Remove DefaultSharedContext from Lighthouse API.

QPlatformWindowFormat::setUseDefaultSharedContext was meant as a
convenience, but it adds complexity in the platform plugin
implementation, and can be implemented by the above layers using
QPlatformWindowFormat::setSharedContext.

Reviewed-by: Jørgen Lind

18 files changed, 18 insertions, 199 deletions

diff --git a/src/gui/kernel/qplatformglcontext_qpa.cpp b/src/gui/kernel/qplatformglcontext_qpa.cpp
index 86740e8..1810532 100644
--- a/src/gui/kernel/qplatformglcontext_qpa.cpp
+++ b/src/gui/kernel/qplatformglcontext_qpa.cpp
@@ -125,24 +125,6 @@ QPlatformGLContext::~QPlatformGLContext()
 
 }
 
-
-/*!
-    Makes it possible to set the context which can be the default for making new contexts.
-*/
-void QPlatformGLContext::setDefaultSharedContext(QPlatformGLContext *sharedContext)
-{
-    QPlatformGLContextPrivate::staticSharedContext = sharedContext;
-}
-
-/*!
-    Default shared context is intended to be a globally awailable pointer to a context which can
-    be used for sharing resources when creating new contexts. Its default value is 0;
-*/
-QPlatformGLContext *QPlatformGLContext::defaultSharedContext()
-{
-    return QPlatformGLContextPrivate::staticSharedContext;
-}
-
 /*!
     Reimplement in subclass to do makeCurrent on native GL context
 */
diff --git a/src/gui/kernel/qplatformglcontext_qpa.h b/src/gui/kernel/qplatformglcontext_qpa.h
index a680c85..28923a9 100644
--- a/src/gui/kernel/qplatformglcontext_qpa.h
+++ b/src/gui/kernel/qplatformglcontext_qpa.h
@@ -69,13 +69,10 @@ public:
     virtual QPlatformWindowFormat platformWindowFormat() const = 0;
 
     const static QPlatformGLContext *currentContext();
-    static QPlatformGLContext *defaultSharedContext();
 
 protected:
-
-    static void setDefaultSharedContext(QPlatformGLContext *sharedContext);
-
     QScopedPointer<QPlatformGLContextPrivate> d_ptr;
+
 private:
     //hack to make it work with QGLContext::CurrentContext
     friend class QGLContext;
diff --git a/src/gui/kernel/qplatformwindowformat_qpa.cpp b/src/gui/kernel/qplatformwindowformat_qpa.cpp
index ddc6239..c165c85 100644
--- a/src/gui/kernel/qplatformwindowformat_qpa.cpp
+++ b/src/gui/kernel/qplatformwindowformat_qpa.cpp
@@ -53,7 +53,7 @@ public:
         , opts(QPlatformWindowFormat::DoubleBuffer | QPlatformWindowFormat::DepthBuffer
              | QPlatformWindowFormat::Rgba | QPlatformWindowFormat::DirectRendering
              | QPlatformWindowFormat::StencilBuffer | QPlatformWindowFormat::DeprecatedFunctions
-             | QPlatformWindowFormat::UseDefaultSharedContext | QPlatformWindowFormat::HasWindowSurface)
+             | QPlatformWindowFormat::HasWindowSurface)
         , depthSize(-1)
         , accumSize(-1)
         , stencilSize(-1)
@@ -525,16 +525,6 @@ void QPlatformWindowFormat::setSampleBuffers(bool enable)
     setOption(enable ? QPlatformWindowFormat::SampleBuffers : QPlatformWindowFormat::NoSampleBuffers);
 }
 
-void QPlatformWindowFormat::setUseDefaultSharedContext(bool enable)
-{
-    if (enable) {
-        setOption(QPlatformWindowFormat::UseDefaultSharedContext);
-        d->sharedContext = 0;
-    } else {
-        setOption(QPlatformWindowFormat::NoDefaultSharedContext);
-    }
-}
-
 /*!
     Returns the number of samples per pixel when multisampling is
     enabled. By default, the highest number of samples that is
@@ -613,7 +603,6 @@ QPlatformWindowFormat::WindowApi QPlatformWindowFormat::windowApi() const
 
 void QPlatformWindowFormat::setSharedContext(QPlatformGLContext *context)
 {
-    setUseDefaultSharedContext(false);
     d->sharedContext = context;
 }
 
diff --git a/src/gui/kernel/qplatformwindowformat_qpa.h b/src/gui/kernel/qplatformwindowformat_qpa.h
index fa01a8a..ba21ba4 100644
--- a/src/gui/kernel/qplatformwindowformat_qpa.h
+++ b/src/gui/kernel/qplatformwindowformat_qpa.h
@@ -66,8 +66,7 @@ public:
         HasOverlay              = 0x0100,
         SampleBuffers           = 0x0200,
         DeprecatedFunctions     = 0x0400,
-        UseDefaultSharedContext = 0x0800,
-        HasWindowSurface        = 0x1000,
+        HasWindowSurface        = 0x0800,
         SingleBuffer            = DoubleBuffer    << 16,
         NoDepthBuffer           = DepthBuffer     << 16,
         ColorIndex              = Rgba            << 16,
@@ -79,7 +78,6 @@ public:
         NoOverlay               = HasOverlay      << 16,
         NoSampleBuffers         = SampleBuffers   << 16,
         NoDeprecatedFunctions   = DeprecatedFunctions << 16,
-        NoDefaultSharedContext  = UseDefaultSharedContext << 16,
         NoWindowSurface         = HasWindowSurface << 16
 
     };
@@ -149,8 +147,6 @@ public:
     void setStereo(bool enable);
     bool directRendering() const;
     void setDirectRendering(bool enable);
-    bool useDefaultSharedContext() const;
-    void setUseDefaultSharedContext(bool enable);
     bool hasWindowSurface() const;
     void setWindowSurface(bool enable);
 
@@ -231,11 +227,6 @@ inline bool QPlatformWindowFormat::sampleBuffers() const
     return testOption(QPlatformWindowFormat::SampleBuffers);
 }
 
-inline bool QPlatformWindowFormat::useDefaultSharedContext() const
-{
-    return testOption(QPlatformWindowFormat::UseDefaultSharedContext);
-}
-
 QT_END_NAMESPACE
 
 QT_END_HEADER
diff --git a/src/opengl/qwindowsurface_gl.cpp b/src/opengl/qwindowsurface_gl.cpp
index 681ab69..a6489a6 100644
--- a/src/opengl/qwindowsurface_gl.cpp
+++ b/src/opengl/qwindowsurface_gl.cpp
@@ -181,7 +181,6 @@ QGLGraphicsSystem::QGLGraphicsSystem(bool useX11GL)
 //
 // QGLWindowSurface
 //
-#ifndef Q_WS_QPA
 class QGLGlobalShareWidget
 {
 public:
@@ -257,22 +256,13 @@ void qt_destroy_gl_share_widget()
 {
     _qt_gl_share_widget()->destroy();
 }
-#endif//Q_WS_QPA
 
 const QGLContext *qt_gl_share_context()
 {
-#ifdef Q_WS_QPA
-    //make it possible to have an assesor to defaultSharedGLContext.
-    const QPlatformGLContext *platformContext = QPlatformGLContext::defaultSharedContext();
-    if (!platformContext)
-        qDebug() << "Please implement a defaultSharedContext for your platformplugin";
-    return QGLContext::fromPlatformGLContext(const_cast<QPlatformGLContext *>(platformContext));
-#else
     QGLWidget *widget = qt_gl_share_widget();
     if (widget)
         return widget->context();
     return 0;
-#endif
 }
 
 #ifdef QGL_USE_TEXTURE_POOL
@@ -405,7 +395,6 @@ QGLWindowSurface::~QGLWindowSurface()
     delete d_ptr->fbo;
     delete d_ptr;
 
-#ifndef Q_WS_QPA
     if (QGLGlobalShareWidget::cleanedUp)
         return;
 
@@ -426,7 +415,6 @@ QGLWindowSurface::~QGLWindowSurface()
             qt_destroy_gl_share_widget();
     }
 #endif // QGL_USE_TEXTURE_POOL
-#endif // Q_WS_QPA
 }
 
 void QGLWindowSurface::deleted(QObject *object)
@@ -476,10 +464,8 @@ void QGLWindowSurface::hijackWindow(QWidget *widget)
 
     ctx->create(qt_gl_share_context());
 
-#ifndef Q_WS_QPA
     if (widget != qt_gl_share_widget())
         ++(_qt_gl_share_widget()->widgetRefCount);
-#endif
 
 #ifndef QT_NO_EGL
     static bool checkedForNOKSwapRegion = false;
diff --git a/src/opengl/qwindowsurface_gl_p.h b/src/opengl/qwindowsurface_gl_p.h
index 67f9f41..a8d8381 100644
--- a/src/opengl/qwindowsurface_gl_p.h
+++ b/src/opengl/qwindowsurface_gl_p.h
@@ -66,12 +66,8 @@ class QRegion;
 class QWidget;
 struct QGLWindowSurfacePrivate;
 
-#ifdef Q_WS_QPA
-Q_OPENGL_EXPORT const QGLContext* qt_gl_share_context();
-#else
 Q_OPENGL_EXPORT QGLWidget* qt_gl_share_widget();
 Q_OPENGL_EXPORT void qt_destroy_gl_share_widget();
-#endif
 
 class QGLWindowSurfaceGLPaintDevice : public QGLPaintDevice
 {
diff --git a/src/plugins/platforms/eglconvenience/qeglplatformcontext.cpp b/src/plugins/platforms/eglconvenience/qeglplatformcontext.cpp
index 9a2bc61..ae5215f 100644
--- a/src/plugins/platforms/eglconvenience/qeglplatformcontext.cpp
+++ b/src/plugins/platforms/eglconvenience/qeglplatformcontext.cpp
@@ -146,11 +146,6 @@ void* QEGLPlatformContext::getProcAddress(const QString& procName)
     return (void *)eglGetProcAddress(qPrintable(procName));
 }
 
-void QEGLPlatformContext::makeDefaultSharedContext()
-{
-    setDefaultSharedContext(this);
-}
-
 QPlatformWindowFormat QEGLPlatformContext::platformWindowFormat() const
 {
     return m_windowFormat;
diff --git a/src/plugins/platforms/eglconvenience/qeglplatformcontext.h b/src/plugins/platforms/eglconvenience/qeglplatformcontext.h
index d688660..69835d7 100644
--- a/src/plugins/platforms/eglconvenience/qeglplatformcontext.h
+++ b/src/plugins/platforms/eglconvenience/qeglplatformcontext.h
@@ -56,8 +56,6 @@ public:
     void swapBuffers();
     void* getProcAddress(const QString& procName);
 
-    void makeDefaultSharedContext();
-
     QPlatformWindowFormat platformWindowFormat() const;
 
     EGLContext eglContext() const;
diff --git a/src/plugins/platforms/eglfs/qeglfsscreen.cpp b/src/plugins/platforms/eglfs/qeglfsscreen.cpp
index 2200d1d..b6f2805 100644
--- a/src/plugins/platforms/eglfs/qeglfsscreen.cpp
+++ b/src/plugins/platforms/eglfs/qeglfsscreen.cpp
@@ -203,7 +203,6 @@ void QEglFSScreen::createAndSetPlatformContext()
     attribList[temp++] = EGL_NONE;
 
     QEGLPlatformContext *platformContext = new QEGLPlatformContext(m_dpy,config,attribList,m_surface,EGL_OPENGL_ES_API);
-    platformContext->makeDefaultSharedContext();
     m_platformContext = platformContext;
 
     EGLint w,h;                    // screen size detection
diff --git a/src/plugins/platforms/openkode/qopenkodeintegration.cpp b/src/plugins/platforms/openkode/qopenkodeintegration.cpp
index 35e744be..e98f322 100644
--- a/src/plugins/platforms/openkode/qopenkodeintegration.cpp
+++ b/src/plugins/platforms/openkode/qopenkodeintegration.cpp
@@ -122,7 +122,9 @@ QOpenKODEScreen::QOpenKODEScreen(KDDisplayNV *kdDisplay,  KDDesktopNV *kdDesktop
 }
 
 QOpenKODEIntegration::QOpenKODEIntegration()
-    : mEventLoopIntegration(0), mFontDb(new QGenericUnixFontDatabase())
+    : mEventLoopIntegration(0)
+    , mFontDb(new QGenericUnixFontDatabase())
+    , mMainGlContext(0)
 {
     if (kdInitializeNV() == KD_ENOTINITIALIZED) {
         qFatal("Did not manage to initialize openkode");
diff --git a/src/plugins/platforms/openkode/qopenkodeintegration.h b/src/plugins/platforms/openkode/qopenkodeintegration.h
index 7582e60..a788091 100644
--- a/src/plugins/platforms/openkode/qopenkodeintegration.h
+++ b/src/plugins/platforms/openkode/qopenkodeintegration.h
@@ -106,10 +106,14 @@ public:
 
     static GLuint blitterProgram();
 
+    void setMainGLContext(QEGLPlatformContext *ctx) { mMainGlContext = ctx; }
+    void mainGLContext() const { return mMainGlContext; }
+
 private:
     QList<QPlatformScreen *> mScreens;
     QOpenKODEEventLoopIntegration *mEventLoopIntegration;
     QPlatformFontDatabase *mFontDb;
+    QEGLPlatformContext *mMainGlContext;
 };
 
 QT_END_NAMESPACE
diff --git a/src/plugins/platforms/openkode/qopenkodewindow.cpp b/src/plugins/platforms/openkode/qopenkodewindow.cpp
index 66530a5..d34dff8 100644
--- a/src/plugins/platforms/openkode/qopenkodewindow.cpp
+++ b/src/plugins/platforms/openkode/qopenkodewindow.cpp
@@ -147,9 +147,9 @@ QOpenKODEWindow::QOpenKODEWindow(QWidget *tlw)
     }
 
 
+    QOpenKODEIntegration *integration = static_cast<QOpenKODEIntegration *>(QApplicationPrivate::platformIntegration());
 
-
-    if (!isFullScreen || (isFullScreen && !QPlatformGLContext::defaultSharedContext())) {
+    if (!isFullScreen || (isFullScreen && !integration->mainGLContext())) {
         if (kdRealizeWindow(m_kdWindow, &m_eglWindow)) {
             qErrnoWarning(kdGetError(), "Could not realize native window");
             return;
@@ -158,9 +158,9 @@ QOpenKODEWindow::QOpenKODEWindow(QWidget *tlw)
         EGLSurface surface = eglCreateWindowSurface(screen->eglDisplay(),m_eglConfig,m_eglWindow,m_eglWindowAttrs.constData());
         m_platformGlContext = new QEGLPlatformContext(screen->eglDisplay(), m_eglConfig,
                                                       m_eglContextAttrs.data(), surface, m_eglApi);
-        m_platformGlContext->makeDefaultSharedContext();
+        integration->setMainGLContext(m_platformGLContext);
     } else {
-        m_platformGlContext = const_cast<QEGLPlatformContext *>(static_cast<const QEGLPlatformContext *>(QPlatformGLContext::defaultSharedContext()));
+        m_platformGlContext = integration->mainGLContext();
         kdDestroyWindow(m_kdWindow);
         m_kdWindow = 0;
     }
@@ -169,7 +169,7 @@ QOpenKODEWindow::QOpenKODEWindow(QWidget *tlw)
 
 QOpenKODEWindow::~QOpenKODEWindow()
 {
-    if (m_platformGlContext != QPlatformGLContext::defaultSharedContext()) {
+    if (m_platformGlContext != static_cast<QOpenKODEIntegration *>(QApplicationPrivate::platformIntegration())) {
         delete m_platformGlContext;
     }
     if (m_kdWindow)
diff --git a/src/plugins/platforms/wayland/gl_integration/wayland_egl/qwaylandglcontext.cpp b/src/plugins/platforms/wayland/gl_integration/wayland_egl/qwaylandglcontext.cpp
index 89ba12b..d293019 100644
--- a/src/plugins/platforms/wayland/gl_integration/wayland_egl/qwaylandglcontext.cpp
+++ b/src/plugins/platforms/wayland/gl_integration/wayland_egl/qwaylandglcontext.cpp
@@ -50,8 +50,6 @@
 #include <QtGui/QPlatformWindowFormat>
 #include <QtCore/QMutex>
 
-Q_GLOBAL_STATIC(QMutex,qt_defaultSharedContextMutex)
-
 QWaylandGLContext::QWaylandGLContext(EGLDisplay eglDisplay, const QPlatformWindowFormat &format)
     : QPlatformGLContext()
     , mEglDisplay(eglDisplay)
@@ -60,20 +58,7 @@ QWaylandGLContext::QWaylandGLContext(EGLDisplay eglDisplay, const QPlatformWindo
     , mFormat(qt_qPlatformWindowFormatFromConfig(mEglDisplay,mConfig))
 {
     QPlatformGLContext *sharePlatformContext = 0;
-    if (format.useDefaultSharedContext()) {
-        if (!QPlatformGLContext::defaultSharedContext()) {
-            if (qt_defaultSharedContextMutex()->tryLock()){
-                createDefaultSharedContext(eglDisplay);
-                qt_defaultSharedContextMutex()->unlock();
-            } else {
-                qt_defaultSharedContextMutex()->lock(); //wait to the the shared context is created
-                qt_defaultSharedContextMutex()->unlock();
-            }
-        }
-        sharePlatformContext = QPlatformGLContext::defaultSharedContext();
-    } else {
-        sharePlatformContext = format.sharedGLContext();
-    }
+    sharePlatformContext = format.sharedGLContext();
     mFormat.setSharedContext(sharePlatformContext);
     EGLContext shareEGLContext = EGL_NO_CONTEXT;
     if (sharePlatformContext)
@@ -128,20 +113,6 @@ void *QWaylandGLContext::getProcAddress(const QString &string)
     return (void *) eglGetProcAddress(string.toLatin1().data());
 }
 
-void QWaylandGLContext::createDefaultSharedContext(EGLDisplay display)
-{
-    QVector<EGLint> eglContextAttrs;
-    eglContextAttrs.append(EGL_CONTEXT_CLIENT_VERSION);
-    eglContextAttrs.append(2);
-    eglContextAttrs.append(EGL_NONE);
-
-    QWaylandGLContext *defaultSharedContext = new QWaylandGLContext;
-    defaultSharedContext->mEglDisplay = display;
-    defaultSharedContext->mContext = eglCreateContext(mEglDisplay,mConfig,
-                                                      EGL_NO_CONTEXT, eglContextAttrs.constData());
-    QPlatformGLContext::setDefaultSharedContext(defaultSharedContext);
-}
-
 void QWaylandGLContext::setEglSurface(EGLSurface surface)
 {
     doneCurrent();
diff --git a/src/plugins/platforms/wayland/gl_integration/wayland_egl/qwaylandglcontext.h b/src/plugins/platforms/wayland/gl_integration/wayland_egl/qwaylandglcontext.h
index a3befdc..76caffa 100644
--- a/src/plugins/platforms/wayland/gl_integration/wayland_egl/qwaylandglcontext.h
+++ b/src/plugins/platforms/wayland/gl_integration/wayland_egl/qwaylandglcontext.h
@@ -72,7 +72,6 @@ private:
     EGLConfig mConfig;
     QPlatformWindowFormat mFormat;
 
-    void createDefaultSharedContext(EGLDisplay eglDisplay);
     QWaylandGLContext();
 
 };
diff --git a/src/plugins/platforms/xcb/qglxintegration.cpp b/src/plugins/platforms/xcb/qglxintegration.cpp
index 19a9503..190221c 100644
--- a/src/plugins/platforms/xcb/qglxintegration.cpp
+++ b/src/plugins/platforms/xcb/qglxintegration.cpp
@@ -57,8 +57,6 @@
 #include <dlfcn.h>
 #endif
 
-QMutex QGLXContext::m_defaultSharedContextMutex(QMutex::Recursive);
-
 QGLXContext::QGLXContext(Window window, QXcbScreen *screen, const QPlatformWindowFormat &format)
     : QPlatformGLContext()
     , m_screen(screen)
@@ -67,20 +65,7 @@ QGLXContext::QGLXContext(Window window, QXcbScreen *screen, const QPlatformWindo
 {
     Q_XCB_NOOP(m_screen->connection());
     const QPlatformGLContext *sharePlatformContext;
-    if (format.useDefaultSharedContext()) {
-        if (!QPlatformGLContext::defaultSharedContext()) {
-            if (m_defaultSharedContextMutex.tryLock()){
-                createDefaultSharedContext(screen);
-                m_defaultSharedContextMutex.unlock();
-            } else {
-                m_defaultSharedContextMutex.lock(); //wait to the the shared context is created
-                m_defaultSharedContextMutex.unlock();
-            }
-        }
-        sharePlatformContext = QPlatformGLContext::defaultSharedContext();
-    } else {
-        sharePlatformContext = format.sharedGLContext();
-    }
+    sharePlatformContext = format.sharedGLContext();
     GLXContext shareGlxContext = 0;
     if (sharePlatformContext)
         shareGlxContext = static_cast<const QGLXContext*>(sharePlatformContext)->glxContext();
@@ -105,35 +90,6 @@ QGLXContext::~QGLXContext()
     Q_XCB_NOOP(m_screen->connection());
 }
 
-void QGLXContext::createDefaultSharedContext(QXcbScreen *screen)
-{
-    Q_XCB_NOOP(screen->connection());
-    int x = 0;
-    int y = 0;
-    int w = 3;
-    int h = 3;
-
-    QPlatformWindowFormat format = QPlatformWindowFormat::defaultFormat();
-    GLXContext context;
-    GLXFBConfig config = qglx_findConfig(DISPLAY_FROM_XCB(screen),screen->screenNumber(),format);
-    if (config) {
-        XVisualInfo *visualInfo = glXGetVisualFromFBConfig(DISPLAY_FROM_XCB(screen), config);
-        Colormap cmap = XCreateColormap(DISPLAY_FROM_XCB(screen), screen->root(), visualInfo->visual, AllocNone);
-        XSetWindowAttributes a;
-        a.colormap = cmap;
-        Window sharedWindow = XCreateWindow(DISPLAY_FROM_XCB(screen), screen->root(), x, y, w, h,
-                                  0, visualInfo->depth, InputOutput, visualInfo->visual,
-                                  CWColormap, &a);
-
-        context = glXCreateNewContext(DISPLAY_FROM_XCB(screen), config, GLX_RGBA_TYPE, 0, TRUE);
-        QPlatformGLContext *sharedContext = new QGLXContext(screen, sharedWindow, context);
-        QPlatformGLContext::setDefaultSharedContext(sharedContext);
-    } else {
-        qWarning("Warning no shared context created");
-    }
-    Q_XCB_NOOP(screen->connection());
-}
-
 void QGLXContext::makeCurrent()
 {
     Q_XCB_NOOP(m_screen->connection());
diff --git a/src/plugins/platforms/xcb/qglxintegration.h b/src/plugins/platforms/xcb/qglxintegration.h
index 2e19cf2..99b72a0 100644
--- a/src/plugins/platforms/xcb/qglxintegration.h
+++ b/src/plugins/platforms/xcb/qglxintegration.h
@@ -73,8 +73,6 @@ private:
     QPlatformWindowFormat m_windowFormat;
 
     QGLXContext (QXcbScreen *screen, Drawable drawable, GLXContext context);
-    static QMutex m_defaultSharedContextMutex;
-    static void createDefaultSharedContext(QXcbScreen *xd);
 };
 
 #endif
diff --git a/src/plugins/platforms/xlib/qglxintegration.cpp b/src/plugins/platforms/xlib/qglxintegration.cpp
index 6746e22..7a0f36d 100644
--- a/src/plugins/platforms/xlib/qglxintegration.cpp
+++ b/src/plugins/platforms/xlib/qglxintegration.cpp
@@ -61,8 +61,6 @@
 
 QT_BEGIN_NAMESPACE
 
-QMutex QGLXContext::m_defaultSharedContextMutex(QMutex::Recursive);
-
 QGLXContext::QGLXContext(Window window, QXlibScreen *screen, const QPlatformWindowFormat &format)
     : QPlatformGLContext()
     , m_screen(screen)
@@ -71,20 +69,7 @@ QGLXContext::QGLXContext(Window window, QXlibScreen *screen, const QPlatformWind
 {
 
     const QPlatformGLContext *sharePlatformContext;
-    if (format.useDefaultSharedContext()) {
-        if (!QPlatformGLContext::defaultSharedContext()) {
-            if (m_defaultSharedContextMutex.tryLock()){
-                createDefaultSharedContext(screen);
-                m_defaultSharedContextMutex.unlock();
-            } else {
-                m_defaultSharedContextMutex.lock(); //wait to the the shared context is created
-                m_defaultSharedContextMutex.unlock();
-            }
-        }
-        sharePlatformContext = QPlatformGLContext::defaultSharedContext();
-    } else {
-        sharePlatformContext = format.sharedGLContext();
-    }
+    sharePlatformContext = format.sharedGLContext();
     GLXContext shareGlxContext = 0;
     if (sharePlatformContext)
         shareGlxContext = static_cast<const QGLXContext*>(sharePlatformContext)->glxContext();
@@ -112,33 +97,6 @@ QGLXContext::~QGLXContext()
     }
 }
 
-void QGLXContext::createDefaultSharedContext(QXlibScreen *screen)
-{
-    int x = 0;
-    int y = 0;
-    int w = 3;
-    int h = 3;
-
-    QPlatformWindowFormat format = QPlatformWindowFormat::defaultFormat();
-    GLXContext context;
-    GLXFBConfig config = qglx_findConfig(screen->display()->nativeDisplay(),screen->xScreenNumber(),format);
-    if (config) {
-        XVisualInfo *visualInfo = glXGetVisualFromFBConfig(screen->display()->nativeDisplay(),config);
-        Colormap cmap = XCreateColormap(screen->display()->nativeDisplay(),screen->rootWindow(),visualInfo->visual,AllocNone);
-        XSetWindowAttributes a;
-        a.colormap = cmap;
-        Window sharedWindow = XCreateWindow(screen->display()->nativeDisplay(), screen->rootWindow(),x, y, w, h,
-                                  0, visualInfo->depth, InputOutput, visualInfo->visual,
-                                  CWColormap, &a);
-
-        context = glXCreateNewContext(screen->display()->nativeDisplay(),config,GLX_RGBA_TYPE,0,TRUE);
-        QPlatformGLContext *sharedContext = new QGLXContext(screen,sharedWindow,context);
-        QPlatformGLContext::setDefaultSharedContext(sharedContext);
-    } else {
-        qWarning("Warning no shared context created");
-    }
-}
-
 void QGLXContext::makeCurrent()
 {
     QPlatformGLContext::makeCurrent();
diff --git a/src/plugins/platforms/xlib/qglxintegration.h b/src/plugins/platforms/xlib/qglxintegration.h
index cf6b006..57c716b 100644
--- a/src/plugins/platforms/xlib/qglxintegration.h
+++ b/src/plugins/platforms/xlib/qglxintegration.h
@@ -76,8 +76,6 @@ private:
     QPlatformWindowFormat m_windowFormat;
 
     QGLXContext (QXlibScreen *screen, Drawable drawable, GLXContext context);
-    static QMutex m_defaultSharedContextMutex;
-    static void createDefaultSharedContext(QXlibScreen *xd);
 };
 
 QT_END_NAMESPACE