Rework how to set a video output surface

Setting a video output should not require QMediaService
anymore.

Reverse the logic, by making QAbstractVideoSurface the primary
interface. Use runtime method lookup to get a pointer to the
video surface from QVideoWidget/QGraphicsVideoItem.

QAbstractVideoSurface is now the primary interface for setting
up a video output. We will need to add some API there to allow for
windows/fullscreen rendering.

With this change, QVideoRendererControl/QVideoWindowControl can
also be retired as an abstraction layer in the longer term.

Change-Id: Iedff18c6b95fedc7cb914075a8c84081080deab1
Reviewed-by: Doris Verria <doris.verria@qt.io>
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

4 files changed, 30 insertions, 41 deletions

diff --git a/src/multimedia/platform/gstreamer/common/qgstreamerplayercontrol.cpp b/src/multimedia/platform/gstreamer/common/qgstreamerplayercontrol.cpp
index c8fdd00a3..f856bc3d8 100644
--- a/src/multimedia/platform/gstreamer/common/qgstreamerplayercontrol.cpp
+++ b/src/multimedia/platform/gstreamer/common/qgstreamerplayercontrol.cpp
@@ -385,9 +385,9 @@ QMediaMetaData QGstreamerPlayerControl::metaData() const
     return m_session->metaData();
 }
 
-void QGstreamerPlayerControl::setVideoOutput(QObject *output)
+void QGstreamerPlayerControl::setVideoSurface(QAbstractVideoSurface *surface)
 {
-    m_session->setVideoRenderer(output);
+    m_session->setVideoRenderer(surface);
 }
 
 bool QGstreamerPlayerControl::isAudioAvailable() const
diff --git a/src/multimedia/platform/gstreamer/common/qgstreamerplayercontrol_p.h b/src/multimedia/platform/gstreamer/common/qgstreamerplayercontrol_p.h
index 1c4321663..a73ea1b94 100644
--- a/src/multimedia/platform/gstreamer/common/qgstreamerplayercontrol_p.h
+++ b/src/multimedia/platform/gstreamer/common/qgstreamerplayercontrol_p.h
@@ -82,7 +82,6 @@ public:
 
     bool isAudioAvailable() const override;
     bool isVideoAvailable() const override;
-    void setVideoOutput(QObject *output);
 
     bool isSeekable() const override;
     QMediaTimeRange availablePlaybackRanges() const override;
@@ -101,6 +100,8 @@ public:
 
     QMediaMetaData metaData() const override;
 
+    void setVideoSurface(QAbstractVideoSurface *surface) override;
+
 public Q_SLOTS:
     void setPosition(qint64 pos) override;
 
diff --git a/src/multimedia/platform/gstreamer/common/qgstreamerplayersession.cpp b/src/multimedia/platform/gstreamer/common/qgstreamerplayersession.cpp
index 6f4bb61d5..d63d7be89 100644
--- a/src/multimedia/platform/gstreamer/common/qgstreamerplayersession.cpp
+++ b/src/multimedia/platform/gstreamer/common/qgstreamerplayersession.cpp
@@ -40,7 +40,7 @@
 #include <private/qgstreamerplayersession_p.h>
 #include <private/qgstreamerbushelper_p.h>
 
-#include <private/qgstreamervideorendererinterface_p.h>
+#include <private/qgstreamervideorenderer_p.h>
 #include <private/qgstutils_p.h>
 #include <private/qgstvideorenderersink_p.h>
 #include <private/qgstreamermetadata_p.h>
@@ -552,42 +552,8 @@ void QGstreamerPlayerSession::updateVideoRenderer()
     qDebug() << "Video sink has chaged, reload video output";
 #endif
 
-    if (m_videoOutput)
-        setVideoRenderer(m_videoOutput);
-}
-
-void QGstreamerPlayerSession::setVideoRenderer(QObject *videoOutput)
-{
-#ifdef DEBUG_PLAYBIN
-    qDebug() << Q_FUNC_INFO;
-#endif
-    if (m_videoOutput != videoOutput) {
-        if (m_videoOutput) {
-            disconnect(m_videoOutput, SIGNAL(sinkChanged()),
-                       this, SLOT(updateVideoRenderer()));
-            disconnect(m_videoOutput, SIGNAL(readyChanged(bool)),
-                   this, SLOT(updateVideoRenderer()));
-
-            m_busHelper->removeMessageFilter(m_videoOutput);
-        }
-
-        m_videoOutput = videoOutput;
-
-        if (m_videoOutput) {
-            connect(m_videoOutput, SIGNAL(sinkChanged()),
-                    this, SLOT(updateVideoRenderer()));
-            connect(m_videoOutput, SIGNAL(readyChanged(bool)),
-                   this, SLOT(updateVideoRenderer()));
-
-            m_busHelper->installMessageFilter(m_videoOutput);
-        }
-    }
-
-    m_renderer = qobject_cast<QGstreamerVideoRendererInterface*>(videoOutput);
-    emit rendererChanged();
-
     // No sense to continue if custom pipeline requested.
-    if (!m_playbin)
+    if (!m_playbin || !m_videoOutput)
         return;
 
     GstElement *videoSink = 0;
@@ -683,6 +649,27 @@ void QGstreamerPlayerSession::setVideoRenderer(QObject *videoOutput)
     }
 }
 
+void QGstreamerPlayerSession::setVideoRenderer(QAbstractVideoSurface *videoOutput)
+{
+    if (!m_videoOutput) {
+        m_videoOutput = new QGstreamerVideoRenderer;
+#ifdef DEBUG_PLAYBIN
+    qDebug() << Q_FUNC_INFO;
+#endif
+        connect(m_videoOutput, SIGNAL(sinkChanged()),
+                this, SLOT(updateVideoRenderer()));
+        connect(m_videoOutput, SIGNAL(readyChanged(bool)),
+               this, SLOT(updateVideoRenderer()));
+
+        m_busHelper->installMessageFilter(m_videoOutput);
+        m_renderer = qobject_cast<QGstreamerVideoRendererInterface*>(m_videoOutput);
+        emit rendererChanged();
+    }
+
+    m_videoOutput->setSurface(videoOutput);
+    updateVideoRenderer();
+}
+
 void QGstreamerPlayerSession::finishVideoOutputChange()
 {
     if (!m_playbin || !m_pendingVideoSink)
diff --git a/src/multimedia/platform/gstreamer/common/qgstreamerplayersession_p.h b/src/multimedia/platform/gstreamer/common/qgstreamerplayersession_p.h
index 1a3b329a7..80594e36a 100644
--- a/src/multimedia/platform/gstreamer/common/qgstreamerplayersession_p.h
+++ b/src/multimedia/platform/gstreamer/common/qgstreamerplayersession_p.h
@@ -73,6 +73,7 @@ class QGstreamerBusHelper;
 class QGstreamerMessage;
 
 class QGstreamerVideoRendererInterface;
+class QGstreamerVideoRenderer;
 
 typedef enum {
   GST_AUTOPLUG_SELECT_TRY,
@@ -108,7 +109,7 @@ public:
 
     bool isAudioAvailable() const;
 
-    void setVideoRenderer(QObject *renderer);
+    void setVideoRenderer(QAbstractVideoSurface *renderer);
     QGstreamerVideoRendererInterface *renderer() const { return m_renderer; }
     bool isVideoAvailable() const;
 
@@ -223,7 +224,7 @@ private:
     GstElement *m_volumeElement = nullptr;
 
     GstBus *m_bus = nullptr;
-    QObject *m_videoOutput = nullptr;
+    QGstreamerVideoRenderer *m_videoOutput = nullptr;
     QGstreamerVideoRendererInterface *m_renderer = nullptr;
 
 #if QT_CONFIG(gstreamer_app)