Changeset 1011:5bd6c7671c9e in lemon-0.x for src/lemon/smart_graph.h

Timestamp:

11/20/04 11:19:06 (21 years ago)

Author:

Alpar Juttner

Branch:

default

Phase:

public

Convert:

svn:c9d7d8f5-90d6-0310-b91f-818b3a526b0e/lemon/trunk@1401

Message:

• snapshot-rollback functionarity added to ListGraph?
• The iterface of the snapshot-rollback functionarity in SmartGraph? has changed to be compatible with ListGraph::SnapShot?.

File:

• src/lemon/smart_graph.h (modified) (2 diffs)

src/lemon/smart_graph.h

@@ -261 +261 @@
     }
     
-    ///Internal data structure to store snapshots
-    
-    ///\ingroup graphs
-    ///\sa makeSnapShot()
-    ///\sa rollBack()
-    struct SnapShot 
-    {
-      unsigned int node_num;
-      unsigned int edge_num;
-    };
-    
-    ///Make a snapshot of the graph.
-
-    ///Make a snapshot of the graph.
-    ///
-    ///The newly added nodes and edges can be removed using the
-    ///rollBack() function.
-    ///
-    ///\return An stucture SnapShot describing the pesent state of the
-    ///graph.
-    ///\note After you rolled back to a state, you cannot roll "back" to
-    ///a later state, in other word you cannot add again the edges deleted
-    ///by rollBack().
-    ///\todo This function might be called saveState() or getState().
-    SnapShot makeSnapShot() 
-    {
-      SnapShot s;
-      s.node_num=nodes.size();
-      s.edge_num=edges.size();
-      return s;
-    }
-    
-    ///Undo the changes until a snapshot.
-
-    ///Undo the changes until a snapshot created by makeSnapShot().
-    ///
-    ///\param s an internal stucture given back by makeSnapShot()
-    ///\note After you rolled back to a state, you cannot "roll forward" to
-    ///a later state, in other word you cannot add again the edges deleted
-    ///by rollBack().
-    ///
-    ///\todo This function might be called undo().
-    
-    void rollBack(const SnapShot &s)
+    class SnapShot;
+    friend class SnapShot;
+
+  protected:
+    void restoreSnapShot(const SnapShot &s)
     {
       while(s.edge_num>edges.size()) {
@@ -317 +278 @@
         nodes.pop_back();
       }
-    }
+    }    
+
+  public:
+    ///Class to make a snapshot of the graph and to restrore to it later.
+
+    ///Class to make a snapshot of the graph and to restrore to it later.
+    ///
+    ///The newly added nodes and edges can be removed using the
+    ///restore() function.
+    ///\note After you restore a state, you cannot restore
+    ///a later state, in other word you cannot add again the edges deleted
+    ///by restore() using another SnapShot instance.
+    ///
+    ///\ingroup graphs
+    class SnapShot 
+    {
+      SmartGraph *g;
+    protected:
+      friend class SmartGraph;
+      unsigned int node_num;
+      unsigned int edge_num;
+    public:
+      ///Default constructur.
+      
+      ///Default constructur.
+      ///To actually make a snapshot you must call save().
+      ///
+      SnapShot() : g(0) {}
+      ///Constructor that immediately makes a snapshot
+      
+      ///This constructor immediately makes a snapshot of the graph.
+      ///\param _g The graph we make a snapshot of.
+      SnapShot(SmartGraph &_g) :g(&_g) {
+        node_num=g->nodes.size();
+        edge_num=g->edges.size();
+      }
+
+      ///Make a snapshot.
+
+      ///Make a snapshot of the graph.
+      ///
+      ///This function can be called more than once. In case of a repeated
+      ///call, the previous snapshot gets lost.
+      ///\param _g The graph we make the snapshot of.
+      void save(SmartGraph &_g) 
+      {
+        g=&_g;
+        node_num=g->nodes.size();
+        edge_num=g->edges.size();
+      }
+
+      ///Undo the changes until a snapshot.
+      
+      ///Undo the changes until a snapshot created by save().
+      ///
+      ///\param s an internal stucture given back by save()
+      ///\note After you restored a state, you cannot restore
+      ///a later state, in other word you cannot add again the edges deleted
+      ///by restore().
+      ///
+      ///\todo This function might be called undo().
+      
+      void restore()
+      {
+        g->restoreSnapShot(*this);
+      }
+    };
   };