diff -r 89c329efa980 -r e48454f237ca ganeswidgets/inc/HgScrollBufferManager.h
--- a/ganeswidgets/inc/HgScrollBufferManager.h	Mon Apr 19 14:40:06 2010 +0300
+++ b/ganeswidgets/inc/HgScrollBufferManager.h	Mon May 03 13:32:54 2010 +0300
@@ -22,6 +22,41 @@
 #include <qobject>
 #include <QTimer>
 
+class UpdatePair
+{
+public:
+    UpdatePair(int start, int count);
+
+    int start() const;
+    int end() const;
+
+    bool adjacent(int start, int count) const;
+    bool contains(const UpdatePair &other) const;
+    void extend(int start, int count);
+    void subtract(int start, int count);
+
+    void shiftRight(int count);
+    void shiftLeft(int count);
+
+    bool operator== (const UpdatePair &other) const;
+    bool operator< (const UpdatePair &other) const;
+
+private:
+    int mStart;
+    int mCount;
+};
+
+class UpdateBuffer : public QList<UpdatePair>
+{
+public:
+    UpdateBuffer();
+
+    void add(int start, int count);
+    void remove(int start, int count);
+    void shiftRight(int startingFrom, int amount);
+    void shiftLeft(int startingFrom, int amount);
+};
+
 class HgScrollBufferManager: public QObject
     {
     Q_OBJECT
@@ -41,9 +76,11 @@
 
     bool positionInsideBuffer(int position);
 
-    void removeItems(int start, int end, int totalCount);
-    void addItems(int start, int end, int totalCount);
-    void moveItems(int start, int end, int target, int totalCount);
+    void addItems(int start, int count);
+    void removeItems(int start, int end);
+    void moveItems(int start, int end, int target);
+
+    void flushRequestBuffers();
 
     void currentBuffer(int& bufferStart, int& bufferEnd);
 
@@ -60,8 +97,14 @@
 
     void init();
     void asyncUpdate();
-    bool isInsideBuffer(int pos);
-    bool isInsideBuffer(int start, int end);
+
+    int changeBufferPosition(int newPos);
+
+    void simpleAddItems(int start, int end);
+    void simpleRemoveItems(int start, int end);
+
+    void appendRequestBuffer(int start, int end);
+    void appendReleaseBuffer(int start, int end);
 
 private:
 
@@ -79,6 +122,9 @@
     int mReleaseCount;
     QTimer mTimer;
 
+    UpdateBuffer mRequestBuffer;
+    UpdateBuffer mReleaseBuffer;
+
 private:
     Q_DISABLE_COPY(HgScrollBufferManager)
     };