Merge pull request #6975 from JosJuice/qt-fast-gamelist

DolphinQt2: Show cached games before checking whether they exist on disk

Source/Core/DolphinQt2/GameList/GameListModel.cpp

@@ -18,8 +18,7 @@ const QSize GAMECUBE_BANNER_SIZE(96, 32);
 GameListModel::GameListModel(QObject* parent) : QAbstractTableModel(parent)
 {
   connect(&m_tracker, &GameTracker::GameLoaded, this, &GameListModel::UpdateGame);
-  connect(&m_tracker, &GameTracker::GameRemoved, this,
-          [this](const QString& path) { RemoveGame(path.toStdString()); });
+  connect(&m_tracker, &GameTracker::GameRemoved, this, &GameListModel::RemoveGame);
   connect(&Settings::Instance(), &Settings::PathAdded, &m_tracker, &GameTracker::AddDirectory);
   connect(&Settings::Instance(), &Settings::PathRemoved, &m_tracker, &GameTracker::RemoveDirectory);
   connect(&Settings::Instance(), &Settings::PathReloadRequested, &m_tracker,
@@ -28,6 +27,8 @@ GameListModel::GameListModel(QObject* parent) : QAbstractTableModel(parent)
   for (const QString& dir : Settings::Instance().GetPaths())
     m_tracker.AddDirectory(dir);
 
+  m_tracker.Start();
+
   connect(&Settings::Instance(), &Settings::ThemeChanged, [this] {
     // Tell the view to repaint. The signal 'dataChanged' also seems like it would work here, but
     // unfortunately it won't cause a repaint until the view is focused.

Source/Core/DolphinQt2/GameList/GameTracker.cpp

@@ -30,8 +30,10 @@ GameTracker::GameTracker(QObject* parent) : QFileSystemWatcher(parent)
     switch (command.type)
     {
     case CommandType::LoadCache:
-      m_cache.Load();
+      LoadCache();
       break;
+    case CommandType::Start:
+      StartInternal();
     case CommandType::AddDirectory:
       AddDirectoryInternal(command.path);
       break;
@@ -52,6 +54,52 @@ GameTracker::GameTracker(QObject* parent) : QFileSystemWatcher(parent)
   // TODO: When language changes, reload m_title_database and call m_cache.UpdateAdditionalMetadata
 }
 
+void GameTracker::LoadCache()
+{
+  std::lock_guard<std::mutex> lk(m_mutex);
+  m_cache.Load();
+}
+
+void GameTracker::Start()
+{
+  if (m_initial_games_emitted)
+    return;
+
+  m_initial_games_emitted = true;
+
+  std::lock_guard<std::mutex> lk(m_mutex);
+
+  m_load_thread.EmplaceItem(Command{CommandType::Start, {}});
+
+  m_cache.ForEach(
+      [this](const std::shared_ptr<const UICommon::GameFile>& game) { emit GameLoaded(game); });
+}
+
+void GameTracker::StartInternal()
+{
+  if (m_started)
+    return;
+
+  m_started = true;
+
+  std::vector<std::string> paths;
+  paths.reserve(m_tracked_files.size());
+  for (const QString& path : m_tracked_files.keys())
+    paths.push_back(path.toStdString());
+
+  auto emit_game_loaded = [this](const std::shared_ptr<const UICommon::GameFile>& game) {
+    emit GameLoaded(std::move(game));
+  };
+  auto emit_game_removed = [this](const std::string& path) { emit GameRemoved(path); };
+
+  std::lock_guard<std::mutex> lk(m_mutex);
+
+  bool cache_updated = m_cache.Update(paths, emit_game_loaded, emit_game_removed);
+  cache_updated |= m_cache.UpdateAdditionalMetadata(m_title_database, emit_game_loaded);
+  if (cache_updated)
+    m_cache.Save();
+}
+
 void GameTracker::AddDirectory(const QString& dir)
 {
   m_load_thread.EmplaceItem(Command{CommandType::AddDirectory, dir});
@@ -108,7 +156,8 @@ void GameTracker::RemoveDirectoryInternal(const QString& dir)
       {
         removePath(path);
         m_tracked_files.remove(path);
-        emit GameRemoved(path);
+        if (m_started)
+          emit GameRemoved(path.toStdString());
       }
     }
   }
@@ -143,7 +192,8 @@ void GameTracker::UpdateDirectoryInternal(const QString& dir)
     if (tracked_file.empty())
     {
       m_tracked_files.remove(missing);
-      GameRemoved(missing);
+      if (m_started)
+        GameRemoved(missing.toStdString());
     }
   }
 }
@@ -152,14 +202,16 @@ void GameTracker::UpdateFileInternal(const QString& file)
 {
   if (QFileInfo(file).exists())
   {
-    GameRemoved(file);
+    if (m_started)
+      GameRemoved(file.toStdString());
     addPath(file);
     LoadGame(file);
   }
   else if (removePath(file))
   {
     m_tracked_files.remove(file);
-    emit GameRemoved(file);
+    if (m_started)
+      emit GameRemoved(file.toStdString());
   }
 }
 
@@ -187,6 +239,9 @@ QSet<QString> GameTracker::FindMissingFiles(const QString& dir)
 
 void GameTracker::LoadGame(const QString& path)
 {
+  if (!m_started)
+    return;
+
   const std::string converted_path = path.toStdString();
   if (!DiscIO::ShouldHideFromGameList(converted_path))
   {

Source/Core/DolphinQt2/GameList/GameTracker.h

@@ -5,6 +5,8 @@
 #pragma once
 
 #include <memory>
+#include <mutex>
+#include <string>
 
 #include <QFileSystemWatcher>
 #include <QMap>
@@ -26,15 +28,23 @@ class GameTracker final : public QFileSystemWatcher
 public:
   explicit GameTracker(QObject* parent = nullptr);
 
+  // A GameTracker won't emit any signals until this function has been called.
+  // Before you call this function, make sure to call AddDirectory for all
+  // directories you want to track, otherwise games will briefly disappear
+  // until you call AddDirectory and the GameTracker finishes scanning the file system.
+  void Start();
+
   void AddDirectory(const QString& dir);
   void RemoveDirectory(const QString& dir);
   void ReloadDirectory(const QString& dir);
 
 signals:
   void GameLoaded(std::shared_ptr<const UICommon::GameFile> game);
-  void GameRemoved(const QString& path);
+  void GameRemoved(const std::string& path);
 
 private:
+  void LoadCache();
+  void StartInternal();
   void UpdateDirectory(const QString& dir);
   void UpdateFile(const QString& path);
   void AddDirectoryInternal(const QString& dir);
@@ -47,6 +57,7 @@ private:
   enum class CommandType
   {
     LoadCache,
+    Start,
     AddDirectory,
     RemoveDirectory,
     UpdateDirectory,
@@ -64,6 +75,10 @@ private:
   Common::WorkQueueThread<Command> m_load_thread;
   UICommon::GameFileCache m_cache;
   Core::TitleDatabase m_title_database;
+  std::mutex m_mutex;
+  bool m_started = false;
+  bool m_initial_games_emitted = false;
 };
 
 Q_DECLARE_METATYPE(std::shared_ptr<const UICommon::GameFile>)
+Q_DECLARE_METATYPE(std::string)