File indexing completed on 2025-04-27 11:33:00

 /*
     SPDX-FileCopyrightText: 2020 Vlad Zahorodnii <vlad.zahorodnii@kde.org>
 
     SPDX-License-Identifier: GPL-2.0-or-later
 */
 
 #include "x11_standalone_omlsynccontrolvsyncmonitor.h"
 #include "x11_standalone_glxconvenience.h"
 #include "x11_standalone_logging.h"
 
 #if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
 #include <private/qtx11extras_p.h>
 #else
 #include <QX11Info>
 #endif
 
 namespace KWin
 {
 
 std::unique_ptr<OMLSyncControlVsyncMonitor> OMLSyncControlVsyncMonitor::create()
 {
     const char *extensions = glXQueryExtensionsString(QX11Info::display(),
                                                       QX11Info::appScreen());
     if (!strstr(extensions, "GLX_OML_sync_control")) {
         return nullptr; // GLX_OML_sync_control is unsupported.
     }
 
     std::unique_ptr<OMLSyncControlVsyncMonitor> monitor{new OMLSyncControlVsyncMonitor()};
     if (monitor->isValid()) {
         return monitor;
     } else {
         return nullptr;
     }
 }
 
 OMLSyncControlVsyncMonitorHelper::OMLSyncControlVsyncMonitorHelper()
 {
     // Establish a new X11 connection to avoid locking up the main X11 connection.
     m_display = XOpenDisplay(DisplayString(QX11Info::display()));
     if (!m_display) {
         qCDebug(KWIN_X11STANDALONE) << "Failed to establish vsync monitor X11 connection";
         return;
     }
 
     ::Window rootWindow = DefaultRootWindow(m_display);
 
     const int attribs[] = {
         GLX_RENDER_TYPE, GLX_RGBA_BIT,
         GLX_DRAWABLE_TYPE, GLX_WINDOW_BIT,
         0};
 
     GLXFBConfig config = chooseGlxFbConfig(m_display, attribs);
     if (!config) {
         qCDebug(KWIN_X11STANDALONE) << "Couldn't find any suitable FBConfig for vsync monitor";
         return;
     }
 
     XVisualInfo *visualInfo = glXGetVisualFromFBConfig(m_display, config);
     if (!visualInfo) {
         return;
     }
 
     Visual *visual = visualInfo->visual;
     const int depth = visualInfo->depth;
     XFree(visualInfo);
 
     Colormap colormap = XCreateColormap(m_display, rootWindow, visual, AllocNone);
     XSetWindowAttributes attributes;
     attributes.colormap = colormap;
 
     m_dummyWindow = XCreateWindow(m_display, rootWindow, 0, 0, 1, 1, 0, depth,
                                   InputOutput, visual, CWColormap, &attributes);
     XFreeColormap(m_display, colormap);
     if (!m_dummyWindow) {
         qCDebug(KWIN_X11STANDALONE) << "Failed to create a dummy window for vsync monitor";
         return;
     }
 
     m_drawable = glXCreateWindow(m_display, config, m_dummyWindow, nullptr);
     if (!m_drawable) {
         qCDebug(KWIN_X11STANDALONE) << "Failed to create GLXWindow for dummy window";
         return;
     }
 
     m_localContext = glXCreateNewContext(m_display, config, GLX_RGBA_TYPE, 0, true);
     if (!m_localContext) {
         qCDebug(KWIN_X11STANDALONE) << "Failed to create opengl context for vsync monitor";
         return;
     }
 }
 
 OMLSyncControlVsyncMonitorHelper::~OMLSyncControlVsyncMonitorHelper()
 {
     if (m_localContext) {
         glXDestroyContext(m_display, m_localContext);
     }
     if (m_drawable) {
         glXDestroyWindow(m_display, m_drawable);
     }
     if (m_dummyWindow) {
         XDestroyWindow(m_display, m_dummyWindow);
     }
     if (m_display) {
         XCloseDisplay(m_display);
     }
 }
 
 bool OMLSyncControlVsyncMonitorHelper::isValid() const
 {
     return m_display && m_localContext && m_drawable;
 }
 
 void OMLSyncControlVsyncMonitorHelper::poll()
 {
     if (!glXMakeCurrent(m_display, m_drawable, m_localContext)) {
         qCDebug(KWIN_X11STANDALONE) << "Failed to make vsync monitor OpenGL context current";
         return;
     }
 
     int64_t ust, msc, sbc;
 
     glXGetSyncValuesOML(m_display, m_drawable, &ust, &msc, &sbc);
     glXWaitForMscOML(m_display, m_drawable, 0, 2, (msc + 1) % 2, &ust, &msc, &sbc);
 
     Q_EMIT vblankOccurred(std::chrono::microseconds(ust));
 }
 
 OMLSyncControlVsyncMonitor::OMLSyncControlVsyncMonitor()
 {
     m_helper.moveToThread(&m_thread);
 
     connect(&m_helper, &OMLSyncControlVsyncMonitorHelper::errorOccurred,
             this, &OMLSyncControlVsyncMonitor::errorOccurred);
     connect(&m_helper, &OMLSyncControlVsyncMonitorHelper::vblankOccurred,
             this, &OMLSyncControlVsyncMonitor::vblankOccurred);
 
     m_thread.setObjectName(QStringLiteral("vsync event monitor"));
     m_thread.start();
 }
 
 OMLSyncControlVsyncMonitor::~OMLSyncControlVsyncMonitor()
 {
     m_thread.quit();
     m_thread.wait();
 }
 
 bool OMLSyncControlVsyncMonitor::isValid() const
 {
     return m_helper.isValid();
 }
 
 void OMLSyncControlVsyncMonitor::arm()
 {
     QMetaObject::invokeMethod(&m_helper, &OMLSyncControlVsyncMonitorHelper::poll);
 }
 
 } // namespace KWin