fix paths on overlapping layers

src/instance.rs

@@ -155,9 +155,9 @@ impl<'m> SearchInstance<'m> {
             root: from.0,
             interval: (Vec2::new(0.0, 0.0), Vec2::new(0.0, 0.0)),
             edge: (0, 0),
-            polygon_from: u32::MAX,
+            polygon_from: from.1,
             polygon_to: from.1,
-            previous_polygon_layer: to.1.layer(),
+            previous_polygon_layer: from.1.layer(),
             f: 0.0,
             g: 0.0,
         };
@@ -620,7 +620,7 @@ impl<'m> SearchInstance<'m> {
                             }
                             continue;
                         }
-                        let vertex = self.mesh.layers[node.polygon_to.layer() as usize]
+                        let vertex = self.mesh.layers[node.previous_polygon_layer as usize]
                             .vertices
                             .get(node.edge.0 as usize)
                             .unwrap();
@@ -645,7 +645,7 @@ impl<'m> SearchInstance<'m> {
                             }
                             continue;
                         }
-                        let vertex = self.mesh.layers[node.polygon_to.layer() as usize]
+                        let vertex = self.mesh.layers[node.previous_polygon_layer as usize]
                             .vertices
                             .get(node.edge.1 as usize)
                             .unwrap();

src/layers.rs

@@ -436,24 +436,34 @@ mod tests {
     }
 
     #[test]
-    fn take_long_way() {
+    fn shortcut_with_corner() {
         let mesh = mesh_overlapping_layers();
         for i in 7..15 {
             let from = Vec2::new(i as f32 / 10.0, 2.1);
             let to = Vec2::new(5.0 - i as f32 / 10.0, 0.9);
             let path = dbg!(mesh.path(from, to).unwrap());
-            assert_eq!(path.path, vec![vec2(2.0, 2.0), vec2(3.0, 1.0), to]);
+            match i {
+                7 => assert_eq!(path.path, vec![vec2(1.0, 2.0), to]),
+                _ if i < 11 => assert_eq!(path.path, vec![vec2(1.0, 2.0), vec2(4.0, 1.0), to]),
+                _ if i < 15 => assert_eq!(path.path, vec![vec2(2.0, 2.0), vec2(3.0, 1.0), to]),
+                _ => unreachable!(),
+            }
         }
     }
 
     #[test]
-    fn take_long_way_back() {
+    fn shortcut_with_corner_back() {
         let mesh = mesh_overlapping_layers();
         for i in 7..15 {
             let from = Vec2::new(5.0 - i as f32 / 10.0, 0.9);
             let to = Vec2::new(i as f32 / 10.0, 2.1);
             let path = dbg!(mesh.path(from, to).unwrap());
-            assert_eq!(path.path, vec![vec2(3.0, 1.0), vec2(2.0, 2.0), to]);
+            match i {
+                7 => assert_eq!(path.path, vec![vec2(4.0, 1.0), to]),
+                _ if i < 11 => assert_eq!(path.path, vec![vec2(4.0, 1.0), vec2(1.0, 2.0), to]),
+                _ if i < 15 => assert_eq!(path.path, vec![vec2(3.0, 1.0), vec2(2.0, 2.0), to]),
+                _ => unreachable!(),
+            }
         }
     }
 

src/lib.rs

@@ -285,7 +285,7 @@ impl Mesh {
             queue: BinaryHeap::new(),
             node_buffer: Vec::new(),
             root_history: HashMap::new(),
-            from: Vec2::ZERO,
+            from: node.root,
             to,
             polygon_to: self.get_point_location(to),
             mesh: self,