diff options
| author | Samuel Rødal <samuel.rodal@nokia.com> | 2012-03-01 18:06:29 +0100 |
|---|---|---|
| committer | Qt by Nokia <qt-info@nokia.com> | 2012-03-02 15:55:44 +0100 |
| commit | ad1b5495a2a437d21435a9c321c9abf612cd210e (patch) | |
| tree | 42f4d4bf3669ce9727dc59ffc0eb7127e545e6be | |
| parent | 6f3fe3fee31697d8e828b0f88e9111bfbbb62490 (diff) | |
Fixed Windows performance regression introduced by ac2818bef95f134.
Only create a temporary DC if we're not on the main thread.
Task-number: QTBUG-24602
Change-Id: I36dad4c197c7cc1e019b19d42c81526fc8cfdcf4
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@nokia.com>
| -rw-r--r-- | src/gui/kernel/qwidget_win.cpp | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/src/gui/kernel/qwidget_win.cpp b/src/gui/kernel/qwidget_win.cpp index 3fdc00c834..8a400cded2 100644 --- a/src/gui/kernel/qwidget_win.cpp +++ b/src/gui/kernel/qwidget_win.cpp @@ -49,6 +49,7 @@ #include "qlayout.h" #include "qpainter.h" #include "qstack.h" +#include "qthread.h" #include "qt_windows.h" #include "qwidget.h" #include "qwidget_p.h" @@ -1636,6 +1637,8 @@ void QWidgetPrivate::scroll_sys(int dx, int dy, const QRect &r) } } +extern Q_GUI_EXPORT HDC qt_win_display_dc(); + int QWidget::metric(PaintDeviceMetric m) const { Q_D(const QWidget); @@ -1645,7 +1648,8 @@ int QWidget::metric(PaintDeviceMetric m) const } else if (m == PdmHeight) { val = data->crect.height(); } else { - HDC gdc = GetDC(0); + bool ownDC = QThread::currentThread() != qApp->thread(); + HDC gdc = ownDC ? GetDC(0) : qt_win_display_dc(); switch (m) { case PdmDpiX: case PdmPhysicalDpiX: @@ -1696,7 +1700,8 @@ int QWidget::metric(PaintDeviceMetric m) const val = 0; qWarning("QWidget::metric: Invalid metric command"); } - ReleaseDC(0, gdc); + if (ownDC) + ReleaseDC(0, gdc); } return val; } |