Fix some Quarter High DPI Display issues. Ported from code by Randall O'Reilly.

https://grey.colorado.edu/svn/coin3d/quarter/trunk/

src/Gui/Quarter/EventFilter.cpp

@@ -48,6 +48,10 @@
 #include <Quarter/devices/Keyboard.h>
 #include <Quarter/devices/SpaceNavigatorDevice.h>
 
+#if QT_VERSION >= 0x050000
+#include <QGuiApplication>
+#endif
+
 namespace SIM { namespace Coin3D { namespace Quarter {
 
 class EventFilterP {
@@ -73,11 +77,17 @@ public:
     this->globalmousepos = event->globalPos();
 
     SbVec2s mousepos(event->pos().x(), this->windowsize[1] - event->pos().y() - 1);
+    // the following corrects for high-dpi displays (e.g. mac retina)
+#if QT_VERSION >= 0x050000
+    mousepos *= ((QGuiApplication*)QGuiApplication::instance())->devicePixelRatio();
+#endif
     foreach(InputDevice * device, this->devices) {
       device->setMousePosition(mousepos);
     }
   }
 
+private:
+  qreal device_pixel_ratio = 1.0;
 };
 
 #define PRIVATE(obj) obj->pimpl

src/Gui/Quarter/Mouse.cpp

@@ -48,6 +48,10 @@
 #include <QtGui/QMouseEvent>
 #include <QtGui/QWheelEvent>
 
+#if QT_VERSION >= 0x050000
+#include <QGuiApplication>
+#endif
+
 #include <Inventor/SbVec2s.h>
 #include <Inventor/events/SoEvents.h>
 #include <Inventor/errors/SoDebugError.h>
@@ -136,6 +140,10 @@ MouseP::mouseMoveEvent(QMouseEvent * event)
 
   assert(this->windowsize[1] != -1);
   SbVec2s pos(event->pos().x(), this->windowsize[1] - event->pos().y() - 1);
+  // the following corrects for high-dpi displays (e.g. mac retina)
+#if QT_VERSION >= 0x050000
+  pos *= ((QGuiApplication*)QGuiApplication::instance())->devicePixelRatio();
+#endif
   this->location2->setPosition(pos);
   this->mousebutton->setPosition(pos);
   return this->location2;
@@ -146,6 +154,10 @@ MouseP::mouseWheelEvent(QWheelEvent * event)
 {
   PUBLIC(this)->setModifiers(this->mousebutton, event);
   SbVec2s pos(event->pos().x(), PUBLIC(this)->windowsize[1] - event->pos().y() - 1);
+  // the following corrects for high-dpi displays (e.g. mac retina)
+#if QT_VERSION >= 0x050000
+  pos *= ((QGuiApplication*)QGuiApplication::instance())->devicePixelRatio();
+#endif
   this->location2->setPosition(pos);
   this->mousebutton->setPosition(pos);
 
@@ -167,6 +179,10 @@ MouseP::mouseButtonEvent(QMouseEvent * event)
 {
   PUBLIC(this)->setModifiers(this->mousebutton, event);
   SbVec2s pos(event->pos().x(), PUBLIC(this)->windowsize[1] - event->pos().y() - 1);
+  // the following corrects for high-dpi displays (e.g. mac retina)
+#if QT_VERSION >= 0x050000
+  pos *= ((QGuiApplication*)QGuiApplication::instance())->devicePixelRatio();
+#endif
   this->location2->setPosition(pos);
   this->mousebutton->setPosition(pos);
 

src/Gui/Quarter/QuarterWidget.cpp

@@ -89,6 +89,12 @@
 #include "QuarterWidgetP.h"
 #include "QuarterP.h"
 
+#if QT_VERSION >= 0x050000
+#include <QWindow>
+#include <QGuiApplication>
+#endif
+
+
 using namespace SIM::Coin3D::Quarter;
 
 /*!
@@ -488,6 +494,23 @@ QuarterWidget::stereoMode(void) const
   return static_cast<StereoMode>(PRIVATE(this)->sorendermanager->getStereoMode());
 }
 
+/*!
+  \property QuarterWidget::devicePixelRatio
+
+  \copydetails QuarterWidget::devicePixelRatio
+*/
+
+/*!
+  The ratio between logical and physical pixel sizes -- obtained from the window that
+the widget is located within, and updated whenver any change occurs, emitting a devicePixelRatioChanged signal.  Only available for version Qt 5.6 and above (will be 1.0 for all previous versions)
+ */
+
+qreal
+QuarterWidget::devicePixelRatio(void) const
+{
+  return PRIVATE(this)->device_pixel_ratio;
+}
+
 /*!
   Sets the Inventor scenegraph to be rendered
  */
@@ -675,12 +698,42 @@ QuarterWidget::seek(void)
     }
   }
 }
+
+bool
+QuarterWidget::updateDevicePixelRatio(void) {
+#if QT_VERSION >= 0x050000
+    qreal dev_pix_ratio = 1.0;
+    QWidget* winwidg = window();
+    QWindow* win = NULL;
+    if(winwidg) {
+        win = winwidg->windowHandle();
+    }
+    if(win) {
+        dev_pix_ratio = win->devicePixelRatio();
+    }
+    else {
+        dev_pix_ratio = ((QGuiApplication*)QGuiApplication::instance())->devicePixelRatio();
+    }
+    if(PRIVATE(this)->device_pixel_ratio != dev_pix_ratio) {
+        PRIVATE(this)->device_pixel_ratio = dev_pix_ratio;
+        emit devicePixelRatioChanged(dev_pix_ratio);
+        return true;
+    }
+#endif
+    return false;
+}
+
 /*!
   Overridden from QGLWidget to resize the Coin scenegraph
  */
 void QuarterWidget::resizeEvent(QResizeEvent* event)
 {
-    SbViewportRegion vp(event->size().width(), event->size().height());
+    updateDevicePixelRatio();
+    qreal dev_pix_ratio = devicePixelRatio();
+    int width = static_cast<int>(dev_pix_ratio * event->size().width());
+    int height = static_cast<int>(dev_pix_ratio * event->size().height());
+
+    SbViewportRegion vp(width, height);
     PRIVATE(this)->sorendermanager->setViewportRegion(vp);
     PRIVATE(this)->soeventmanager->setViewportRegion(vp);
     if (scene())

src/Gui/Quarter/QuarterWidget.h

@@ -73,6 +73,7 @@ class QUARTER_DLL_API QuarterWidget : public QGraphicsView {
   Q_PROPERTY(TransparencyType transparencyType READ transparencyType WRITE setTransparencyType)
   Q_PROPERTY(RenderMode renderMode READ renderMode WRITE setRenderMode)
   Q_PROPERTY(StereoMode stereoMode READ stereoMode WRITE setStereoMode)
+  Q_PROPERTY(qreal devicePixelRatio READ devicePixelRatio NOTIFY devicePixelRatioChanged)
 
   Q_ENUMS(TransparencyType)
   Q_ENUMS(RenderMode)
@@ -123,6 +124,8 @@ public:
   void setBackgroundColor(const QColor & color);
   QColor backgroundColor(void) const;
 
+  qreal devicePixelRatio(void) const;
+
   void resetNavigationModeFile(void);
   void setNavigationModeFile(const QUrl & url = QUrl(QString::fromLatin1(DEFAULT_NAVIGATIONFILE)));
   const QUrl & navigationModeFile(void) const;
@@ -183,12 +186,16 @@ public Q_SLOTS:
   void setStereoMode(StereoMode mode);
   void setTransparencyType(TransparencyType type);
 
+Q_SIGNALS:
+  void devicePixelRatioChanged(qreal dev_pixel_ratio);
+
 protected:
   virtual void paintEvent(QPaintEvent*);
   virtual void resizeEvent(QResizeEvent*);
   virtual bool viewportEvent(QEvent* event);
   virtual void actualRedraw(void);
-  
+  virtual bool updateDevicePixelRatio(void);
+
   double renderTime;
 
 private:

src/Gui/Quarter/QuarterWidgetP.cpp

@@ -86,7 +86,8 @@ QuarterWidgetP::QuarterWidgetP(QuarterWidget * masterptr, const QGLWidget * shar
   clearzbuffer(true),
   clearwindow(true),
   addactions(true),
-  contextmenu(NULL)
+  contextmenu(NULL),
+  device_pixel_ratio(1.0)
 {
   this->cachecontext = findCacheContext(masterptr, sharewidget);
 

src/Gui/Quarter/QuarterWidgetP.h

@@ -92,6 +92,7 @@ public:
   bool processdelayqueue;
   QUrl navigationModeFile;
   SoScXMLStateMachine * currentStateMachine;
+  qreal device_pixel_ratio;
 
   static void rendercb(void * userdata, SoRenderManager *);
   static void prerendercb(void * userdata, SoRenderManager * manager);