message: Fix fit-model-simple compile errors
diff: #include "eos/render/utils.hpp"
  #include "eos/render/texture_extraction.hpp"
  +#include "Eigen/Core"
  +
  #include "opencv2/core/core.hpp"
  #include "opencv2/highgui/highgui.hpp"
  @@ -41,9 +43,8 @@ namespace fs = boost::filesystem;
  using eos::core::Landmark;
  using eos::core::LandmarkCollection;
  using cv::Mat;
  -using cv::Vec2f;
  -using cv::Vec3f;
  -using cv::Vec4f;
  +using Eigen::Vector2f;
  +using Eigen::Vector4f;
  using std::cout;
  using std::endl;
  using std::vector;
  @@ -56,12 +57,12 @@ using std::string;
  * @param[in] filename Path to a .pts file.
  * @return An ordered vector with the 68 ibug landmarks.
  */
  -LandmarkCollection<cv::Vec2f> read_pts_landmarks(std::string filename)
  +LandmarkCollection<Eigen::Vector2f> read_pts_landmarks(std::string filename)
  {
  using std::getline;
  - using cv::Vec2f;
  + using core::Point2f;
  using std::string;
  - LandmarkCollection<Vec2f> landmarks;
  + LandmarkCollection<Point2f> landmarks;
  landmarks.reserve(68);
  std::ifstream file(filename);
  @@ -83,7 +84,7 @@ LandmarkCollection<cv::Vec2f> read_pts_landmarks(std::string filename)
  }
  std::stringstream lineStream(line);
  - Landmark<Vec2f> landmark;
  + Landmark<Point2f> landmark;
  landmark.name = std::to_string(ibugId);
  if (!(lineStream >> landmark.coordinates[0] >> landmark.coordinates[1])) {
  throw std::runtime_error(string("Landmark format error while parsing the line: " + line));
  @@ -145,7 +146,7 @@ int main(int argc, char *argv[])
  // Load the image, landmarks, LandmarkMapper and the Morphable Model:
  Mat image = cv::imread(imagefile.string());
  - LandmarkCollection<cv::Vec2f> landmarks;
  + LandmarkCollection<core::Point2f> landmarks;
  try {
  landmarks = read_pts_landmarks(landmarksfile.string());
  }
  @@ -170,9 +171,9 @@ int main(int argc, char *argv[])
  }
  // These will be the final 2D and 3D points used for the fitting:
  - vector<Vec4f> model_points; // the points in the 3D shape model
  + vector<Vector4f> model_points; // the points in the 3D shape model
  vector<int> vertex_indices; // their vertex indices
  - vector<Vec2f> image_points; // the corresponding 2D landmark points
  + vector<Vector2f> image_points; // the corresponding 2D landmark points
  // Sub-select all the landmarks which we have a mapping for (i.e. that are defined in the 3DMM):
  for (int i = 0; i < landmarks.size(); ++i) {
  @@ -182,7 +183,7 @@ int main(int argc, char *argv[])
  }
  int vertex_idx = std::stoi(converted_name.get());
  auto vertex = morphable_model.get_shape_model().get_mean_at_point(vertex_idx);
  - model_points.emplace_back(Vec4f(vertex.x(), vertex.y(), vertex.z(), 1.0f));
  + model_points.emplace_back(Vector4f(vertex.x(), vertex.y(), vertex.z(), 1.0f));
  vertex_indices.emplace_back(vertex_idx);
  image_points.emplace_back(landmarks[i].coordinates);
  }
  