HiDPI support implemented.

CMakeLists.txt

@@ -5,9 +5,9 @@ cmake_minimum_required(VERSION 3.0.0 FATAL_ERROR)
 set(CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/cmake/modules/")
 
 # Find the Qt5 libraries
-find_package(Qt5Core REQUIRED)
-find_package(Qt5Gui REQUIRED)
-find_package(Qt5Widgets REQUIRED)
+find_package(Qt5Core 5.14 REQUIRED)
+find_package(Qt5Gui 5.14 REQUIRED)
+find_package(Qt5Widgets 5.14 REQUIRED)
 
 option(USE_HARFBUZZ "Use HarfBuzz for text shaping" ON)
 option(BUILD_TESTS "Build test programs" OFF)

src/lowlevel_textrender.cpp

@@ -22,6 +22,7 @@
 #include "fc-lang-data.h"
 
 #include <QtGui/QPainter>
+#include <QtGui/QScreen>
 
 #include <QtCore/QDebug>
 
@@ -139,6 +140,8 @@ bool GLowLevelTextRender::renderText(const QString& text)
 bool GLowLevelTextRender::renderText()
 {
 	QSize sz = size();
+	qreal dpr = screen()->devicePixelRatio();
+	sz *= dpr;
 	if (sz.width() < 100 || sz.height() < 100)
 		return false;
 	if (!m_d->freetypeIsInited())
@@ -158,6 +161,7 @@ bool GLowLevelTextRender::renderText()
 	if (!m_offscreen)
 	{
 		m_offscreen = new QImage(sz.width(), sz.height(), QImage::Format_RGB32);
+		m_offscreen->setDevicePixelRatio(dpr);
 	}
 	m_offscreen->fill(m_backgroundColor);
 

src/mainwnd.cpp

@@ -20,6 +20,7 @@
 #include "ui_mainwnd.h"
 
 #include <QtGui/QShowEvent>
+#include <QtGui/QScreen>
 #include <QtWidgets/QFileDialog>
 #include <QtWidgets/QCheckBox>
 
@@ -41,6 +42,10 @@ GMainWindow::GMainWindow(QWidget *parent)
 	ui->fontLineEdit->setText("c:/Windows/Fonts/NotoSerif-Regular.ttf");
 #endif
 
+	qreal dpr = screen()->devicePixelRatio();
+	ui->fontSizeBox->setValue(ui->fontSizeBox->value()*dpr);
+	ui->fontSizeBox->setMaximum(ui->fontSizeBox->maximum()*dpr);
+
 	onFontChanged();
 }