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ResetCameraOrientation

vtk-examples/Cxx/Utilities/ResetCameraOrientation


Description

This example demonstrates how to reset the camera orientation.

In this case, the original orientation is stored, a new orientation calculated, and, finally the original orientation is restored. The original, new and restored orientations of the cone are displayed in one second intervals. After this you can interact with the scene.

To set the camera position, you can use:

  • SetPosition, SetFocalPoint, SetViewUp, SetDistance, SetClippingRange
  • Roll, Elevation, Azimuth
  • SetRoll, Pitch, Yaw

If you haven't used SetDistance or SetClippingRange remember to ren->ResetCamera(); or ren.ResetCamera().

Other languages

See (Python)

Question

If you have a question about this example, please use the VTK Discourse Forum

Code

ResetCameraOrientation.cxx

#include <vtkActor.h>
#include <vtkCamera.h>
#include <vtkConeSource.h>
#include <vtkInteractorStyleTrackballCamera.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>

#include <chrono>
#include <iomanip>
#include <iostream>
#include <sstream>
#include <string>
#include <thread>
#include <vector>

namespace {

//! The positional information relating to the camera.
struct Orientation
{
  void ToVector(const double* from, std::vector<double>& to)
  {
    for (size_t i = 0; i < to.size(); ++i)
    {
      to[i] = from[i];
    }
  };

  std::vector<double> position{0.0, 0.0, 0.0};
  std::vector<double> focalPoint{0.0, 0.0, 0.0};
  std::vector<double> viewUp{0.0, 0.0, 0.0};
  double distance = 0;
  std::vector<double> clipplingRange{0.0, 0.0};
  std::vector<double> orientation{0.0, 0.0, 0.0};
};

//! Produce a comma-separated string of numbers from a vector.
/*
 *
 * @param v - the vector of doubles.
 * @param precision - number of decimal places.
 * @param width - the width.
 * @return A comma-separated string.
 */
std::string CommaSeparatedList(std::vector<double> const& v,
                               const int precision = 6, const int width = 10);

//! Get the camera orientation.
/*
 * @param ren - the renderer.
 * @return The orientation parameters.
 */
Orientation GetOrientation(vtkRenderer* ren);

//! Set the camera orientation.
/*
 *
 * @param ren - the renderer.
 * @param p - The orientation parameters.
 * @return
 */
void SetOrientation(vtkRenderer* ren, Orientation const& p);

} // namespace

int main(int, char*[])
{
  vtkNew<vtkNamedColors> colors;

  vtkNew<vtkConeSource> cone;
  cone->SetHeight(3.0);
  cone->SetRadius(1.0);
  cone->SetResolution(10);

  vtkNew<vtkPolyDataMapper> coneMapper;
  coneMapper->SetInputConnection(cone->GetOutputPort());

  vtkNew<vtkActor> coneActor;
  coneActor->SetMapper(coneMapper);
  coneActor->GetProperty()->SetColor(colors->GetColor3d("Bisque").GetData());

  vtkNew<vtkRenderer> ren;
  ren->AddActor(coneActor);
  ren->SetBackground(colors->GetColor3d("MidnightBlue").GetData());

  vtkNew<vtkRenderWindow> renWin;
  renWin->AddRenderer(ren);
  renWin->SetSize(600, 600);
  renWin->SetWindowName("ResetCameraOrientation");

  vtkNew<vtkRenderWindowInteractor> iren;
  iren->SetRenderWindow(renWin);

  vtkNew<vtkInteractorStyleTrackballCamera> style;
  iren->SetInteractorStyle(style);

  vtkCamera* camera = ren->GetActiveCamera();
  camera->SetRoll(15);
  camera->Elevation(-15);
  camera->Azimuth(30);
  ren->ResetCamera();

  renWin->Render();
  Orientation originalOrient = GetOrientation(ren);
  std::cout << std::setw(23) << "Original orientation:"
            << CommaSeparatedList(originalOrient.orientation) << std::endl;
  std::this_thread::sleep_for(std::chrono::seconds(1));

  camera->SetPosition(-3.568189, 5.220048, 2.352639);
  camera->SetFocalPoint(-0.399044, -0.282865, 0.131438);
  camera->SetViewUp(0.623411, 0.573532, -0.531431);
  camera->SetDistance(6.727500);
  camera->SetClippingRange(3.001430, 11.434082);
  // No need to use ren->ResetCamera() as we have all the parameters.
  renWin->Render();
  Orientation newOrient = GetOrientation(ren);
  std::cout << std::setw(23)
            << "New orientation:" << CommaSeparatedList(newOrient.orientation)
            << std::endl;
  std::this_thread::sleep_for(std::chrono::seconds(1));

  std::cout << "Reloading the original orientation." << std::endl;
  SetOrientation(ren, originalOrient);
  renWin->Render();
  Orientation check = GetOrientation(ren);
  std::cout << std::setw(23)
            << "Final orientation:" << CommaSeparatedList(check.orientation)
            << std::endl;
  std::this_thread::sleep_for(std::chrono::seconds(1));

  iren->Initialize();
  iren->Start();

  return EXIT_SUCCESS;
}

namespace {
std::string CommaSeparatedList(std::vector<double> const& v,
                               const int precision, const int width)
{
  std::ostringstream os;
  for (auto p = v.begin(); p < v.end() - 1; ++p)
  {
    os << std::fixed << std::setw(width) << std::setprecision(precision) << *p
       << ", ";
  }
  os << std::fixed << std::setw(width) << std::setprecision(precision)
     << v.back();
  return os.str();
}

Orientation GetOrientation(vtkRenderer* ren)
{
  Orientation p;

  vtkCamera* camera = ren->GetActiveCamera();
  p.ToVector(camera->GetPosition(), p.position);
  p.ToVector(camera->GetFocalPoint(), p.focalPoint);
  p.ToVector(camera->GetViewUp(), p.viewUp);
  p.distance = camera->GetDistance();
  p.ToVector(camera->GetClippingRange(), p.clipplingRange);
  p.ToVector(camera->GetOrientation(), p.orientation);

  return p;
}

void SetOrientation(vtkRenderer* ren, Orientation const& p)
{
  vtkCamera* camera = ren->GetActiveCamera();
  camera->SetPosition(p.position.data());
  camera->SetFocalPoint(p.focalPoint.data());
  camera->SetViewUp(p.viewUp.data());
  camera->SetDistance(p.distance);
  camera->SetClippingRange(p.clipplingRange.data());
}

} // namespace

CMakeLists.txt

cmake_minimum_required(VERSION 3.12 FATAL_ERROR)

project(ResetCameraOrientation)

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

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

# 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.")
add_executable(ResetCameraOrientation MACOSX_BUNDLE ResetCameraOrientation.cxx )
  target_link_libraries(ResetCameraOrientation PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
  TARGETS ResetCameraOrientation
  MODULES ${VTK_LIBRARIES}
)

Download and Build ResetCameraOrientation

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

cd ResetCameraOrientation/build

If VTK is 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 ..

Build the project:

make

and run it:

./ResetCameraOrientation

WINDOWS USERS

Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.