// Ceres Solver - A fast non-linear least squares minimizer
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// Author: vitus@google.com (Michael Vitus)
//
// Defines the types used in the 2D pose graph SLAM formulation. Each vertex of
// the graph has a unique integer ID with a position and orientation. There are
// delta transformation constraints between two vertices.

#ifndef CERES_EXAMPLES_POSE_GRAPH_2D_TYPES_H_
#define CERES_EXAMPLES_POSE_GRAPH_2D_TYPES_H_

#include "Eigen/Core"

namespace ceres {
namespace examples {

// The state for each vertex in the pose graph.
struct Pose2d {
  double x;
  double y;
  double yaw_radians;
};

// The constraint between two vertices in the pose graph. The constraint is the
// transformation from vertex id_begin to vertex id_end.
struct Constraint2d {
  int id_begin;
  int id_end;

  double x;
  double y;
  double yaw_radians;

  // The inverse of the covariance matrix for the measurement. The order of the
  // entries are x, y, and yaw.
  Eigen::Matrix3d information;
};

}  // namespace examples
}  // namespace ceres

#endif  // CERES_EXAMPLES_POSE_GRAPH_2D_TYPES_H_