qt6windows7/tests/manual/highdpi/dprgadget/main.cpp
2023-10-29 23:33:08 +01:00

261 lines
9.9 KiB
C++

// Copyright (C) 2020 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
#include <QtCore/qtversion.h>
#include <QtGui/qpa/qplatformscreen.h>
#include <QtGui/qpa/qplatformwindow.h>
#include <QtGui/private/qhighdpiscaling_p.h>
#include <QtWidgets/QtWidgets>
#include <iostream>
/*
DprGadget: The focused High-DPI settings debug utility
DprGadget displays the device pixel ratio ("DPR") for the screen
it's on in a large font, as well as the inputs (from the platform
plugin or environment) currently in use for determinging the DPR.
Non-relevant inputs are not displayed. See qttools/src/qtdiag for
an utility which displays all inputs.
*/
bool g_qtScaleFactor = false;
bool g_qtUsePhysicalDpi = false;
bool g_qtFontDpi = false;
bool g_qtScaleFactorRoundingPolicy = false;
bool g_qtHighDpiDownscale = false;
bool g_displayEvents = false;
class DprGadget : public QWidget
{
public:
std::function<void(void)> m_clearFn;
std::function<void(void)> m_updateFn;
qreal m_currentDpr = -1;
QString m_eventsText;
DprGadget() {
setWindowTitle(QString("DprGadget - Qt %1").arg(qVersion()));
QFont tinyFont;
tinyFont.setPointSize(8);
QFont smallFont;
smallFont.setPointSize(12);
QFont bigFont;
bigFont.setPointSize(42);
QFont biggerFont;
biggerFont.setPointSize(80);
QLabel *dprLabel = new QLabel("Device Pixel Ratio");
dprLabel->setFont(bigFont);
dprLabel->setTextInteractionFlags(Qt::TextSelectableByMouse);
QLabel *dprValue = new QLabel();
dprValue->setFont(biggerFont);
dprValue->setTextInteractionFlags(Qt::TextSelectableByMouse);
QLabel *screenLabel = new QLabel("Current Screen:");
screenLabel->setFont(smallFont);
QLabel *sizeLabel = new QLabel("Window size:");
sizeLabel->setFont(smallFont);
sizeLabel->setTextInteractionFlags(Qt::TextSelectableByMouse);
QLabel *nativeSizeLabel = new QLabel("Native:");
nativeSizeLabel->setFont(smallFont);
nativeSizeLabel->setTextInteractionFlags(Qt::TextSelectableByMouse);
QLabel *dpiLabel = new QLabel("Logical DPI:");
dpiLabel->setFont(smallFont);
dpiLabel->setTextInteractionFlags(Qt::TextSelectableByMouse);
QLabel *windowDpiLabel = new QLabel("Window DPI:");
windowDpiLabel->setFont(smallFont);
windowDpiLabel->setTextInteractionFlags(Qt::TextSelectableByMouse);
QLabel *platformDpiLabel = new QLabel("Native Device Pixel Ratio:");
platformDpiLabel->setFont(smallFont);
platformDpiLabel->setTextInteractionFlags(Qt::TextSelectableByMouse);
QLabel *windowDprLabel = new QLabel("Window DPR:");
windowDprLabel->setFont(smallFont);
windowDprLabel->setTextInteractionFlags(Qt::TextSelectableByMouse);
QLabel *plarformDprLabel = new QLabel("Native DPI:");
plarformDprLabel->setFont(smallFont);
plarformDprLabel->setTextInteractionFlags(Qt::TextSelectableByMouse);
QLabel *qtScaleFactorLabel = new QLabel("Qt Internal Scale Factor:");
qtScaleFactorLabel->setFont(smallFont);
QLabel *eventsLabel = new QLabel(m_eventsText);
eventsLabel->setFont(tinyFont);
eventsLabel->setTextInteractionFlags(Qt::TextSelectableByMouse);
QVBoxLayout *layout = new QVBoxLayout();
layout->addWidget(dprLabel);
layout->setAlignment(dprLabel, Qt::AlignHCenter);
layout->addWidget(dprValue);
layout->setAlignment(dprValue, Qt::AlignHCenter);
bool displayLogicalDpi = false;
if (displayLogicalDpi)
layout->addWidget(dpiLabel);
layout->addStretch();
QHBoxLayout *screenLabelLayout = new QHBoxLayout();
screenLabelLayout->addStretch();
screenLabelLayout->addWidget(screenLabel);
screenLabelLayout->addStretch();
layout->addLayout(screenLabelLayout);
QHBoxLayout *windowSizeLayout = new QHBoxLayout();
windowSizeLayout->addWidget(sizeLabel);
windowSizeLayout->addStretch();
windowSizeLayout->addWidget(nativeSizeLabel);
layout->addLayout(windowSizeLayout);
QHBoxLayout *dpiLayout = new QHBoxLayout();
dpiLayout->addWidget(windowDpiLabel);
dpiLayout->addStretch();
dpiLayout->addWidget(platformDpiLabel);
layout->addLayout(dpiLayout);
QHBoxLayout *dprLayout = new QHBoxLayout();
dprLayout->addWidget(windowDprLabel);
dprLayout->addStretch();
dprLayout->addWidget(plarformDprLabel);
layout->addLayout(dprLayout);
QHBoxLayout *qtScaleFactorLabelLayout = new QHBoxLayout();
qtScaleFactorLabelLayout->addStretch();
qtScaleFactorLabelLayout->addWidget(qtScaleFactorLabel);
qtScaleFactorLabelLayout->addStretch();
layout->addLayout(qtScaleFactorLabelLayout);
if (g_displayEvents)
layout->addWidget(eventsLabel);
bool activeEnvironment = g_qtScaleFactor || g_qtUsePhysicalDpi || g_qtFontDpi || g_qtScaleFactorRoundingPolicy || g_qtHighDpiDownscale;
if (activeEnvironment) {
layout->addWidget(new QLabel("Active Environment:"));
if (g_qtScaleFactor) {
QString text = QString("QT_SCALE_FACTOR=") + qgetenv("QT_SCALE_FACTOR");
layout->addWidget(new QLabel(text));
}
if (g_qtUsePhysicalDpi) {
QString text = QString("QT_USE_PHYSICAL_DPI=") + qgetenv("QT_USE_PHYSICAL_DPI");
layout->addWidget(new QLabel(text));
}
if (g_qtFontDpi) {
QString text = QString("QT_FONT_DPI=") + qgetenv("QT_FONT_DPI");
layout->addWidget(new QLabel(text));
}
if (g_qtScaleFactorRoundingPolicy) {
QString text = QString("QT_SCALE_FACTOR_ROUNDING_POLICY=") + qgetenv("QT_SCALE_FACTOR_ROUNDING_POLICY");
layout->addWidget(new QLabel(text));
}
if (g_qtHighDpiDownscale) {
QString text = QString("QT_WIDGETS_HIGHDPI_DOWNSCALE=") + qgetenv("QT_WIDGETS_HIGHDPI_DOWNSCALE");
layout->addWidget(new QLabel(text));
}
}
auto updateValues = [=]() {
dprValue->setText(QString("%1").arg(devicePixelRatioF()));
windowDpiLabel->setText(QString("QWindow DPI: %1").arg(logicalDpiX()));
dpiLabel->setText(QString("Logical DPI: %1").arg(logicalDpiX()));
sizeLabel->setText(QString("QWindow size: %1 %2").arg(width()).arg(height()));
QPlatformWindow *platformWindow = windowHandle()->handle();
nativeSizeLabel->setText(QString("native size %1 %2").arg(platformWindow->geometry().width())
.arg(platformWindow->geometry().height()));
QPlatformScreen *pscreen = screen()->handle();
if (g_qtUsePhysicalDpi) {
int physicalDpi = qRound(pscreen->geometry().width() / pscreen->physicalSize().width() * qreal(25.4));
platformDpiLabel->setText(QString("Native Physical DPI: %1").arg(physicalDpi));
} else {
platformDpiLabel->setText(QString("native logical DPI: %1").arg(pscreen->logicalDpi().first));
}
windowDprLabel->setText(QString("QWindow DPR: %1").arg(windowHandle()->devicePixelRatio()));
plarformDprLabel->setText(QString("native DPR: %1").arg(pscreen->devicePixelRatio()));
screenLabel->setText(QString("Current Screen: %1").arg(screen()->name()));
qtScaleFactorLabel->setText(QString("Qt Internal Scale Factor: %1").arg(QHighDpiScaling::factor(windowHandle())));
eventsLabel->setText(QString(m_eventsText));
};
m_updateFn = updateValues;
m_clearFn = [=]() {
dprValue->setText(QString(""));
m_eventsText.clear();
};
create();
QObject::connect(this->windowHandle(), &QWindow::screenChanged, [updateValues, this](QScreen *screen){
Q_UNUSED(screen);
this->m_eventsText.prepend(QString("ScreenChange "));
this->m_eventsText.truncate(80);
updateValues();
});
setLayout(layout);
updateValues();
}
void paintEvent(QPaintEvent *) override {
// Update the UI in the paint event - normally not good
// practice but it looks like we can get away with it here
this->m_eventsText.prepend(QString("Paint "));
this->m_eventsText.truncate(80);
// Dpr change should trigger a repaint, update display values here
if (m_currentDpr == devicePixelRatioF())
return;
m_currentDpr = devicePixelRatioF();
m_updateFn();
}
void resizeEvent(QResizeEvent *event) override {
QSize size = event->size();
m_eventsText.prepend(QString("Resize(%1 %2) ").arg(size.width()).arg(size.height()));
m_eventsText.truncate(80);
m_updateFn();
}
void mousePressEvent(QMouseEvent *) override {
m_clearFn();
QTimer::singleShot(500, this, [this](){
m_updateFn();
});
}
};
int main(int argc, char **argv) {
// Set sensible defaults
QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
QGuiApplication::setHighDpiScaleFactorRoundingPolicy(Qt::HighDpiScaleFactorRoundingPolicy::PassThrough);
// Display any set high-dpi eviornment variable.
g_qtScaleFactor = qEnvironmentVariableIsSet("QT_SCALE_FACTOR");
g_qtUsePhysicalDpi = qgetenv("QT_USE_PHYSICAL_DPI") == QByteArray("1");
g_qtFontDpi = qEnvironmentVariableIsSet("QT_FONT_DPI");
g_qtScaleFactorRoundingPolicy = qEnvironmentVariableIsSet("QT_SCALE_FACTOR_ROUNDING_POLICY");
g_qtHighDpiDownscale = qEnvironmentVariableIsSet("QT_WIDGETS_HIGHDPI_DOWNSCALE");
QApplication app(argc, argv);
DprGadget dprGadget;
dprGadget.show();
return app.exec();
}