From 3f0b8a9f198cd1e0e8ae9150561f93fb1b931b7e Mon Sep 17 00:00:00 2001 From: Paul Olav Tvete Date: Thu, 8 Jan 2015 13:55:32 +0100 Subject: [PATCH] Multi-screen DPI support for X11 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Calculate the logical DPI independently per screen, but only when auto dpr is enabled. Using a constant DPI value for all screens, based on the combined geometry is arguably incorrect, but changing this now will cause pixel-size fonts to behave visibly different from point-size fonts when moving the window to a different screen. However, with QT_DEVICE_PIXEL_RATIO=auto, the pixel size fonts are already changing when the devicePixelRatio changes. Without this change, the point-size fonts will *not* adapt, which is a clear bug. Task-number: QTBUG-43713 Change-Id: I3e71618f9d55b7828ccd70b69a7b7ce656c69d65 Reviewed-by: Friedemann Kleint Reviewed-by: Jørgen Lind Reviewed-by: Simon Hausmann Reviewed-by: Shawn Rutledge --- src/plugins/platforms/xcb/qxcbscreen.cpp | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/src/plugins/platforms/xcb/qxcbscreen.cpp b/src/plugins/platforms/xcb/qxcbscreen.cpp index f8d68c68f0..6559a0bdba 100644 --- a/src/plugins/platforms/xcb/qxcbscreen.cpp +++ b/src/plugins/platforms/xcb/qxcbscreen.cpp @@ -317,8 +317,14 @@ QDpi QXcbScreen::logicalDpi() const if (m_forcedDpi > 0) return QDpi(m_forcedDpi/dpr, m_forcedDpi/dpr); - return QDpi(Q_MM_PER_INCH * m_virtualSize.width() / m_virtualSizeMillimeters.width() / dpr, - Q_MM_PER_INCH * m_virtualSize.height() / m_virtualSizeMillimeters.height() / dpr); + static const bool auto_dpr = qgetenv("QT_DEVICE_PIXEL_RATIO").toLower() == "auto"; + if (auto_dpr) { + return QDpi(Q_MM_PER_INCH * m_geometry.width() / m_sizeMillimeters.width(), + Q_MM_PER_INCH * m_geometry.height() / m_sizeMillimeters.height()); + } else { + return QDpi(Q_MM_PER_INCH * m_virtualSize.width() / m_virtualSizeMillimeters.width() / dpr, + Q_MM_PER_INCH * m_virtualSize.height() / m_virtualSizeMillimeters.height() / dpr); + } }