Detect OpenGL backend; Fix #64

src/detectopengl.cpp

@@ -0,0 +1,62 @@
+#include <mpv/client.h>
+#include <QSurfaceFormat>
+#include <QSettings>
+
+#ifdef Q_OS_MAC
+void detectOpenGL()
+{
+  // Request OpenGL 4.1 if possible on OSX, otherwise it defaults to 2.0
+  // This needs to be done before we create the QGuiApplication
+  //
+  QSurfaceFormat format = QSurfaceFormat::defaultFormat();
+  format.setMajorVersion(3);
+  format.setMinorVersion(2);
+  format.setProfile(QSurfaceFormat::CoreProfile);
+  QSurfaceFormat::setDefaultFormat(format);
+}
+#endif
+
+#ifdef Q_OS_LINUX
+// Attempt to reuse mpv's code for detecting whether we want GLX or EGL (which
+// is tricky to do because of hardware decoding concerns). This is not pretty,
+// but quite effective and without having to duplicate too much GLX/EGL code.
+static QString probeHwdecInterop()
+{
+    QString result;
+    mpv_handle *mpv = mpv_create();
+    if (!mpv)
+        return "";
+    mpv_set_option_string(mpv, "hwdec-preload", "auto");
+    mpv_set_option_string(mpv, "opengl-hwdec-interop", "auto");
+    // Actually creating a window is required. There is currently no way to keep
+    // this window hidden or invisible.
+    mpv_set_option_string(mpv, "force-window", "yes");
+    // As a mitigation, put the window in the top/right corner, and make it as
+    // small as possible by forcing 1x1 size and removing window borders.
+    mpv_set_option_string(mpv, "geometry", "1x1+0+0");
+    mpv_set_option_string(mpv, "border", "no");
+    if (mpv_initialize(mpv) < 0)
+        return "";
+    char *str = mpv_get_property_string(mpv, "hwdec-interop");
+    if (str)
+    {
+        qInfo("Detected OpenGL backend: %s", str);
+        result = str;
+        mpv_free(str);
+    }
+    mpv_terminate_destroy(mpv);
+    return result;
+}
+
+void detectOpenGL()
+{
+    QString hwdec = QSettings("moonsoft", "moonplayer").value("Video/hwdec").toString();
+    if (hwdec == "vaapi")
+        qputenv("QT_XCB_GL_INTEGRATION", "xcb_egl");
+    else if (hwdec == "auto")
+    {
+        if (probeHwdecInterop() == "vaapi-egl")
+            qputenv("QT_XCB_GL_INTEGRATION", "xcb_egl");
+    }
+}
+#endif

src/detectopengl.h

@@ -0,0 +1,6 @@
+#ifndef DETECTOPENGL_H
+#define DETECTOPENGL_H
+
+void detectOpenGL(void);
+
+#endif // DETECTOPENGL_H

src/main.cpp

@@ -10,10 +10,10 @@
 #include <QLocale>
 #include <QDebug>
 #include <QSettings>
-#include <QSurfaceFormat>
 #include <QTextCodec>
 #include <QNetworkAccessManager>
 #include <Python.h>
+#include "detectopengl.h"
 #include "pyapi.h"
 #include "platforms.h"
 #include "playerview.h"
@@ -65,15 +65,8 @@ int main(int argc, char *argv[])
 
 #if defined(Q_OS_LINUX)
     QApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
-    if (QSettings("moonsoft", "moonplayer").value("Video/hwdec").toString() != "vdpau")
-        qputenv("QT_XCB_GL_INTEGRATION", "xcb_egl");
-#elif defined(Q_OS_MAC)
-    // OpenGL version >= 3.0 is required for hardware decoding
-    QSurfaceFormat surface = QSurfaceFormat::defaultFormat();
-    surface.setVersion(3, 2);
-    surface.setProfile(QSurfaceFormat::CoreProfile);
-    QSurfaceFormat::setDefaultFormat(surface);
 #endif
+    detectOpenGL();
 
 #ifdef Q_OS_MAC
     MyApplication a(argc, argv);

src/moonplayer.pro

@@ -41,7 +41,8 @@ SOURCES += main.cpp\
     danmakudelaygetter.cpp \
     terminal.cpp \
     ykdlbridge.cpp \
-    parserbridge.cpp
+    parserbridge.cpp \
+    detectopengl.cpp
 !macx: SOURCES += localserver.cpp \
     localsocket.cpp
 
@@ -82,7 +83,8 @@ HEADERS  +=\
     playerview.h \
     terminal.h \
     ykdlbridge.h \
-    parserbridge.h
+    parserbridge.h \
+    detectopengl.h
 !macx: HEADERS += localserver.h \
     localsocket.h