cartographer/cartographer/mapping/submaps.h

127 lines
4.4 KiB
C++

/*
* Copyright 2016 The Cartographer Authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef CARTOGRAPHER_MAPPING_SUBMAPS_H_
#define CARTOGRAPHER_MAPPING_SUBMAPS_H_
#include <memory>
#include <vector>
#include "Eigen/Geometry"
#include "cartographer/common/math.h"
#include "cartographer/common/port.h"
#include "cartographer/mapping/id.h"
#include "cartographer/mapping/probability_values.h"
#include "cartographer/mapping/proto/submap_visualization.pb.h"
#include "cartographer/mapping/trajectory_node.h"
#include "cartographer/mapping_2d/probability_grid.h"
#include "glog/logging.h"
namespace cartographer {
namespace mapping {
// Converts the given probability to log odds.
inline float Logit(float probability) {
return std::log(probability / (1.f - probability));
}
const float kMaxLogOdds = Logit(kMaxProbability);
const float kMinLogOdds = Logit(kMinProbability);
// Converts a probability to a log odds integer. 0 means unknown, [kMinLogOdds,
// kMaxLogOdds] is mapped to [1, 255].
inline uint8 ProbabilityToLogOddsInteger(const float probability) {
const int value = common::RoundToInt((Logit(probability) - kMinLogOdds) *
254.f / (kMaxLogOdds - kMinLogOdds)) +
1;
CHECK_LE(1, value);
CHECK_GE(255, value);
return value;
}
// An individual submap, which has a 'local_pose' in the local SLAM frame, keeps
// track of how many range data were inserted into it, and sets the
// 'finished_probability_grid' to be used for loop closing once the map no
// longer changes.
struct Submap {
Submap(const transform::Rigid3d& local_pose) : local_pose(local_pose) {}
// Local SLAM pose of this submap.
const transform::Rigid3d local_pose;
// Number of RangeData inserted.
int num_range_data = 0;
// The 'finished_probability_grid' when this submap is finished and will not
// change anymore. Otherwise, this is nullptr and the next call to
// InsertRangeData() will change the submap.
const mapping_2d::ProbabilityGrid* finished_probability_grid = nullptr;
};
// Submaps is a sequence of maps to which scans are matched and into which scans
// are inserted.
//
// Except during initialization when only a single submap exists, there are
// always two submaps into which scans are inserted: an old submap that is used
// for matching, and a new one, which will be used for matching next, that is
// being initialized.
//
// Once a certain number of scans have been inserted, the new submap is
// considered initialized: the old submap is no longer changed, the "new" submap
// is now the "old" submap and is used for scan-to-map matching. Moreover,
// a "new" submap gets inserted.
class Submaps {
public:
static constexpr uint8 kUnknownLogOdds = 0;
Submaps();
virtual ~Submaps();
Submaps(const Submaps&) = delete;
Submaps& operator=(const Submaps&) = delete;
// Returns the index of the newest initialized Submap which can be
// used for scan-to-map matching.
int matching_index() const;
// Returns the indices of the Submap into which point clouds will
// be inserted.
std::vector<int> insertion_indices() const;
// Returns the Submap with the given 'index'. The same 'index' will always
// return the same pointer, so that Submaps can be identified by it.
virtual const Submap* Get(int index) const = 0;
// Returns the number of Submaps.
virtual int size() const = 0;
// Fills data about the Submap with 'index' into the 'response'.
virtual void SubmapToProto(int index,
const transform::Rigid3d& global_submap_pose,
proto::SubmapQuery::Response* response) const = 0;
protected:
static void AddProbabilityGridToResponse(
const transform::Rigid3d& local_submap_pose,
const mapping_2d::ProbabilityGrid& probability_grid,
proto::SubmapQuery::Response* response);
};
} // namespace mapping
} // namespace cartographer
#endif // CARTOGRAPHER_MAPPING_SUBMAPS_H_