Merge pull request #1054 from hannobraun/sweep

Fix dodgy assumption in edge sweeping code
hannobraun · Sep 8, 2022 · d09ab54 · d09ab54
2 parents 72fc56f + 6d410f4
commit d09ab54
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Showing 2 changed files with 22 additions and 16 deletions.
diff --git a/crates/fj-kernel/src/algorithms/sweep/edge.rs b/crates/fj-kernel/src/algorithms/sweep/edge.rs
@@ -186,7 +186,10 @@ fn create_non_continuous_side_face(
             let [_, prev_last] = edges[i].vertices().get_or_panic();
             let [next_first, _] = edges[j].vertices().get_or_panic();
 
-            if prev_last.global_form() != next_first.global_form() {
+            // Need to compare surface forms here, as the global forms might be
+            // coincident when sweeping circles, despite the vertices being
+            // different!
+            if prev_last.surface_form() != next_first.surface_form() {
                 edges[j] = edges[j].reverse();
             }
 

diff --git a/crates/fj-kernel/src/builder/edge.rs b/crates/fj-kernel/src/builder/edge.rs
@@ -20,22 +20,25 @@ impl EdgeBuilder {
 
     /// Create a circle from the given radius
     pub fn circle_from_radius(&self, radius: Scalar) -> Edge {
-        let curve_local = CurveKind::Circle(Circle::new(
-            Point::origin(),
-            Vector::from([radius, Scalar::ZERO]),
-            Vector::from([Scalar::ZERO, radius]),
-        ));
-        let curve_global =
-            GlobalCurve::from_kind(CurveKind::Circle(Circle::new(
+        let curve = {
+            let local = CurveKind::Circle(Circle::new(
                 Point::origin(),
-                Vector::from([radius, Scalar::ZERO, Scalar::ZERO]),
-                Vector::from([Scalar::ZERO, radius, Scalar::ZERO]),
-            )));
-
-        Edge::from_curve_and_vertices(
-            Curve::new(self.surface, curve_local, curve_global),
-            VerticesOfEdge::none(),
-        )
+                Vector::from([radius, Scalar::ZERO]),
+                Vector::from([Scalar::ZERO, radius]),
+            ));
+            let global =
+                GlobalCurve::from_kind(CurveKind::Circle(Circle::new(
+                    Point::origin(),
+                    Vector::from([radius, Scalar::ZERO, Scalar::ZERO]),
+                    Vector::from([Scalar::ZERO, radius, Scalar::ZERO]),
+                )));
+
+            Curve::new(self.surface, local, global)
+        };
+
+        let vertices = VerticesOfEdge::none();
+
+        Edge::from_curve_and_vertices(curve, vertices)
     }
 
     /// Create a line segment from two points