Taken from: https://code.qt.io/cgit/qt/qtbase.git/patch/?id=0c183117 From 0c1831178540462da31fd7a4b6d2e446bc84498b Mon Sep 17 00:00:00 2001 From: Erik Kurzinger Date: Thu, 13 Jun 2019 08:15:50 -0700 Subject: Track swap interval in QXcbWindow As per GLX_EXT_swap_control, the GLX swap interval is specified on a per-drawable basis. However, QGLXContext only tracks it per-context using the m_swapInterval member. If a new drawable is made current to a context, it is still necessary to call glXSwapIntervalEXT to change the swap interval, even if it has been previously called for the same context with a different drawable. However, currently, QGLXContext::makeCurrent doesn't do this if its m_swapInterval field matches the new swap interval. This change removes m_swapInterval from QGLXContext, instead tracking it in QXcbWindow. This still avoids unnecessary calls to glXSwapIntervalEXT, while ensuring the swap interval is always set for new window drawables. Change-Id: Idc34101476c6af618059f6f3d8925dee743994a3 Reviewed-by: Giuseppe D'Angelo Reviewed-by: Laszlo Agocs --- .../platforms/xcb/gl_integrations/xcb_glx/qglxintegration.cpp | 6 +++--- src/plugins/platforms/xcb/gl_integrations/xcb_glx/qglxintegration.h | 1 - src/plugins/platforms/xcb/qxcbwindow.h | 4 ++++ 3 files changed, 7 insertions(+), 4 deletions(-) diff --git a/src/plugins/platforms/xcb/gl_integrations/xcb_glx/qglxintegration.cpp b/src/plugins/platforms/xcb/gl_integrations/xcb_glx/qglxintegration.cpp index 4adf662152..f26f698e76 100644 --- a/src/plugins/platforms/xcb/gl_integrations/xcb_glx/qglxintegration.cpp +++ b/src/plugins/platforms/xcb/gl_integrations/xcb_glx/qglxintegration.cpp @@ -204,7 +204,6 @@ QGLXContext::QGLXContext(QXcbScreen *screen, const QSurfaceFormat &format, QPlat , m_shareContext(0) , m_format(format) , m_isPBufferCurrent(false) - , m_swapInterval(-1) , m_ownsContext(nativeHandle.isNull()) , m_getGraphicsResetStatus(0) , m_lost(false) @@ -567,9 +566,9 @@ bool QGLXContext::makeCurrent(QPlatformSurface *surface) if (success && surfaceClass == QSurface::Window) { int interval = surface->format().swapInterval(); + QXcbWindow *window = static_cast(surface); QXcbScreen *screen = screenForPlatformSurface(surface); - if (interval >= 0 && m_swapInterval != interval && screen) { - m_swapInterval = interval; + if (interval >= 0 && interval != window->swapInterval() && screen) { typedef void (*qt_glXSwapIntervalEXT)(Display *, GLXDrawable, int); typedef void (*qt_glXSwapIntervalMESA)(unsigned int); static qt_glXSwapIntervalEXT glXSwapIntervalEXT = 0; @@ -588,6 +587,7 @@ bool QGLXContext::makeCurrent(QPlatformSurface *surface) glXSwapIntervalEXT(m_display, glxDrawable, interval); else if (glXSwapIntervalMESA) glXSwapIntervalMESA(interval); + window->setSwapInterval(interval); } } diff --git a/src/plugins/platforms/xcb/gl_integrations/xcb_glx/qglxintegration.h b/src/plugins/platforms/xcb/gl_integrations/xcb_glx/qglxintegration.h index be9d3f5dcb..2a88fd6e59 100644 --- a/src/plugins/platforms/xcb/gl_integrations/xcb_glx/qglxintegration.h +++ b/src/plugins/platforms/xcb/gl_integrations/xcb_glx/qglxintegration.h @@ -87,7 +87,6 @@ private: GLXContext m_shareContext; QSurfaceFormat m_format; bool m_isPBufferCurrent; - int m_swapInterval; bool m_ownsContext; GLenum (APIENTRY * m_getGraphicsResetStatus)(); bool m_lost; diff --git a/src/plugins/platforms/xcb/qxcbwindow.h b/src/plugins/platforms/xcb/qxcbwindow.h index f98cd8a74d..8258cc2dfa 100644 --- a/src/plugins/platforms/xcb/qxcbwindow.h +++ b/src/plugins/platforms/xcb/qxcbwindow.h @@ -184,6 +184,9 @@ public: static void setWindowTitle(const QXcbConnection *conn, xcb_window_t window, const QString &title); static QString windowTitle(const QXcbConnection *conn, xcb_window_t window); + int swapInterval() const { return m_swapInterval; } + void setSwapInterval(int swapInterval) { m_swapInterval = swapInterval; } + public Q_SLOTS: void updateSyncRequestCounter(); @@ -276,6 +279,7 @@ protected: SyncState m_syncState = NoSyncNeeded; QXcbSyncWindowRequest *m_pendingSyncRequest = nullptr; + int m_swapInterval = -1; }; class QXcbForeignWindow : public QXcbWindow -- cgit v1.2.1