
             continue;
         }
         vol += m.volume;
-        moment = moment + m.centroid * m.volume;
+        moment += m.centroid * m.volume;
         out.push(json!({"body": b.name, "center": [m.centroid.x, m.centroid.y, m.centroid.z], "volume": m.volume}));
     }
     if out.is_empty() {

crates/kernel/src/sweep_path.rs

@@ -117,7 +117,7 @@ fn stations(pts: &[Vec3], tangents: &[Vec3], mitre: &[Option<(Vec3, f64)>]) -> R
         let mut m = [col(Vec3::X), col(Vec3::Y), col(Vec3::Z)];
         if let Some(Some((b, s))) = mitre.get(i) {
             for c in &mut m {
-                *c = *c + *b * ((s - 1.0) * c.dot(*b));
+                *c += *b * ((s - 1.0) * c.dot(*b));
             }
         }
         out.push(Station { at: *pts.get(i).ok_or_else(|| KernelError::Invalid("sweep path".into()))?, m });