allow custom start for vih_range and voh_range

src/OpenMesh/Core/Mesh/CirculatorsT.hh

@@ -60,6 +60,9 @@
 //== NAMESPACES ===============================================================
 
 namespace OpenMesh {
+
+template <typename> class CirculatorRange;
+
 namespace Iterators {
 
 template<class Mesh, class CenterEntityHandle, bool CW>
@@ -192,6 +195,8 @@ class GenericCirculatorBaseT {
         typedef const Mesh* mesh_ptr;
         typedef const Mesh& mesh_ref;
 
+    template <typename> friend class OpenMesh::CirculatorRange;
+
     public:
         GenericCirculatorBaseT() : mesh_(0), lap_counter_(0) {}
 
@@ -267,16 +272,18 @@ class GenericCirculatorT : protected GenericCirculatorBaseT<typename GenericCirc
         typedef typename GenericCirculatorBaseT<Mesh>::mesh_ref mesh_ref;
         typedef GenericCirculator_ValueHandleFnsT<Mesh, CenterEntityHandle, value_type, CW> GenericCirculator_ValueHandleFns;
 
+        template <typename> friend class OpenMesh::CirculatorRange;
+
     public:
         GenericCirculatorT() {}
         GenericCirculatorT(mesh_ref mesh, CenterEntityHandle start, bool end = false) :
-            GenericCirculatorBaseT<Mesh>(mesh, mesh.halfedge_handle(start), end) {
+            GenericCirculatorBaseT<Mesh>(mesh, mesh.halfedge_handle(start), end)
-
+        {
             GenericCirculator_ValueHandleFns::init(this->mesh_, this->heh_, this->start_, this->lap_counter_);
         }
         GenericCirculatorT(mesh_ref mesh, typename Mesh::HalfedgeHandle heh, bool end = false) :
-            GenericCirculatorBaseT<Mesh>(mesh, heh, end) {
+            GenericCirculatorBaseT<Mesh>(mesh, heh, end)
-
+        {
             GenericCirculator_ValueHandleFns::init(this->mesh_, this->heh_, this->start_, this->lap_counter_);
         }
         GenericCirculatorT(const GenericCirculatorT &rhs) : GenericCirculatorBaseT<Mesh>(rhs) {}
@@ -440,6 +447,8 @@ class GenericCirculatorT_DEPRECATED : protected GenericCirculatorBaseT<typename
         typedef typename GenericCirculatorBaseT<Mesh>::mesh_ref mesh_ref;
         typedef GenericCirculator_ValueHandleFnsT_DEPRECATED<Mesh, CenterEntityHandle, value_type> GenericCirculator_ValueHandleFns;
 
+        template <typename> friend class OpenMesh::CirculatorRange;
+
     public:
         GenericCirculatorT_DEPRECATED() {}
         GenericCirculatorT_DEPRECATED(mesh_ref mesh, CenterEntityHandle start, bool end = false) :

src/OpenMesh/Core/Mesh/PolyConnectivity.hh

@@ -98,8 +98,10 @@ struct CirculatorRangeTraitT
   using ITER_TYPE = ITER_T;
   using CENTER_ENTITY_TYPE = CENTER_ENTITY_T;
   using TO_ENTITYE_TYPE = TO_ENTITY_T;
-  static ITER_TYPE begin(const CONTAINER_TYPE& _container, CENTER_ENTITY_TYPE _ce) { return (_container.*begin_fn)(_ce); }
+  static ITER_TYPE begin(const CONTAINER_TYPE& _container, CENTER_ENTITY_TYPE _ce)   { return (_container.*begin_fn)(_ce); }
-  static ITER_TYPE end(const CONTAINER_TYPE& _container, CENTER_ENTITY_TYPE _ce)   { return (_container.*end_fn)(_ce); }
+  static ITER_TYPE begin(const CONTAINER_TYPE& _container, HalfedgeHandle _heh, int) { return ITER_TYPE(_container, _heh); }
+  static ITER_TYPE end(const CONTAINER_TYPE& _container, CENTER_ENTITY_TYPE _ce)     { return (_container.*end_fn)(_ce); }
+  static ITER_TYPE end(const CONTAINER_TYPE& _container, HalfedgeHandle _heh, int)   { return ITER_TYPE(_container, _heh, true); }
 };
 
 struct SmartVertexHandle;
@@ -1250,12 +1252,26 @@ public:
    */
   ConstVertexIHalfedgeRange vih_range(VertexHandle _vh) const;
 
+  /**
+   * @return The incoming halfedges incident to the specified vertex
+   * as a range object suitable for C++11 range based for loops.
+   * Like vih_range(VertexHandle _heh.to()) but starts iteration at _heh
+   */
+  ConstVertexIHalfedgeRange vih_range(HalfedgeHandle _heh) const;
+
   /**
    * @return The outgoing halfedges incident to the specified vertex
    * as a range object suitable for C++11 range based for loops.
    */
   ConstVertexOHalfedgeRange voh_range(VertexHandle _vh) const;
 
+  /**
+   * @return The outgoing halfedges incident to the specified vertex
+   * as a range object suitable for C++11 range based for loops.
+   * Like voh_range(VertexHandle _heh.from()) but starts iteration at _heh
+   */
+  ConstVertexOHalfedgeRange voh_range(HalfedgeHandle _heh) const;
+
   /**
    * @return The edges incident to the specified vertex
    * as a range object suitable for C++11 range based for loops.

src/OpenMesh/Core/Mesh/PolyConnectivity_inline_impl.hh

@@ -43,6 +43,7 @@
 #error Do not include this directly, include instead PolyConnectivity.hh
 #endif // OPENMESH_POLYCONNECTIVITY_INTERFACE_INCLUDE
 
+#include <OpenMesh/Core/Mesh/PolyConnectivity.hh> // To help some IDEs
 #include <OpenMesh/Core/Mesh/IteratorsT.hh>
 #include <OpenMesh/Core/Mesh/CirculatorsT.hh>
 
@@ -99,13 +100,23 @@ class CirculatorRange : public SmartRangeT<CirculatorRange<CirculatorRangeTraitT
         CirculatorRange(
                 const CONTAINER_TYPE &container,
                 CENTER_ENTITY_TYPE center) :
-            container_(container), center_(center) {}
+            container_(container), heh_()
-        ITER_TYPE begin() const { return CirculatorRangeTraitT::begin(container_, center_); }
+        {
-        ITER_TYPE end() const { return CirculatorRangeTraitT::end(container_, center_); }
+          auto it = CirculatorRangeTraitT::begin(container_, center);
+          heh_ = it.heh_;
+        }
+
+        CirculatorRange(
+                const CONTAINER_TYPE &container,
+                HalfedgeHandle heh, int) :
+            container_(container), heh_(heh) {}
+
+        ITER_TYPE begin() const { return CirculatorRangeTraitT::begin(container_, heh_, 1); }
+        ITER_TYPE end()   const { return CirculatorRangeTraitT::end(container_, heh_, 1); }
 
     private:
         const CONTAINER_TYPE &container_;
-        CENTER_ENTITY_TYPE center_;
+        HalfedgeHandle heh_;
 };
 
 
@@ -136,10 +147,18 @@ inline PolyConnectivity::ConstVertexIHalfedgeRange PolyConnectivity::vih_range(V
     return ConstVertexIHalfedgeRange(*this, _vh);
 }
 
+inline PolyConnectivity::ConstVertexIHalfedgeRange PolyConnectivity::vih_range(HalfedgeHandle _heh) const {
+    return ConstVertexIHalfedgeRange(*this, opposite_halfedge_handle(_heh), 1);
+}
+
 inline PolyConnectivity::ConstVertexOHalfedgeRange PolyConnectivity::voh_range(VertexHandle _vh) const {
     return ConstVertexOHalfedgeRange(*this, _vh);
 }
 
+inline PolyConnectivity::ConstVertexOHalfedgeRange PolyConnectivity::voh_range(HalfedgeHandle _heh) const {
+    return ConstVertexOHalfedgeRange(*this, _heh, 1);
+}
+
 inline PolyConnectivity::ConstVertexEdgeRange PolyConnectivity::ve_range(VertexHandle _vh) const {
     return ConstVertexEdgeRange(*this, _vh);
 }