# ShareCameraQt

VTKExamples/Cxx/Qt/ShareCameraQt

### Code

ShareCameraQt.cxx

    #include "ShareCameraQt.h"

    #include <vtkCamera.h>
    #include <vtkCommand.h>
    #include <vtkCubeSource.h>
    #include <vtkDataObjectToTable.h>
    #include <vtkElevationFilter.h>
    #include <vtkGenericOpenGLRenderWindow.h>
    #include <vtkNamedColors.h>
    #include <vtkNew.h>
    #include <vtkPolyDataMapper.h>
    #include <vtkProperty.h>
    #include <vtkQtTableView.h>
    #include <vtkRenderWindow.h>
    #include <vtkRenderer.h>
    #include <vtkSmartPointer.h>
    #include <vtkSphereSource.h>

    // Constructor
    ShareCameraQt::ShareCameraQt() {
      this->setupUi(this);

      vtkNew<vtkNamedColors> colors;

      vtkNew<vtkGenericOpenGLRenderWindow> renderWindowLeft;
      this->qvtkWidgetLeft->SetRenderWindow(renderWindowLeft);
      vtkNew<vtkGenericOpenGLRenderWindow> renderWindowRight;
      this->qvtkWidgetRight->SetRenderWindow(renderWindowRight);

      // Sphere
      vtkSmartPointer<vtkSphereSource> sphereSource =
          vtkSmartPointer<vtkSphereSource>::New();
      sphereSource->Update();
      vtkSmartPointer<vtkPolyDataMapper> sphereMapper =
          vtkSmartPointer<vtkPolyDataMapper>::New();
      sphereMapper->SetInputConnection(sphereSource->GetOutputPort());
      vtkSmartPointer<vtkActor> sphereActor = vtkSmartPointer<vtkActor>::New();
      sphereActor->SetMapper(sphereMapper);
      sphereActor->GetProperty()->SetColor(colors->GetColor4d("Tomato").GetData());

      // Cube
      vtkSmartPointer<vtkCubeSource> cubeSource =
          vtkSmartPointer<vtkCubeSource>::New();
      cubeSource->Update();
      vtkSmartPointer<vtkPolyDataMapper> cubeMapper =
          vtkSmartPointer<vtkPolyDataMapper>::New();
      cubeMapper->SetInputConnection(cubeSource->GetOutputPort());
      vtkSmartPointer<vtkActor> cubeActor = vtkSmartPointer<vtkActor>::New();
      cubeActor->SetMapper(cubeMapper);
      cubeActor->GetProperty()->SetColor(
          colors->GetColor4d("MediumSeaGreen").GetData());

      // VTK Renderer
      vtkSmartPointer<vtkRenderer> leftRenderer =
          vtkSmartPointer<vtkRenderer>::New();
      leftRenderer->AddActor(sphereActor);
      leftRenderer->SetBackground(colors->GetColor3d("LightSteelBlue").GetData());

      vtkSmartPointer<vtkRenderer> rightRenderer =
          vtkSmartPointer<vtkRenderer>::New();

      // Add Actor to renderer
      rightRenderer->AddActor(cubeActor);
      rightRenderer->SetBackground(colors->GetColor3d("LightSteelBlue").GetData());

      // VTK/Qt wedded
      this->qvtkWidgetLeft->GetRenderWindow()->AddRenderer(leftRenderer);
      this->qvtkWidgetRight->GetRenderWindow()->AddRenderer(rightRenderer);

      rightRenderer->ResetCamera();
      leftRenderer->ResetCamera();

      // Here we share the camera
      rightRenderer->SetActiveCamera(leftRenderer->GetActiveCamera());

      // Position the cube using the left renderer active camera
      leftRenderer->GetActiveCamera()->SetPosition(1.0, 0.8, 1.0);
      leftRenderer->GetActiveCamera()->SetFocalPoint(0, 0, 0);
      leftRenderer->ResetCamera();
      leftRenderer->GetActiveCamera()->Zoom(0.8);

      // Set up action signals and slots
      connect(this->actionExit, SIGNAL(triggered()), this, SLOT(slotExit()));

      this->qvtkWidgetLeft->GetRenderWindow()->AddObserver(
          vtkCommand::ModifiedEvent, this, &ShareCameraQt::ModifiedHandler);
    }

    void ShareCameraQt::ModifiedHandler() {
      this->qvtkWidgetRight->GetRenderWindow()->Render();
    }

    void ShareCameraQt::slotExit() { qApp->exit(); }

ShareCameraQt.h

    #ifndef ShareCameraQt_H
    #define ShareCameraQt_H

    #include <QMainWindow>
    #include "ui_ShareCameraQt.h"

    class ShareCameraQt : public QMainWindow, public Ui::ShareCameraQt
    {
      Q_OBJECT
    public:

      // Constructor/Destructor
      ShareCameraQt();
      ~ShareCameraQt() {};

    public slots:

      virtual void slotExit();

    protected:
       void ModifiedHandler();
    };

    #endif

ShareCameraQtDriver.cxx

    #include <QApplication>
    #include <QSurfaceFormat>
    #include <QVTKOpenGLNativeWidget.h>

    #include "ShareCameraQt.h"

    int main( int argc, char** argv )
    {
      // needed to ensure appropriate OpenGL context is created for VTK rendering.
      QSurfaceFormat::setDefaultFormat(QVTKOpenGLNativeWidget::defaultFormat());

      // QT Stuff
      QApplication app( argc, argv );

      ShareCameraQt shareCameraQt;
      shareCameraQt.show();

      return app.exec();
    }

ShareCameraQt.ui

    <?xml version="1.0" encoding="UTF-8"?>
    <ui version="4.0">
     <class>ShareCameraQt</class>
     <widget class="QMainWindow" name="ShareCameraQt">
      <property name="geometry">
       <rect>
        <x>0</x>
        <y>0</y>
        <width>990</width>
        <height>583</height>
       </rect>
      </property>
      <property name="windowTitle">
       <string>ShareCameraQt</string>
      </property>
      <property name="windowIcon">
       <iconset resource="Icons/icons.qrc">
        <normaloff>:/Icons/help.png</normaloff>:/Icons/help.png</iconset>
      </property>
      <property name="iconSize">
       <size>
        <width>22</width>
        <height>22</height>
       </size>
      </property>
      <widget class="QWidget" name="centralwidget">
       <widget class="QVTKOpenGLNativeWidget" name="qvtkWidgetLeft">
        <property name="geometry">
         <rect>
          <x>10</x>
          <y>20</y>
          <width>511</width>
          <height>541</height>
         </rect>
        </property>
       </widget>
       <widget class="QVTKOpenGLNativeWidget" name="qvtkWidgetRight">
        <property name="geometry">
         <rect>
          <x>540</x>
          <y>20</y>
          <width>441</width>
          <height>541</height>
         </rect>
        </property>
       </widget>
      </widget>
      <action name="actionOpenFile">
       <property name="enabled">
        <bool>true</bool>
       </property>
       <property name="icon">
        <iconset resource="Icons/icons.qrc">
         <normaloff>:/Icons/fileopen.png</normaloff>:/Icons/fileopen.png</iconset>
       </property>
       <property name="text">
        <string>Open File...</string>
       </property>
      </action>
      <action name="actionExit">
       <property name="icon">
        <iconset>
         <normaloff/>
        </iconset>
       </property>
       <property name="text">
        <string>Exit</string>
       </property>
      </action>
      <action name="actionPrint">
       <property name="icon">
        <iconset resource="Icons/icons.qrc">
         <normaloff>:/Icons/print.png</normaloff>:/Icons/print.png</iconset>
       </property>
       <property name="text">
        <string>Print</string>
       </property>
      </action>
      <action name="actionHelp">
       <property name="icon">
        <iconset resource="Icons/icons.qrc">
         <normaloff>:/Icons/help.png</normaloff>:/Icons/help.png</iconset>
       </property>
       <property name="text">
        <string>Help</string>
       </property>
      </action>
      <action name="actionSave">
       <property name="icon">
        <iconset resource="Icons/icons.qrc">
         <normaloff>:/Icons/filesave.png</normaloff>:/Icons/filesave.png</iconset>
       </property>
       <property name="text">
        <string>Save</string>
       </property>
      </action>
     </widget>
     <customwidgets>
      <customwidget>
       <class>QVTKOpenGLNativeWidget</class>
       <extends>QWidget</extends>
       <header>QVTKOpenGLNativeWidget.h</header>
      </customwidget>
     </customwidgets>
     <resources>
      <include location="Icons/icons.qrc"/>
     </resources>
     <connections/>
    </ui>

### CMakeLists.txt

    cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

    if(POLICY CMP0020)
      cmake_policy(SET CMP0020 NEW)
      cmake_policy(SET CMP0071 NEW)
    endif()

    PROJECT(ShareCameraQt)

    find_package(VTK COMPONENTS

      vtkCommonColor
      vtkCommonCore
      vtkFiltersCore
      vtkFiltersSources
      vtkInfovisCore
      vtkInteractionStyle
      vtkRenderingContextOpenGL2
      vtkRenderingCore
      vtkRenderingFreeType
      vtkRenderingGL2PSOpenGL2
      vtkRenderingOpenGL2
      vtkViewsQt
      QUIET
    )

    if (NOT VTK_FOUND)
      message("Skipping ShareCameraQt: ${VTK_NOT_FOUND_MESSAGE}")
      return ()
    endif()
    message (STATUS "VTK_VERSION: ${VTK_VERSION}")

    if(vtkGUISupportQt_LOADED OR TARGET VTK::GUISupportQt)
      if (VTK_VERSION VERSION_LESS "8.90.0")
        # Instruct CMake to run moc automatically when needed.
        set(CMAKE_AUTOMOC ON)
      else()
         # Instruct CMake to run moc automatically when needed.
        set(CMAKE_AUTOMOC ON)
        set(CMAKE_AUTOUIC ON)
      endif()
      # We have ui files, this will bring in the macro: qt5_wrap_ui
      find_package(Qt5Widgets REQUIRED QUIET)
    else()
      message(STATUS "GuiSupportQt not found.")
      return()
    endif()

    include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_CURRENT_BINARY_DIR})

    file(GLOB UI_FILES *.ui)
    file(GLOB QT_WRAP *.h)
    file(GLOB CXX_FILES *.cxx)

    qt5_wrap_ui(UISrcs ${UI_FILES})

    if (VTK_VERSION VERSION_LESS "8.90.0")
      # old system
      include(${VTK_USE_FILE})
      # CMAKE_AUTOMOC in ON so the MOC headers will be automatically wrapped.
      add_executable(ShareCameraQt MACOSX_BUNDLE
        ${CXX_FILES} ${UISrcs} ${QT_WRAP})
      qt5_use_modules(ShareCameraQt Core Gui)
      target_link_libraries(ShareCameraQt ${VTK_LIBRARIES})
    else()
      # CMAKE_AUTOMOC in ON so the MOC headers will be automatically wrapped.
      add_executable(ShareCameraQt MACOSX_BUNDLE
        ${CXX_FILES} ${UISrcs} ${QT_WRAP})
      qt5_use_modules(ShareCameraQt Core Gui)
      target_link_libraries(ShareCameraQt ${VTK_LIBRARIES})
      # vtk_module_autoinit is needed
      vtk_module_autoinit(
        TARGETS ShareCameraQt
        MODULES ${VTK_LIBRARIES}
      )
    endif()

### Download and Build ShareCameraQt

Click here to download ShareCameraQt and its CMakeLists.txt file. Once the tarball ShareCameraQt.tar has been downloaded and extracted,

     cd ShareCameraQt/build

This example requires Qt and VTK.

If VTK and Qt are installed:

     cmake ..

If VTK is not installed but compiled on your system, you will need to specify the path to your VTK build:

     cmake -DVTK_DIR:PATH=/home/me/vtk_build ..

If Qt is not found on your system, you will need to tell CMake where to find qmake:

    cmake -DQT_QMAKE_EXECUTABLE:FILEPATH=/usr/something/qmake  ..

Build the project:

    make

and run it:

    ./ShareCameraQt

WINDOWS USERS

Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time. You may also need to add a Qt related path.