Add drag and zoom to gui

WangscapeGui/CMakeLists.txt

@@ -12,7 +12,7 @@ include_directories(${Qt5Widgets_INCLUDE_DIR})
 qt5_wrap_ui(UIS_HDRS MainWindow.ui OptionsEditor.ui)
 
 # Tell CMake to create the helloworld executable
-add_executable(WangscapeGui WIN32 Main.cpp MainWindow.cpp OptionsEditor.cpp ${UIS_HDRS})
+add_executable(WangscapeGui WIN32 Main.cpp MainWindow.cpp OptionsEditor.cpp CustomGraphicsView.cpp ${UIS_HDRS})
 
 # Use the Widgets module from Qt 5.
 target_link_libraries(WangscapeGui wangscape-main)

WangscapeGui/CustomGraphicsView.cpp

@@ -0,0 +1,29 @@
+#include "CustomGraphicsView.h"
+
+CustomGraphicsView::CustomGraphicsView(QWidget* parent) :
+    QGraphicsView(parent) {}
+
+CustomGraphicsView::CustomGraphicsView (QGraphicsScene* scene, QWidget* parent) :
+    QGraphicsView(scene, parent) {}
+
+void CustomGraphicsView::wheelEvent(QWheelEvent* event)
+{
+    static const double zoomInFactor = 1.5;
+    static const double zoomOutFactor = 1.0 / zoomInFactor;
+
+    if(event->modifiers() & Qt::ControlModifier)
+    {
+        QGraphicsView::wheelEvent(event);
+    }
+    else
+    {
+        if(event->delta() > 0)
+       {
+           scale(zoomInFactor, zoomInFactor);
+       }
+       else
+       {
+           scale(zoomOutFactor, zoomOutFactor);
+       }
+   }
+}

WangscapeGui/CustomGraphicsView.h

@@ -0,0 +1,17 @@
+#ifndef CUSTOMGRAPHICSVIEW_H
+#define CUSTOMGRAPHICSVIEW_H
+
+#include <QGraphicsView>
+#include <QWheelEvent>
+
+class CustomGraphicsView : public QGraphicsView
+{
+public:
+    CustomGraphicsView(QWidget* parent = 0);
+    CustomGraphicsView(QGraphicsScene* scene, QWidget* parent = 0);
+
+protected:
+    virtual void wheelEvent(QWheelEvent* event);
+};
+
+#endif // CUSTOMGRAPHICSVIEW_H

WangscapeGui/MainWindow.cpp

@@ -149,6 +149,8 @@ void MainWindow::loadOptionsFromFile()
     mUi->generateButton->setEnabled(true);
     mUi->saveButton->setEnabled(false);
 
+    mUi->tilesetPreview->setDragMode(QGraphicsView::ScrollHandDrag);
+
     mUi->comboBox->clear();
     mPreviewImages.clear();
     mScene->clear();

WangscapeGui/MainWindow.ui

@@ -118,7 +118,7 @@
      </layout>
     </item>
     <item>
-     <widget class="QGraphicsView" name="tilesetPreview"/>
+     <widget class="CustomGraphicsView" name="tilesetPreview"/>
     </item>
     <item>
      <widget class="QProgressBar" name="progressBar">
@@ -164,6 +164,13 @@
   </action>
  </widget>
  <layoutdefault spacing="6" margin="11"/>
+ <customwidgets>
+  <customwidget>
+   <class>CustomGraphicsView</class>
+   <extends>QGraphicsView</extends>
+   <header>CustomGraphicsView.h</header>
+  </customwidget>
+ </customwidgets>
  <resources/>
  <connections/>
 </ui>