configure.ac

@@ -996,6 +996,13 @@ AS_IF([test "${SYS}" != "mingw32"], [
 ])
 AC_SUBST([LIBRT])
 
+dnl Check for libatomic
+have_libatomic="no"
+VLC_SAVE_FLAGS
+AC_SEARCH_LIBS([__atomic_load], [atomic], [have_libatomic="yes"])
+VLC_RESTORE_FLAGS
+AM_CONDITIONAL([HAVE_LIBATOMIC], [test "${have_libatomic}" = "yes"])
+
 dnl  Check for clock_* functions, needs to be done here,
 dnl  after the -lrt check
 AC_REPLACE_FUNCS([clock_gettime clock_nanosleep clock_getres])

modules/gui/qt/Makefile.am

@@ -51,6 +51,10 @@ libqt_plugin_la_CPPFLAGS = $(AM_CPPFLAGS) $(CPPFLAGS_qt) \
 
 libqt_plugin_la_CXXFLAGS = $(AM_CXXFLAGS) $(QT_CFLAGS) $(CXXFLAGS_qt) -fPIC
 libqt_plugin_la_LIBADD = $(vlc_qt_libs)
+if HAVE_LIBATOMIC
+libqt_plugin_la_CXXFLAGS += -DQT_HAS_LIBATOMIC
+libqt_plugin_la_LIBADD += -latomic
+endif
 libqt_plugin_la_LDFLAGS = $(AM_LDFLAGS) $(QT_LDFLAGS)
 if HAVE_DARWIN
 libqt_plugin_la_LDFLAGS += -Wl,-framework,Cocoa

modules/gui/qt/meson.build

@@ -924,6 +924,12 @@ if qt6_dep.found()
         qt_rcc_extra_arguments += '-compress-algo=zlib'
     endif
 
+    libatomic = cc.find_library('atomic', required: false)
+    if libatomic.found()
+        qt_extra_deps += cc.find_library('atomic', required: false)
+        qt_extra_flags += '-DQT_HAS_LIBATOMIC'
+    endif
+
     prog_python = find_program('python3')
     modules_qrc = []
     foreach module : qml_modules

modules/gui/qt/player/player_controller.cpp

@@ -38,6 +38,10 @@
 #include <QDir>
 #include <QSignalMapper>
 #include <QThreadPool>
+#ifndef QT_HAS_LIBATOMIC
+#include <QReadLocker>
+#include <QWriteLocker>
+#endif
 
 #include <cassert>
 
@@ -1009,16 +1013,10 @@ static void on_player_timer_smpte_update(const struct vlc_player_timer_smpte_tim
                                          void *data)
 {
     PlayerControllerPrivate* that = static_cast<PlayerControllerPrivate *>(data);
-
-    that->callAsync([that, tc_copy = *tc](){
-        that->m_highResolutionTime = QString::asprintf("%02u:%02u:%02u%c%02u",
-                                                       tc_copy.hours,
-                                                       tc_copy.minutes,
-                                                       tc_copy.seconds,
-                                                       tc_copy.drop_frame ? '.' : ':',
-                                                       tc_copy.frames);
-        emit that->q_func()->highResolutionTimeChanged(that->m_highResolutionTime);
-    });
+#ifndef QT_HAS_LIBATOMIC
+    QWriteLocker lock(&that->m_highResolutionTimeLock);
+#endif
+    that->m_highResolutionTime = *tc;
 }
 
 
@@ -1953,6 +1951,39 @@ void PlayerController::snapshot()
     }
 }
 
+QString PlayerController::highResolutionTime() const
+{
+    Q_D(const PlayerController);
+
+    // Sample:
+    vlc_player_timer_smpte_timecode sample;
+    {
+#ifndef QT_HAS_LIBATOMIC
+        QReadLocker lock(&d->m_highResolutionTimeLock);
+#endif
+        sample = d->m_highResolutionTime;
+    }
+
+    const vlc_player_timer_smpte_timecode& lastSample = d->m_highResolutionTimeSample.first;
+
+    if (sample.frames == lastSample.frames &&
+        sample.frame_resolution == lastSample.frame_resolution &&
+        sample.seconds == lastSample.seconds &&
+        sample.minutes == lastSample.minutes &&
+        sample.hours == lastSample.hours &&
+        sample.drop_frame == lastSample.drop_frame)
+        return d->m_highResolutionTimeSample.second;
+
+    d->m_highResolutionTimeSample.second = QString::asprintf("%02u:%02u:%02u%c%02u",
+                                                             sample.hours,
+                                                             sample.minutes,
+                                                             sample.seconds,
+                                                             sample.drop_frame ? '.' : ':',
+                                                             sample.frames);
+    d->m_highResolutionTimeSample.first = std::move(sample);
+
+    return d->m_highResolutionTimeSample.second;
+}
 
 //OTHER
 
@@ -2137,7 +2168,4 @@ PRIMITIVETYPE_GETTER(QString, getAlbum, m_album)
 PRIMITIVETYPE_GETTER(QUrl, getArtwork, m_artwork)
 PRIMITIVETYPE_GETTER(QUrl, getUrl, m_url)
 
-// High resolution time fed by SMPTE timer
-PRIMITIVETYPE_GETTER(QString, highResolutionTime, m_highResolutionTime)
-
 #undef PRIMITIVETYPE_GETTER

modules/gui/qt/player/player_controller.hpp

@@ -196,7 +196,7 @@ public:
     Q_PROPERTY(RendererManager* rendererManager READ getRendererManager CONSTANT FINAL)
 
     // High resolution time fed by SMPTE Timer
-    Q_PROPERTY(QString highResolutionTime READ highResolutionTime NOTIFY highResolutionTimeChanged FINAL)
+    Q_PROPERTY(QString highResolutionTime READ highResolutionTime FINAL)
 
     /* exposed actions */
 public slots:

modules/gui/qt/player/player_controller_p.hpp

@@ -29,6 +29,11 @@
 #include <QTimer>
 #include <QUrl>
 
+#ifndef QT_HAS_LIBATOMIC
+#warning "libatomic is not available. Read write lock is going to be used instead."
+#include <QReadWriteLock>
+#endif
+
 typedef struct vlc_preparser_t vlc_preparser_t;
 
 class PlayerControllerPrivate {
@@ -95,7 +100,14 @@ public:
     double       m_position = 0.f;
     VLCTick      m_length= 0;
 
-    QString m_highResolutionTime { "00:00:00:00" };
+#if QT_HAS_LIBATOMIC
+    std::atomic<vlc_player_timer_smpte_timecode> m_highResolutionTime;
+#else
+    vlc_player_timer_smpte_timecode m_highResolutionTime;
+    mutable QReadWriteLock m_highResolutionTimeLock;
+#endif
+    mutable QPair<vlc_player_timer_smpte_timecode, QString> m_highResolutionTimeSample;
+
     unsigned m_smpteTimerRequestCount = 0;
 
     SharedInputItem    m_currentItem;

modules/gui/qt/player/qml/controlbarcontrols/HighResolutionTimeWidget.qml

@@ -17,6 +17,7 @@
  *****************************************************************************/
 
 import QtQuick
+import QtQuick.Window
 import QtQuick.Controls
 
 
@@ -37,7 +38,7 @@ Control {
     Keys.onPressed: (event) => Navigation.defaultKeyAction(event)
 
     Accessible.role: Accessible.Indicator
-    Accessible.name:  paintOnly ? "00:00:00:00" : Player.highResolutionTime
+    Accessible.name: contentItem.text
 
     function _adjustSMPTETimer(add) {
         if (typeof toolbarEditor !== "undefined") // FIXME: Can't use paintOnly because it is set later
@@ -73,16 +74,46 @@ Control {
         implicitHeight: smpteTimecodeMetrics.height
         implicitWidth: smpteTimecodeMetrics.width
 
+        property alias text: label.text
+
         Widgets.MenuLabel {
             id: label
             anchors.fill: parent
 
-            text: paintOnly ? "00:00:00:00" : Player.highResolutionTime
+            text: paintOnly ? "00:00:00:00" : timeText
             color: theme.fg.primary
 
             horizontalAlignment: Text.AlignHCenter
 
             Accessible.ignored: true
+
+            property string timeText
+
+            Connections {
+                target: label.Window.window
+                enabled: label.visible
+
+                function onAfterAnimating() {
+                    // Sampling point
+                    // Emitted from the GUI thread
+
+                    // Constantly update the label, so that the window
+                    // prepares new frames as we don't know when the
+                    // timecode changes. This is similar to animations:
+                    label.update()
+
+                    if (label.timeText === Player.highResolutionTime)
+                        return
+
+                    label.timeText = Player.highResolutionTime
+
+                    // Text would like polishing after text change.
+                    // We need this because `afterAnimating()` is
+                    // signalled after the items are polished:
+                    if (label.ensurePolished)
+                        label.ensurePolished()
+                }
+            }
         }
 
         TextMetrics {