gui, spline-widget, compat/options: ensure no qsettings IO when not modified

Turns out every MainWindow::save() and friends were doing useless IO
several times during each save. I blame the bundle abstraction.

For bundles we track the modified state, but the spline widget needs
equality check since it doesn't use the options api.

It was found by accident when adding qDebug() into the slider_value
{de,}serializer code. The .ini file was being rewritten over and over
again causing hundres of milliseconds pauses on Windows.

Remove the save timer kludge from gui. Saves are now fast.

2 files changed, 4 insertions, 26 deletions

diff --git a/gui/ui.cpp b/gui/ui.cpp
index fabcb5e4..40ac6c8d 100644
--- a/gui/ui.cpp
+++ b/gui/ui.cpp
@@ -74,9 +74,6 @@ MainWindow::MainWindow() :
     connect(&pose_update_timer, SIGNAL(timeout()), this, SLOT(showHeadPose()));
     connect(&kbd_quit, SIGNAL(activated()), this, SLOT(exit()));
 
-    save_timer.setSingleShot(true);
-    connect(&save_timer, SIGNAL(timeout()), this, SLOT(_save()));
-
     profile_menu.addAction("Create new empty config", this, SLOT(make_empty_config()));
     profile_menu.addAction("Create new copied config", this, SLOT(make_copied_config()));
     profile_menu.addAction("Open configuration directory", this, SLOT(open_config_directory()));
@@ -156,11 +153,10 @@ bool MainWindow::get_new_config_name_from_dialog(QString& ret)
 
 MainWindow::~MainWindow()
 {
-    maybe_save();
-
     if (tray)
         tray->hide();
     stopTracker();
+    save();
 }
 
 void MainWindow::set_working_directory()
@@ -168,30 +164,15 @@ void MainWindow::set_working_directory()
     QDir::setCurrent(QCoreApplication::applicationDirPath());
 }
 
-void MainWindow::save_mappings() {
+void MainWindow::save_mappings()
+{
     pose.save_mappings();
 }
 
 void MainWindow::save()
 {
-    save_timer.stop();
-    save_timer.start(5000);
-}
-
-void MainWindow::maybe_save()
-{
-    if (save_timer.isActive())
-    {
-        save_timer.stop();
-        _save();
-    }
-}
-
-void MainWindow::_save() {
     s.b->save();
     save_mappings();
-    mem<QSettings> settings = group::ini_file();
-    settings->sync();
 
 #if defined(__unix) || defined(__linux)
     QString currentFile = group::ini_pathname();
diff --git a/gui/ui.h b/gui/ui.h
index fbfd1237..42c4630c 100644
--- a/gui/ui.h
+++ b/gui/ui.h
@@ -38,7 +38,7 @@ using namespace options;
 class MainWindow : public QMainWindow, private State
 {
     Q_OBJECT
-    
+
     Shortcuts global_shortcuts;
 
     Ui::OpentrackUI ui;
@@ -55,7 +55,6 @@ class MainWindow : public QMainWindow, private State
     process_detector_worker det;
     QMenu profile_menu;
     bool is_refreshing_profiles;
-    QTimer save_timer;
 
     mem<dylib> current_tracker()
     {
@@ -79,10 +78,8 @@ class MainWindow : public QMainWindow, private State
     void set_title(const QString& game_title = QStringLiteral(""));
     static bool get_new_config_name_from_dialog(QString &ret);
     void set_profile(const QString& profile);
-    void maybe_save();
     void register_shortcuts();
 private slots:
-    void _save();
     void save();
     void exit();
     void profileSelected(QString name);