Made GameList use quicksort instead of selection sort, resulting in approx.

12-15X speedup on large folders.


git-svn-id: svn://svn.code.sf.net/p/stella/code/trunk@1032 8b62c5a3-ac7e-4cc8-8f21-d9a121418aba

stella/src/gui/GameList.cxx

@@ -13,7 +13,7 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: GameList.cxx,v 1.8 2006-03-09 00:29:52 stephena Exp $
+// $Id: GameList.cxx,v 1.9 2006-03-10 00:29:46 stephena Exp $
 //
 //   Based on code from KStella - Stella frontend
 //   Copyright (C) 2003-2005 Stephen Anthony
@@ -33,44 +33,97 @@ GameList::GameList()
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 GameList::~GameList()
 {
-  myArray.clear();
+  clear();
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void GameList::appendGame(const string& name, const string& path,
                           const string& note, bool isDir)
 {
-  Entry g;
-  g._name  = name;
-  g._path  = path;
-  g._note  = note;
-  g._isdir = isDir;
+  Entry* g = new Entry;
+  g->_name  = name;
+  g->_path  = path;
+  g->_note  = note;
+  g->_isdir = isDir;
 
   myArray.push_back(g);
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void GameList::clear()
+{
+  for(unsigned int i = 0; i < myArray.size(); ++i)
+    delete myArray[i];
+
+  myArray.clear();
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void GameList::sortByName()
 {
   if(myArray.size() <= 1)
     return;
 
-  // Simple selection sort
-  for (unsigned int i = 0; i < myArray.size()-1; i++)
-  {
-    unsigned int min = i;
-    for (unsigned int j = i+1; j < myArray.size(); j++)
-    {
-      // TODO - add option for this
-      string atJ   = myArray[j]._name;
-      string atMin = myArray[min]._name;
-      transform(atJ.begin(), atJ.end(), atJ.begin(), (int(*)(int)) toupper);
-      transform(atMin.begin(), atMin.end(), atMin.begin(), (int(*)(int)) toupper);
-
-      if (atJ < atMin)
-        min = j;
-    }
-    if (min != i)
-      SWAP(myArray[min], myArray[i]);
-  }
+  QuickSort(myArray, 0, myArray.size()-1);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void GameList::QuickSort(EntryList& a, int left, int right)
+{
+  int l_hold = left;
+  int r_hold = right;
+  Entry* pivot_entry = a[left];
+
+  while (left < right)
+  {
+    while ((compare(a[right]->_name, pivot_entry->_name) >= 0) && (left < right))
+      right--;
+    if (left != right)
+    {
+      a[left] = a[right];
+      left++;
+    }
+    while ((compare(a[left]->_name, pivot_entry->_name) <= 0) && (left < right))
+      left++;
+    if (left != right)
+    {
+      a[right] = a[left];
+      right--;
+    }
+  }
+
+  a[left] = pivot_entry;
+  int pivot = left;
+  left = l_hold;
+  right = r_hold;
+  if (left < pivot)
+    QuickSort(a, left, pivot-1);
+  if (right > pivot)
+    QuickSort(a, pivot+1, right);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+int GameList::compare(const string& s1, const string& s2)
+{
+  string::const_iterator it1=s1.begin();
+  string::const_iterator it2=s2.begin();
+
+  // Stop when either string's end has been reached
+  while( (it1 != s1.end()) && (it2 != s2.end()) ) 
+  { 
+    if(::toupper(*it1) != ::toupper(*it2)) // letters differ?
+      // return -1 to indicate smaller than, 1 otherwise
+      return (::toupper(*it1)  < ::toupper(*it2)) ? -1 : 1; 
+
+    // proceed to the next character in each string
+    ++it1;
+    ++it2;
+  }
+  size_t size1 = s1.size(), size2 = s2.size(); // cache lengths
+
+  // return -1,0 or 1 according to strings' lengths
+  if (size1 == size2) 
+    return 0;
+  else
+    return (size1 < size2) ? -1 : 1;
 }

stella/src/gui/GameList.hxx

@@ -13,7 +13,7 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: GameList.hxx,v 1.9 2006-03-09 00:29:52 stephena Exp $
+// $Id: GameList.hxx,v 1.10 2006-03-10 00:29:46 stephena Exp $
 //
 //   Based on code from KStella - Stella frontend
 //   Copyright (C) 2003-2005 Stephen Anthony
@@ -38,24 +38,32 @@ class GameList
       bool   _isdir;
     };
 
-    typedef Common::Array<Entry> EntryList;
+    typedef Common::Array<Entry*> EntryList;
     EntryList myArray;
 
   public:
     GameList();
     ~GameList();
 
-    inline const string& name(int i) { return myArray[i]._name; }
-    inline const string& path(int i) { return myArray[i]._path; }
-    inline const string& note(int i) { return myArray[i]._note; }
-    inline const bool isDir(int i)   { return myArray[i]._isdir; }
+    inline const string& name(int i)
+    { return i < (int)myArray.size() ? myArray[i]->_name : EmptyString; }
+    inline const string& path(int i)
+    { return i < (int)myArray.size() ? myArray[i]->_path : EmptyString; }
+    inline const string& note(int i)
+    { return i < (int)myArray.size() ? myArray[i]->_note : EmptyString; }
+    inline const bool isDir(int i)
+    { return i < (int)myArray.size() ? myArray[i]->_isdir: false; }
 
     inline int size() { return myArray.size(); }
+    void clear();
 
-    void clear() { myArray.clear(); }
     void appendGame(const string& name, const string& path, const string& note,
                     bool isDir = false);
     void sortByName();
+
+  private:
+    static void QuickSort(EntryList& list, int l, int r);
+    inline static int compare(const string& s1, const string& s2);
 };
 
 #endif

stella/src/gui/LauncherDialog.cxx

@@ -13,7 +13,7 @@
 // See the file "license" for information on usage and redistribution of
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //
-// $Id: LauncherDialog.cxx,v 1.45 2006-03-09 17:04:01 stephena Exp $
+// $Id: LauncherDialog.cxx,v 1.46 2006-03-10 00:29:46 stephena Exp $
 //
 //   Based on code from ScummVM - Scumm Interpreter
 //   Copyright (C) 2002-2004 The ScummVM project
@@ -279,8 +279,6 @@ void LauncherDialog::updateListing(bool fullReload)
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void LauncherDialog::loadDirListing()
 {
-cerr << "browse path = " << myCurrentDir << endl;
-
   FilesystemNode dir(myCurrentDir);
   FSList files = dir.listDir(FilesystemNode::kListAll);