VTKでPointCloud表示

#pragma once

// https://stackoverflow.com/questions/7591204/how-to-display-point-cloud-in-vtk-in-different-colors
#include <vtkRenderer.h>
#include <vtkSmartPointer.h>

#include <vtkPolyData.h> //vtkPolyData用
#include <vtkPolyDataMapper.h>
#include <vtkPointData.h> // 頂点データ用

#include <vtkUnsignedCharArray.h> //色データ用
#include <vtkProperty.h>

//#include <vtkPoints.h>
//#include <vtkPolygon.h>

class VtkPointCloud {

public:

  vtkSmartPointer<vtkPolyData> _polydata;
  vtkSmartPointer<vtkPolyDataMapper> _mapper;
  vtkSmartPointer<vtkActor> _actor;
  vtkSmartPointer < vtkPoints > _points;
  vtkSmartPointer < vtkCellArray > _cells;

  vtkSmartPointer < vtkUnsignedCharArray > _colors;

  VtkPointCloud(double zMin = -10.0, double zMax = 10.0, int maxNumPoints = 1e6) {

    _polydata = vtkSmartPointer<vtkPolyData>::New();
    clearPoints();
    _mapper = vtkSmartPointer<vtkPolyDataMapper>::New();
    _mapper->SetInputData(_polydata);
    _mapper->SetColorModeToDefault();
    //_mapper->SetScalarRange(zMin, zMax);
    _mapper->SetScalarVisibility(1);
    _actor = vtkSmartPointer<vtkActor>::New();
    _actor->SetMapper(_mapper);
  }

  void addPoint(double point[3], unsigned char color[3]) {

    vtkIdType pointId = _points->InsertNextPoint(point);
    _cells->InsertNextCell(1);
    _cells->InsertCellPoint(pointId);
    _colors->InsertNextTuple3(color[0], color[1], color[2]);

  }

  void clearPoints() {
    _points = vtkSmartPointer < vtkPoints >::New();
    _cells = vtkSmartPointer < vtkCellArray>::New();

    ////////////////////////////////////
    _colors = vtkSmartPointer<vtkUnsignedCharArray>::New();
    _colors->SetNumberOfComponents(3);
    _colors->SetName("Colors");
    _polydata->GetPointData()->SetScalars(_colors);
    _polydata->GetPointData()->SetActiveScalars("Colors");
    ////////////////////////////////////

    _polydata->SetPoints(_points);
    _polydata->SetVerts(_cells);

  }


};

#pragma once

#include "VTK_PointCloud.hpp"


// VTK_MODULE_INITに必要
#include <vtkAutoInit.h>

#include <vtkRenderer.h>
#include <vtkRenderWindow.h>
#include <vtkWin32RenderWindowInteractor.h> //win32api対応
#include <vtkInteractorStyleImage.h>

////////////////////////////////////////////////////////

#pragma comment(lib,"vtkCommonCore-9.1.lib")
#pragma comment(lib,"vtkRenderingCore-9.1.lib")
#pragma comment(lib,"vtkInteractionStyle-9.1.lib")
#pragma comment(lib,"vtkCommonDataModel-9.1.lib ") // ポリゴン用

#pragma comment(lib,"vtkRenderingOpenGL2-9.1.lib")


//必須
VTK_MODULE_INIT(vtkRenderingOpenGL2);
VTK_MODULE_INIT(vtkInteractionStyle);


int main(int argc, char** argv)
{

  // 点群生成
  auto ptc = std::make_unique< VtkPointCloud>();
  for (size_t i = 0; i < 100000; i++) {
    double x = (double)rand() / (double)RAND_MAX;
    double y = (double)rand() / (double)RAND_MAX;
    double z = (double)rand() / (double)RAND_MAX;
    ptc->addPoint(
      std::array<double, 3>{ x, y, z }.data(),
      std::array<unsigned char, 3>{ (unsigned char)(x * 255), (unsigned char)(y * 255), (unsigned char)(z * 255)}.data()
    );
  }

  // 頂点サイズを指定する場合
  // #include <vtkProperty.h>
  ptc->_actor->GetProperty()->SetPointSize(3);

  //////////////////////////////////////////////////////////////////
  //////////////////////////////////////////////////////////////////
  //////////////////////////////////////////////////////////////////
  //////////////////////////////////////////////////////////////////

  vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New();
  renderer->AddActor(ptc->_actor);
  renderer->ResetCamera();

  //////////////////////////////////////
  auto interactor = vtkSmartPointer<vtkRenderWindowInteractor>::New();

  vtkSmartPointer<vtkInteractorStyleTrackballCamera> style =
    vtkSmartPointer<vtkInteractorStyleTrackballCamera>::New();
  interactor->SetInteractorStyle(style);

  //////////////////////////////////////
  auto renderWindow = vtkSmartPointer<vtkRenderWindow>::New();
  renderWindow->AddRenderer(renderer);
  renderWindow->SetInteractor(interactor);
  renderWindow->Render();

  interactor->Start(); //イベントループへ入る

  return 0;
}