added free functions for haldedge/edge find and exist

src/polymesh/algorithms/properties.hh

@@ -47,6 +47,19 @@ bool is_triangle(face_handle f);
 /// returns true iff face is a quad
 bool is_quad(face_handle f);
 
+/// returns the edge between two vertices
+/// (returns invalid handle if edge not found)
+/// (O(valence) running time)
+edge_handle edge_between(vertex_handle v0, vertex_handle v1);
+
+/// returns the halfedge between two vertices
+/// (returns invalid handle if halfedge not found)
+/// (O(valence) running time)
+halfedge_handle halfedge_from_to(vertex_handle v_from, vertex_handle v_to);
+
+/// returns true iff there is an edge between v0 and v1
+bool are_adjacent(vertex_handle v0, vertex_handle v1);
+
 /// returns true iff all faces are triangles
 bool is_triangle_mesh(Mesh const& m);
 /// returns true iff all faces are quads
@@ -227,6 +240,30 @@ inline int valence(vertex_handle v) { return v.adjacent_vertices().size(); }
 inline bool is_triangle(face_handle f) { return f.halfedges().size() == 3; }
 inline bool is_quad(face_handle f) { return f.halfedges().size() == 4; }
 
+inline edge_handle edge_between(vertex_handle v0, vertex_handle v1)
+{
+    for (auto h : v0.outgoing_halfedges())
+        if (h.vertex_to() == v1)
+            return h.edge();
+    return {};
+}
+
+inline halfedge_handle halfedge_from_to(vertex_handle v_from, vertex_handle v_to)
+{
+    for (auto h : v_from.outgoing_halfedges())
+        if (h.vertex_to() == v_to)
+            return h;
+    return {};
+}
+
+inline bool are_adjacent(vertex_handle v0, vertex_handle v1)
+{
+    for (auto h : v0.outgoing_halfedges())
+        if (h.vertex_to() == v1)
+            return true;
+    return false;
+}
+
 inline bool is_triangle_mesh(Mesh const& m) { return m.faces().all(is_triangle); }
 inline bool is_quad_mesh(Mesh const& m) { return m.faces().all(is_quad); }
 

src/polymesh/ranges.hh

@@ -364,10 +364,10 @@ struct edge_collection : smart_collection<Mesh*, edge_tag, iterator>
 
     /// Returns the edge handle between two vertices (invalid if not found)
     /// O(valence) computation
-    edge_handle find(vertex_handle v_from, vertex_handle v_to) const;
+    [[deprecated("use pm::edge_between instead")]] edge_handle find(vertex_handle v_from, vertex_handle v_to) const;
     /// Returns true iff an edge exists between the vertices
     /// O(valence) computation
-    bool exists(vertex_handle v_from, vertex_handle v_to) const;
+    [[deprecated("use pm::are_adjacent instead")]] bool exists(vertex_handle v_from, vertex_handle v_to) const;
 
     /// Splits this edge in half by inserting a vertex (which is returned)
     /// Preserves face attributes
@@ -417,10 +417,10 @@ struct halfedge_collection : smart_collection<Mesh*, halfedge_tag, iterator>
 
     /// Returns the half-edge handle between two vertices (invalid if not found)
     /// O(valence) computation
-    halfedge_handle find(vertex_handle v_from, vertex_handle v_to) const;
+    [[deprecated("use pm::halfedge_from_to instead")]] halfedge_handle find(vertex_handle v_from, vertex_handle v_to) const;
     /// Returns true iff an edge exists between the vertices
     /// O(valence) computation
-    bool exists(vertex_handle v_from, vertex_handle v_to) const;
+    [[deprecated("use pm::are_adjacent instead")]] bool exists(vertex_handle v_from, vertex_handle v_to) const;
 
     /// Collapsed the given half-edge by removing it, keeping the to_vertex, and creating new triangles
     /// Preserves half-edge properties but not face or vertex ones