Qt: HiDPI (retina) support for splash screen

- remove splash screen images (reduce binary size)
- dynamicly draw splash screen with available icon.
- remove testnet icon
- dynamicly colorize testnet icon

1 files changed, 34 insertions, 7 deletions

diff --git a/src/qt/splashscreen.cpp b/src/qt/splashscreen.cpp
index b4b81440ca..bfc69636bb 100644
--- a/src/qt/splashscreen.cpp
+++ b/src/qt/splashscreen.cpp
@@ -19,6 +19,7 @@
 #include <QCloseEvent>
 #include <QDesktopWidget>
 #include <QPainter>
+#include <QRadialGradient>
 
 SplashScreen::SplashScreen(Qt::WindowFlags f, const NetworkStyle *networkStyle) :
     QWidget(0, f), curAlignment(0)
@@ -30,6 +31,10 @@ SplashScreen::SplashScreen(Qt::WindowFlags f, const NetworkStyle *networkStyle)
     int titleCopyrightVSpace    = 40;
 
     float fontFactor            = 1.0;
+    float devicePixelRatio      = 1.0;
+#if QT_VERSION > 0x050100
+    devicePixelRatio = ((QGuiApplication*)QCoreApplication::instance())->devicePixelRatio();
+#endif
 
     // define text to place
     QString titleText       = tr("Bitcoin Core");
@@ -39,12 +44,34 @@ SplashScreen::SplashScreen(Qt::WindowFlags f, const NetworkStyle *networkStyle)
 
     QString font            = "Arial";
 
-    // load the bitmap for writing some text over it
-    pixmap     = networkStyle->getSplashImage();
+    // create a bitmap according to device pixelratio
+    QSize splashSize(480*devicePixelRatio,320*devicePixelRatio);
+    pixmap = QPixmap(splashSize);
+
+#if QT_VERSION > 0x050100
+    // change to HiDPI if it makes sense
+    pixmap.setDevicePixelRatio(devicePixelRatio);
+#endif
 
     QPainter pixPaint(&pixmap);
     pixPaint.setPen(QColor(100,100,100));
 
+    // draw a slighly radial gradient
+    QRadialGradient gradient(QPoint(0,0), splashSize.width()/devicePixelRatio);
+    gradient.setColorAt(0, Qt::white);
+    gradient.setColorAt(1, QColor(247,247,247));
+    QRect rGradient(QPoint(0,0), splashSize);
+    pixPaint.fillRect(rGradient, gradient);
+
+    // draw the bitcoin icon, expected size of PNG: 1024x1024
+    QRect rectIcon(QPoint(-150,-122), QSize(430,430));
+
+    const QSize requiredSize(1024,1024);
+    QIcon appIcon = networkStyle->getAppIcon(requiredSize);
+    QPixmap icon(appIcon.pixmap(requiredSize));
+
+    pixPaint.drawPixmap(rectIcon, icon);
+
     // check font size and drawing with
     pixPaint.setFont(QFont(font, 33*fontFactor));
     QFontMetrics fm = pixPaint.fontMetrics();
@@ -57,7 +84,7 @@ SplashScreen::SplashScreen(Qt::WindowFlags f, const NetworkStyle *networkStyle)
     pixPaint.setFont(QFont(font, 33*fontFactor));
     fm = pixPaint.fontMetrics();
     titleTextWidth  = fm.width(titleText);
-    pixPaint.drawText(pixmap.width()-titleTextWidth-paddingRight,paddingTop,titleText);
+    pixPaint.drawText(pixmap.width()/devicePixelRatio-titleTextWidth-paddingRight,paddingTop,titleText);
 
     pixPaint.setFont(QFont(font, 15*fontFactor));
 
@@ -68,11 +95,11 @@ SplashScreen::SplashScreen(Qt::WindowFlags f, const NetworkStyle *networkStyle)
         pixPaint.setFont(QFont(font, 10*fontFactor));
         titleVersionVSpace -= 5;
     }
-    pixPaint.drawText(pixmap.width()-titleTextWidth-paddingRight+2,paddingTop+titleVersionVSpace,versionText);
+    pixPaint.drawText(pixmap.width()/devicePixelRatio-titleTextWidth-paddingRight+2,paddingTop+titleVersionVSpace,versionText);
 
     // draw copyright stuff
     pixPaint.setFont(QFont(font, 10*fontFactor));
-    pixPaint.drawText(pixmap.width()-titleTextWidth-paddingRight,paddingTop+titleCopyrightVSpace,copyrightText);
+    pixPaint.drawText(pixmap.width()/devicePixelRatio-titleTextWidth-paddingRight,paddingTop+titleCopyrightVSpace,copyrightText);
 
     // draw additional text if special network
     if(!titleAddText.isEmpty()) {
@@ -81,7 +108,7 @@ SplashScreen::SplashScreen(Qt::WindowFlags f, const NetworkStyle *networkStyle)
         pixPaint.setFont(boldFont);
         fm = pixPaint.fontMetrics();
         int titleAddTextWidth  = fm.width(titleAddText);
-        pixPaint.drawText(pixmap.width()-titleAddTextWidth-10,15,titleAddText);
+        pixPaint.drawText(pixmap.width()/devicePixelRatio-titleAddTextWidth-10,15,titleAddText);
     }
 
     pixPaint.end();
@@ -90,7 +117,7 @@ SplashScreen::SplashScreen(Qt::WindowFlags f, const NetworkStyle *networkStyle)
     setWindowTitle(titleText + " " + titleAddText);
 
     // Resize window and move to center of desktop, disallow resizing
-    QRect r(QPoint(), pixmap.size());
+    QRect r(QPoint(), QSize(pixmap.size().width()/devicePixelRatio,pixmap.size().height()/devicePixelRatio));
     resize(r.size());
     setFixedSize(r.size());
     move(QApplication::desktop()->screenGeometry().center() - r.center());