Function loadPFM

tutorials/common/image/pfm.cpp:25–67

! read PFM file from disk */

  /*! read PFM file from disk */
  Ref<Image> loadPFM(const FileName& fileName)
  {
    /* open file for reading */
    std::fstream file;
    file.exceptions (std::fstream::failbit | std::fstream::badbit);
    file.open (fileName.c_str(), std::fstream::in | std::fstream::binary);

    /* read file type */
    char cty[2]; file.read(cty,2);
    skipSpacesAndComments(file);
    std::string type(cty,2);

    /* read width, height, and maximum color value */
    int width; file >> width;
    skipSpacesAndComments(file);
    int height; file >> height;
    skipSpacesAndComments(file);
    float maxColor; file >> maxColor;
    if (maxColor > 0) THROW_RUNTIME_ERROR("Big endian PFM files not supported");
    float rcpMaxColor = -1.0f/float(maxColor);
    file.ignore(); // skip space or return

    /* create image and fill with data */
    Ref<Image> img = new Image4f(width,height,fileName);

    /* image in binary format 16 bit */
    if (type == "PF")
    {
      float rgb[3];
      for (ssize_t y=height-1; y>=0; y--) {
        for (ssize_t x=0; x<width; x++) {
          file.read((char*)rgb,sizeof(rgb));
          img->set(x,y,Color4(rgb[0]*rcpMaxColor,rgb[1]*rcpMaxColor,rgb[2]*rcpMaxColor,1.0f));
        }
      }
    }

    /* invalid magic value */
    else {
      THROW_RUNTIME_ERROR("Invalid magic value in PFM file");
    }
    return img;
  }

  /*! store PFM file to disk */
  void storePFM(const Ref<Image>& img, const FileName& fileName)