From dd52fd0024600d3beffc82d6da02b4239a62d725 Mon Sep 17 00:00:00 2001 From: Jocelyn Turcotte Date: Tue, 17 Jan 2017 17:05:00 +0100 Subject: [PATCH] Ensure a pixel density of at least 1 for Qt::AA_EnableHighDpiScaling Very large 1080p TVs or any display which is running at an abnormally low resolution can have a DPI lower than 48, which means that qRound(dpi/96) will result in a 0 pixel density, causing critical issues for applications using Qt::AA_EnableHighDpiScaling. Make sure that we always have a pixel density of at least 1 to allow applications not having to worry about such displays. Task-number: QTBUG-56140 Change-Id: I1dafbf7794a99ae6f872984c0337d8ff0d1fc1c0 Reviewed-by: Shawn Rutledge Reviewed-by: Friedemann Kleint --- src/plugins/platforms/eglfs/api/qeglfsdeviceintegration.cpp | 2 +- src/plugins/platforms/windows/qwindowsscreen.cpp | 2 +- src/plugins/platforms/winrt/qwinrtscreen.cpp | 2 +- src/plugins/platforms/xcb/qxcbscreen.cpp | 2 +- 4 files changed, 4 insertions(+), 4 deletions(-) diff --git a/src/plugins/platforms/eglfs/api/qeglfsdeviceintegration.cpp b/src/plugins/platforms/eglfs/api/qeglfsdeviceintegration.cpp index 3e1e93f1e4..863a115b74 100644 --- a/src/plugins/platforms/eglfs/api/qeglfsdeviceintegration.cpp +++ b/src/plugins/platforms/eglfs/api/qeglfsdeviceintegration.cpp @@ -226,7 +226,7 @@ QDpi QEglFSDeviceIntegration::logicalDpi() const qreal QEglFSDeviceIntegration::pixelDensity() const { - return qRound(logicalDpi().first / qreal(100)); + return qMax(1, qRound(logicalDpi().first / qreal(100))); } Qt::ScreenOrientation QEglFSDeviceIntegration::nativeOrientation() const diff --git a/src/plugins/platforms/windows/qwindowsscreen.cpp b/src/plugins/platforms/windows/qwindowsscreen.cpp index 7a885b462e..c70323c06f 100644 --- a/src/plugins/platforms/windows/qwindowsscreen.cpp +++ b/src/plugins/platforms/windows/qwindowsscreen.cpp @@ -265,7 +265,7 @@ qreal QWindowsScreen::pixelDensity() const // the pixel density since it is reflects the Windows UI scaling. // High DPI auto scaling should be disabled when the user chooses // small fonts on a High DPI monitor, resulting in lower logical DPI. - return qRound(logicalDpi().first / 96); + return qMax(1, qRound(logicalDpi().first / 96)); } /*! diff --git a/src/plugins/platforms/winrt/qwinrtscreen.cpp b/src/plugins/platforms/winrt/qwinrtscreen.cpp index f87ae9fd24..2a4b6c8907 100644 --- a/src/plugins/platforms/winrt/qwinrtscreen.cpp +++ b/src/plugins/platforms/winrt/qwinrtscreen.cpp @@ -647,7 +647,7 @@ QDpi QWinRTScreen::logicalDpi() const qreal QWinRTScreen::pixelDensity() const { Q_D(const QWinRTScreen); - return qRound(d->logicalDpi / 96); + return qMax(1, qRound(d->logicalDpi / 96)); } qreal QWinRTScreen::scaleFactor() const diff --git a/src/plugins/platforms/xcb/qxcbscreen.cpp b/src/plugins/platforms/xcb/qxcbscreen.cpp index a9675935f4..d8facdbb84 100644 --- a/src/plugins/platforms/xcb/qxcbscreen.cpp +++ b/src/plugins/platforms/xcb/qxcbscreen.cpp @@ -631,7 +631,7 @@ void QXcbScreen::updateGeometry(const QRect &geom, uint8_t rotation) m_sizeMillimeters = sizeInMillimeters(xGeometry.size(), virtualDpi()); qreal dpi = xGeometry.width() / physicalSize().width() * qreal(25.4); - m_pixelDensity = qRound(dpi/96); + m_pixelDensity = qMax(1, qRound(dpi/96)); m_geometry = QRect(xGeometry.topLeft(), xGeometry.size()); m_availableGeometry = xGeometry & m_virtualDesktop->workArea(); QWindowSystemInterface::handleScreenGeometryChange(QPlatformScreen::screen(), m_geometry, m_availableGeometry); -- 2.13.0