# RestoreSceneFromFile

### Description

Given a filename, vtkActor and vtkCamera, reads necessary variables to recreate the scene from a file.

Note

The snippet currently just restores the vtkCamera variables.

To use the snippet, click the Copy to clipboard at the upper right of the code blocks.

### Declaration Section

    #include <vtkActor.h>
    #include <vtkCamera.h>
    namespace
    {
    void RestoreSceneFromFile(std::string fileName,
                              vtkActor *actor,
                              vtkCamera *camera);
    }

### Implementation Section

    namespace
    {
    #include <fstream>
    void RestoreSceneFromFile(std::string fileName,
                              vtkActor *actor,
                              vtkCamera *camera)
    {
      std::ifstream saveFile(fileName);
      std::string line;
      double vector[3];
      double scalar;

      vtksys::RegularExpression reCP("^Camera:Position");
      vtksys::RegularExpression reCFP("^Camera:FocalPoint");
      vtksys::RegularExpression reCVU("^Camera:ViewUp");
      vtksys::RegularExpression reCVA("^Camera:ViewAngle");
      vtksys::RegularExpression reCCR("^Camera:ClippingRange");
      vtksys::RegularExpression floatNumber(
          "[^0-9\\.\\-]*([0-9e\\.\\-]*[^,])[^0-9\\.\\-]*([0-9e\\.\\-]*[^,])[^0-9\\.\\-]*([0-9e\\.\\-]*[^,])");
      vtksys::RegularExpression floatScalar("[^0-9\\.\\-]*([0-9\\.\\-e]*[^,])");

      while (std::getline(saveFile, line) && ! saveFile.eof())
      {
        if (reCFP.find(line))
        {
          std::string rest(line, reCFP.end());
          if (floatNumber.find(rest))
          {
            camera->SetFocalPoint(
              atof(floatNumber.match(1).c_str()),
              atof(floatNumber.match(2).c_str()),
              atof(floatNumber.match(3).c_str()));
          }
        }
        else if (reCP.find(line))
        {
          std::string rest(line, reCP.end());
          if (floatNumber.find(rest))
          {
            camera->SetPosition(
              atof(floatNumber.match(1).c_str()),
              atof(floatNumber.match(2).c_str()),
              atof(floatNumber.match(3).c_str()));
          }
        }
        else if (reCVU.find(line))
        {
          std::string rest(line, reCVU.end());
          if (floatNumber.find(rest))
          {
            camera->SetViewUp(
              atof(floatNumber.match(1).c_str()),
              atof(floatNumber.match(2).c_str()),
              atof(floatNumber.match(3).c_str()));
          }
        }
        else if (reCVA.find(line))
        {
          std::string rest(line, reCVA.end());
          if (floatScalar.find(rest))
          {
            camera->SetViewAngle(
              atof(floatScalar.match(1).c_str()));
          }
        }
        else if (reCCR.find(line))
        {
          std::string rest(line, reCCR.end());
          if (floatNumber.find(rest))
          {
            camera->SetClippingRange(
              atof(floatNumber.match(1).c_str()),
              atof(floatNumber.match(2).c_str()));
          }
        }
        else
        {
          std::cout << "Unrecognized line: " << line << std::endl;
        }
      }
      saveFile.close();
    }
    }