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ShareCameraQt

vtk-examples/Cxx/Qt/ShareCameraQt

Question

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Code

ShareCameraQt.cxx

#include "ShareCameraQt.h"
#include "ui_ShareCameraQt.h"

#include <vtkCamera.h>
#include <vtkCommand.h>
#include <vtkConeSource.h>
#include <vtkCubeSource.h>
#include <vtkGenericOpenGLRenderWindow.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkVersion.h>

#if VTK_VERSION_NUMBER >= 89000000000ULL
#define VTK890 1
#endif

// Constructor
ShareCameraQt::ShareCameraQt(QWidget* parent)
  : QMainWindow(parent), ui(new Ui::ShareCameraQt)
{
  this->ui->setupUi(this);

  vtkNew<vtkNamedColors> colors;

  vtkNew<vtkGenericOpenGLRenderWindow> renderWindowLeft;
  vtkNew<vtkGenericOpenGLRenderWindow> renderWindowRight;
#if VTK890
  this->ui->qvtkWidgetLeft->setRenderWindow(renderWindowLeft);
  this->ui->qvtkWidgetRight->setRenderWindow(renderWindowRight);
#else
  this->ui->qvtkWidgetLeft->SetRenderWindow(renderWindowLeft);
  this->ui->qvtkWidgetRight->SetRenderWindow(renderWindowRight);
#endif

  // Cone
  vtkNew<vtkConeSource> coneSource;
  coneSource->SetDirection(0.0, 1.0, 0.0);
  vtkNew<vtkPolyDataMapper> coneMapper;
  coneMapper->SetInputConnection(coneSource->GetOutputPort());
  vtkNew<vtkActor> coneActor;
  coneActor->SetMapper(coneMapper);
  coneActor->GetProperty()->SetColor(colors->GetColor4d("Tomato").GetData());

  // Cube
  vtkNew<vtkCubeSource> cubeSource;
  cubeSource->SetXLength(0.8);
  cubeSource->SetYLength(0.8);
  cubeSource->SetZLength(0.8);
  vtkNew<vtkPolyDataMapper> cubeMapper;
  cubeMapper->SetInputConnection(cubeSource->GetOutputPort());
  vtkNew<vtkActor> cubeActor;
  cubeActor->SetMapper(cubeMapper);
  cubeActor->GetProperty()->SetColor(
      colors->GetColor4d("MediumSeaGreen").GetData());

  // VTK Renderer.
  vtkNew<vtkRenderer> leftRenderer;
  leftRenderer->AddActor(coneActor);
  leftRenderer->SetBackground(colors->GetColor3d("LightSteelBlue").GetData());

  vtkNew<vtkRenderer> rightRenderer;

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

  // VTK/Qt wedded.
#if VTK890
  this->ui->qvtkWidgetLeft->renderWindow()->AddRenderer(leftRenderer);
  this->ui->qvtkWidgetRight->renderWindow()->AddRenderer(rightRenderer);
#else
  this->ui->qvtkWidgetLeft->GetRenderWindow()->AddRenderer(leftRenderer);
  this->ui->qvtkWidgetRight->GetRenderWindow()->AddRenderer(rightRenderer);
#endif

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

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

  // Position the cube using the left renderer active camera.
  leftRenderer->GetActiveCamera()->Azimuth(60);
  leftRenderer->ResetCamera();

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

#if VTK890
  this->ui->qvtkWidgetLeft->renderWindow()->AddObserver(
      vtkCommand::ModifiedEvent, this, &ShareCameraQt::ModifiedHandler);
#else
  this->ui->qvtkWidgetLeft->GetRenderWindow()->AddObserver(
      vtkCommand::ModifiedEvent, this, &ShareCameraQt::ModifiedHandler);
#endif
}

void ShareCameraQt::ModifiedHandler()
{
#if VTK890
  this->ui->qvtkWidgetRight->renderWindow()->Render();
#else
  this->ui->qvtkWidgetRight->GetRenderWindow()->Render();
#endif
}

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

ShareCameraQt.h

#ifndef ShareCameraQt_H
#define ShareCameraQt_H

#include <QMainWindow>

/*
 * See "The Single Inheritance Approach" in this link:
 * [Using a Designer UI File in Your C++
 * Application](https://doc.qt.io/qt-5/designer-using-a-ui-file.html)
 */
namespace Ui {
class ShareCameraQt;
}

class ShareCameraQt : public QMainWindow
{
  Q_OBJECT
public:
  // Constructor/Destructor
  explicit ShareCameraQt(QWidget* parent = nullptr);
  virtual ~ShareCameraQt() = default;

private:
  // Designer form
  Ui::ShareCameraQt* ui;

public slots:
  void slotExit();

protected:
  void ModifiedHandler();
};

#endif

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>

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();
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.12 FATAL_ERROR)

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

PROJECT(ShareCameraQt)

find_package(VTK COMPONENTS 
  CommonColor
  CommonCore
  FiltersSources
  InteractionStyle
  RenderingContextOpenGL2
  RenderingCore
  RenderingFreeType
  RenderingGL2PSOpenGL2
  RenderingOpenGL2
  GUISupportQt
  RenderingQt
)

if(NOT VTK_FOUND)
  message(FATAL_ERROR "ShareCameraQt: Unable to find the VTK build folder.")
endif()

if(NOT(TARGET VTK::GUISupportQt))
  message(FATAL_ERROR "ShareCameraQt: VTK not built with Qt support.")
endif()

if(NOT DEFINED VTK_QT_VERSION)
  set(VTK_QT_VERSION 5)
endif()

set(qt_components Core Gui Widgets)
if(${VTK_QT_VERSION} VERSION_GREATER_EQUAL 6)
  list(APPEND qt_components OpenGLWidgets)
endif()
list(SORT qt_components)
# We have ui files, so this will also bring in the macro:
#   qt5_wrap_ui or qt_wrap_ui from Widgets.
find_package(Qt${VTK_QT_VERSION} QUIET
  REQUIRED COMPONENTS ${qt_components}
)

foreach(_qt_comp IN LISTS qt_components)
  list(APPEND qt_modules "Qt${VTK_QT_VERSION}::${_qt_comp}")
endforeach()

message (STATUS "VTK_VERSION: ${VTK_VERSION}, Qt Version: ${Qt${VTK_QT_VERSION}Widgets_VERSION}")

# Instruct CMake to run moc and uic automatically when needed.
set(CMAKE_AUTOMOC ON)
set(CMAKE_AUTOUIC ON)

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)

# For VTK versions greater than or equal to 8.90.0:
#  CMAKE_AUTOUIC is ON so we handle uic automatically for Qt targets.
#  CMAKE_AUTOMOC is ON so we handle moc automatically for Qt targets.

# Prevent a "command line is too long" failure in Windows.
set(CMAKE_NINJA_FORCE_RESPONSE_FILE "ON" CACHE BOOL "Force Ninja to use response files.")
# CMAKE_AUTOMOC in ON so the MOC headers will be automatically wrapped.
add_executable(ShareCameraQt MACOSX_BUNDLE
  ${CXX_FILES} ${UISrcs} ${QT_WRAP}
)
if (Qt${VTK_QT_VERSION}Widgets_VERSION VERSION_LESS "5.11.0")
  qt5_use_modules(ShareCameraQt ${qt_components})
else()
  target_link_libraries(ShareCameraQt ${qt_modules})
endif()
target_link_libraries(ShareCameraQt ${VTK_LIBRARIES})
# vtk_module_autoinit is needed
vtk_module_autoinit(
  TARGETS ShareCameraQt
  MODULES ${VTK_LIBRARIES}
)

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=/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.