win32: minor refactor

Signed-off-by: Yuhang Zhao <2546789017@qq.com>

framelesshelper_win32.cpp

@@ -381,76 +381,7 @@ bool FramelessHelperWin::nativeEventFilter(const QByteArray &eventType, void *me
         // is not correct. It confuses QPA's internal logic.
         clientRect->bottom += 1;
 #endif
-        if (Utilities::isDwmCompositionAvailable()) {
+        Utilities::syncWmPaintWithDwm();
-            QSystemLibrary winmmLib(QStringLiteral("winmm"));
-            static const auto ptimeGetDevCaps =
-                reinterpret_cast</*MMRESULT*/UINT(WINAPI *)(flh_LPTIMECAPS, UINT)>(winmmLib.resolve("timeGetDevCaps"));
-            static const auto ptimeBeginPeriod =
-                reinterpret_cast</*MMRESULT*/UINT(WINAPI *)(UINT)>(winmmLib.resolve("timeBeginPeriod"));
-            static const auto ptimeEndPeriod =
-                reinterpret_cast</*MMRESULT*/UINT(WINAPI *)(UINT)>(winmmLib.resolve("timeEndPeriod"));
-            static const auto pDwmGetCompositionTimingInfo =
-                reinterpret_cast<HRESULT(WINAPI *)(HWND, DWM_TIMING_INFO *)>(QSystemLibrary::resolve(QStringLiteral("dwmapi"), "DwmGetCompositionTimingInfo"));
-            if (ptimeGetDevCaps && ptimeBeginPeriod && ptimeEndPeriod && pDwmGetCompositionTimingInfo) {
-                // Dirty hack to workaround the resize flicker caused by DWM.
-                LARGE_INTEGER freq = {};
-                if (QueryPerformanceFrequency(&freq) == FALSE) {
-                    qWarning() << Utilities::getSystemErrorMessage(QStringLiteral("QueryPerformanceFrequency"));
-                    break;
-                }
-                flh_TIMECAPS tc = {};
-                if (ptimeGetDevCaps(&tc, sizeof(tc)) != /*MMSYSERR_NOERROR*/0) {
-                    qWarning() << "timeGetDevCaps() failed.";
-                    break;
-                }
-                const UINT ms_granularity = tc.wPeriodMin;
-                if (ptimeBeginPeriod(ms_granularity) != /*TIMERR_NOERROR*/0) {
-                    qWarning() << "timeBeginPeriod() failed.";
-                    break;
-                }
-                LARGE_INTEGER now0 = {};
-                if (QueryPerformanceCounter(&now0) == FALSE) {
-                    qWarning() << Utilities::getSystemErrorMessage(QStringLiteral("QueryPerformanceCounter"));
-                    break;
-                }
-                // ask DWM where the vertical blank falls
-                DWM_TIMING_INFO dti;
-                SecureZeroMemory(&dti, sizeof(dti));
-                dti.cbSize = sizeof(dti);
-                const HRESULT hr = pDwmGetCompositionTimingInfo(nullptr, &dti);
-                if (FAILED(hr)) {
-                    qWarning() << Utilities::getSystemErrorMessage(QStringLiteral("DwmGetCompositionTimingInfo"));
-                    break;
-                }
-                LARGE_INTEGER now1 = {};
-                if (QueryPerformanceCounter(&now1) == FALSE) {
-                    qWarning() << Utilities::getSystemErrorMessage(QStringLiteral("QueryPerformanceCounter"));
-                    break;
-                }
-                // - DWM told us about SOME vertical blank
-                //   - past or future, possibly many frames away
-                // - convert that into the NEXT vertical blank
-                const LONGLONG period = dti.qpcRefreshPeriod;
-                const LONGLONG dt = dti.qpcVBlank - now1.QuadPart;
-                LONGLONG w = 0, m = 0;
-                if (dt >= 0) {
-                    w = dt / period;
-                } else {
-                    // reach back to previous period
-                    // - so m represents consistent position within phase
-                    w = -1 + dt / period;
-                }
-                m = dt - (period * w);
-                Q_ASSERT(m >= 0);
-                Q_ASSERT(m < period);
-                const qreal m_ms = 1000.0 * static_cast<qreal>(m) / static_cast<qreal>(freq.QuadPart);
-                Sleep(static_cast<DWORD>(qRound(m_ms)));
-                if (ptimeEndPeriod(ms_granularity) != /*TIMERR_NOERROR*/0) {
-                    qWarning() << "timeEndPeriod() failed.";
-                    break;
-                }
-            }
-        }
         // We cannot return WVR_REDRAW otherwise Windows exhibits bugs where
         // client pixels and child windows are mispositioned by the width/height
         // of the upper-left nonclient area.
@@ -681,6 +612,9 @@ bool FramelessHelperWin::nativeEventFilter(const QByteArray &eventType, void *me
         Utilities::updateQtFrameMargins(const_cast<QWindow *>(window), true);
         Utilities::triggerFrameChange(reinterpret_cast<WId>(msg->hwnd));
     } break;
+    case WM_DWMCOMPOSITIONCHANGED: {
+        Utilities::updateFrameMargins(reinterpret_cast<WId>(msg->hwnd), false);
+    } break;
     default:
         break;
     }

framelesshelper_windows.h

@@ -86,6 +86,10 @@
 #define WM_NCUAHDRAWFRAME (0x00AF)
 #endif
 
+#ifndef WM_DWMCOMPOSITIONCHANGED
+#define WM_DWMCOMPOSITIONCHANGED (0x031E)
+#endif
+
 #ifndef WM_DWMCOLORIZATIONCOLORCHANGED
 #define WM_DWMCOLORIZATIONCOLORCHANGED (0x0320)
 #endif

utilities.h

@@ -57,6 +57,7 @@ FRAMELESSHELPER_API void updateQtFrameMargins(QWindow *window, const bool enable
 [[nodiscard]] FRAMELESSHELPER_API QString getSystemErrorMessage(const QString &function);
 [[nodiscard]] FRAMELESSHELPER_API bool isFullScreen(const WId winId);
 [[nodiscard]] FRAMELESSHELPER_API bool isWindowNoState(const WId winId);
+FRAMELESSHELPER_API void syncWmPaintWithDwm();
 #endif
 
 }

utilities_win32.cpp

@@ -593,4 +593,80 @@ bool Utilities::isWindowNoState(const WId winId)
     return ((wp.showCmd == SW_NORMAL) || (wp.showCmd == SW_RESTORE));
 }
 
+void Utilities::syncWmPaintWithDwm()
+{
+    // No need to sync with DWM if DWM composition is disabled.
+    if (!isDwmCompositionAvailable()) {
+        return;
+    }
+    QSystemLibrary winmmLib(QStringLiteral("winmm"));
+    static const auto ptimeGetDevCaps =
+        reinterpret_cast</*MMRESULT*/UINT(WINAPI *)(flh_LPTIMECAPS, UINT)>(winmmLib.resolve("timeGetDevCaps"));
+    static const auto ptimeBeginPeriod =
+        reinterpret_cast</*MMRESULT*/UINT(WINAPI *)(UINT)>(winmmLib.resolve("timeBeginPeriod"));
+    static const auto ptimeEndPeriod =
+        reinterpret_cast</*MMRESULT*/UINT(WINAPI *)(UINT)>(winmmLib.resolve("timeEndPeriod"));
+    static const auto pDwmGetCompositionTimingInfo =
+        reinterpret_cast<HRESULT(WINAPI *)(HWND, DWM_TIMING_INFO *)>(QSystemLibrary::resolve(QStringLiteral("dwmapi"), "DwmGetCompositionTimingInfo"));
+    if (!ptimeGetDevCaps || !ptimeBeginPeriod || !ptimeEndPeriod || !pDwmGetCompositionTimingInfo) {
+        return;
+    }
+    // Dirty hack to workaround the resize flicker caused by DWM.
+    LARGE_INTEGER freq = {};
+    if (QueryPerformanceFrequency(&freq) == FALSE) {
+        qWarning() << Utilities::getSystemErrorMessage(QStringLiteral("QueryPerformanceFrequency"));
+        return;
+    }
+    flh_TIMECAPS tc = {};
+    if (ptimeGetDevCaps(&tc, sizeof(tc)) != /*MMSYSERR_NOERROR*/0) {
+        qWarning() << "timeGetDevCaps() failed.";
+        return;
+    }
+    const UINT ms_granularity = tc.wPeriodMin;
+    if (ptimeBeginPeriod(ms_granularity) != /*TIMERR_NOERROR*/0) {
+        qWarning() << "timeBeginPeriod() failed.";
+        return;
+    }
+    LARGE_INTEGER now0 = {};
+    if (QueryPerformanceCounter(&now0) == FALSE) {
+        qWarning() << Utilities::getSystemErrorMessage(QStringLiteral("QueryPerformanceCounter"));
+        return;
+    }
+    // ask DWM where the vertical blank falls
+    DWM_TIMING_INFO dti;
+    SecureZeroMemory(&dti, sizeof(dti));
+    dti.cbSize = sizeof(dti);
+    const HRESULT hr = pDwmGetCompositionTimingInfo(nullptr, &dti);
+    if (FAILED(hr)) {
+        qWarning() << Utilities::getSystemErrorMessage(QStringLiteral("DwmGetCompositionTimingInfo"));
+        return;
+    }
+    LARGE_INTEGER now1 = {};
+    if (QueryPerformanceCounter(&now1) == FALSE) {
+        qWarning() << Utilities::getSystemErrorMessage(QStringLiteral("QueryPerformanceCounter"));
+        return;
+    }
+    // - DWM told us about SOME vertical blank
+    //   - past or future, possibly many frames away
+    // - convert that into the NEXT vertical blank
+    const LONGLONG period = dti.qpcRefreshPeriod;
+    const LONGLONG dt = dti.qpcVBlank - now1.QuadPart;
+    LONGLONG w = 0, m = 0;
+    if (dt >= 0) {
+        w = dt / period;
+    } else {
+        // reach back to previous period
+        // - so m represents consistent position within phase
+        w = -1 + dt / period;
+    }
+    m = dt - (period * w);
+    Q_ASSERT(m >= 0);
+    Q_ASSERT(m < period);
+    const qreal m_ms = 1000.0 * static_cast<qreal>(m) / static_cast<qreal>(freq.QuadPart);
+    Sleep(static_cast<DWORD>(qRound(m_ms)));
+    if (ptimeEndPeriod(ms_granularity) != /*TIMERR_NOERROR*/0) {
+        qWarning() << "timeEndPeriod() failed.";
+    }
+}
+
 FRAMELESSHELPER_END_NAMESPACE