gtsam/gtsam/slam/EssentialMatrixConstraint.h

146 lines
4.3 KiB
C++

/* ----------------------------------------------------------------------------
* GTSAM Copyright 2010-2014, Georgia Tech Research Corporation,
* Atlanta, Georgia 30332-0415
* All Rights Reserved
* Authors: Frank Dellaert, et al. (see THANKS for the full author list)
* See LICENSE for the license information
* -------------------------------------------------------------------------- */
/**
* @file EssentialMatrixConstraint.h
* @author Frank Dellaert
* @author Pablo Alcantarilla
* @date Jan 5, 2014
**/
#pragma once
#include <gtsam/nonlinear/NonlinearFactor.h>
#include <gtsam/linear/GaussianFactor.h>
#include <gtsam/geometry/EssentialMatrix.h>
#include <gtsam/base/Testable.h>
#include <ostream>
namespace gtsam {
/**
* Binary factor between two Pose3 variables induced by an EssentialMatrix measurement
* @addtogroup SLAM
*/
class EssentialMatrixConstraint: public NoiseModelFactor2<Pose3, Pose3> {
private:
typedef EssentialMatrixConstraint This;
typedef NoiseModelFactor2<Pose3, Pose3> Base;
EssentialMatrix measuredE_; /** The measurement is an essential matrix */
public:
// shorthand for a smart pointer to a factor
typedef boost::shared_ptr<EssentialMatrixConstraint> shared_ptr;
/** default constructor - only use for serialization */
EssentialMatrixConstraint() {
}
/**
* Constructor
* @param key1 key for first pose
* @param key2 key for second pose
* @param measuredE measured EssentialMatrix
* @param model noise model, 5D !
*/
EssentialMatrixConstraint(Key key1, Key key2,
const EssentialMatrix& measuredE, const SharedNoiseModel& model) :
Base(model, key1, key2), measuredE_(measuredE) {
}
virtual ~EssentialMatrixConstraint() {
}
/// @return a deep copy of this factor
virtual gtsam::NonlinearFactor::shared_ptr clone() const {
return boost::static_pointer_cast<gtsam::NonlinearFactor>(
gtsam::NonlinearFactor::shared_ptr(new This(*this)));
}
/** implement functions needed for Testable */
/** print */
virtual void print(const std::string& s, const KeyFormatter& keyFormatter =
DefaultKeyFormatter) const {
std::cout << s << "EssentialMatrixConstraint(" << keyFormatter(this->key1())
<< "," << keyFormatter(this->key2()) << ")\n";
measuredE_.print(" measured: ");
this->noiseModel_->print(" noise model: ");
}
/** equals */
virtual bool equals(const NonlinearFactor& expected,
double tol = 1e-9) const {
const This *e = dynamic_cast<const This*>(&expected);
return e != NULL && Base::equals(*e, tol)
&& this->measuredE_.equals(e->measuredE_, tol);
}
/** implement functions needed to derive from Factor */
/** vector of errors */
Vector evaluateError(const Pose3& p1, const Pose3& p2,
boost::optional<Matrix&> Hp1 = boost::none, //
boost::optional<Matrix&> Hp2 = boost::none) const {
// compute relative Pose3 between p1 and p2
Pose3 _1P2_ = p1.between(p2, Hp1, Hp2);
// convert to EssentialMatrix
Matrix D_hx_1P2;
EssentialMatrix hx = EssentialMatrix::FromPose3(_1P2_,
(Hp1 || Hp2) ? boost::optional<Matrix&>(D_hx_1P2) : boost::none);
// Calculate derivatives if needed
if (Hp1) {
// Hp1 will already contain the 6*6 derivative D_1P2_p1
const Matrix& D_1P2_p1 = *Hp1;
// The 5*6 derivative is obtained by chaining with 5*6 D_hx_1P2:
*Hp1 = D_hx_1P2 * D_1P2_p1;
}
if (Hp2) {
// Hp2 will already contain the 6*6 derivative D_1P2_p1
const Matrix& D_1P2_p2 = *Hp2;
// The 5*6 derivative is obtained by chaining with 5*6 D_hx_1P2:
*Hp2 = D_hx_1P2 * D_1P2_p2;
}
// manifold equivalent of h(x)-z -> log(z,h(x))
return measuredE_.localCoordinates(hx); // 5D error
}
/** return the measured */
const EssentialMatrix& measured() const {
return measuredE_;
}
/** number of variables attached to this factor */
std::size_t size() const {
return 2;
}
private:
/** Serialization function */
friend class boost::serialization::access;
template<class ARCHIVE>
void serialize(ARCHIVE & ar, const unsigned int version) {
ar
& boost::serialization::make_nvp("NoiseModelFactor2",
boost::serialization::base_object<Base>(*this));
ar & BOOST_SERIALIZATION_NVP(measuredE_);
}
};
// \class EssentialMatrixConstraint
}/// namespace gtsam