osrm-backend/include/extractor/guidance/intersection_normalizer.hpp
Moritz Kobitzsch 2ddd98ee6d simplify passing annotation data through OSRM pipeline using the node-based datastore
- separates node-based graph creation and compression from edge-based graph creation
 - moves usage of edge-based node data-container to pre-processing as well, unifying access to node-based data
 - single struct instead of separate vectors for annotation data in engine (single place of modification)
2017-10-09 18:44:43 +02:00

126 lines
5.5 KiB
C++

#ifndef OSRM_EXTRACTOR_GUIDANCE_INTERSECTION_NORMALIZER_HPP_
#define OSRM_EXTRACTOR_GUIDANCE_INTERSECTION_NORMALIZER_HPP_
#include "util/attributes.hpp"
#include "util/name_table.hpp"
#include "util/typedefs.hpp"
#include "extractor/guidance/coordinate_extractor.hpp"
#include "extractor/guidance/intersection.hpp"
#include "extractor/guidance/intersection_generator.hpp"
#include "extractor/guidance/intersection_normalization_operation.hpp"
#include "extractor/guidance/mergable_road_detector.hpp"
#include "extractor/query_node.hpp"
#include "extractor/suffix_table.hpp"
#include <utility>
#include <vector>
namespace osrm
{
namespace extractor
{
namespace guidance
{
/*
* An intersection is a central part in computing guidance decisions. However the model in OSM and
* the view we want to use in guidance are not necessarily the same thing. We have to account for
* some models that are chosen explicitly in OSM and that don't actually describe how a human would
* experience an intersection.
*
* For example, if a small pedestrian island is located at a traffic light right in the middle of a
* road, OSM tends to model the road as two separate ways. A human would consider these two ways a
* single road, though. In this normalizer, we try to account for these subtle differences between
* OSM data and human perception to improve our decision base for guidance later on.
*/
class IntersectionNormalizer
{
public:
struct NormalizationResult
{
IntersectionShape normalized_shape;
std::vector<IntersectionNormalizationOperation> performed_merges;
};
IntersectionNormalizer(const util::NodeBasedDynamicGraph &node_based_graph,
const EdgeBasedNodeDataContainer &node_data_container,
const std::vector<util::Coordinate> &node_coordinates,
const util::NameTable &name_table,
const SuffixTable &street_name_suffix_table,
const IntersectionGenerator &intersection_generator);
// The function takes an intersection an converts it to a `perceived` intersection which closer
// represents how a human might experience the intersection
OSRM_ATTR_WARN_UNUSED
NormalizationResult operator()(const NodeID node_at_intersection,
IntersectionShape intersection) const;
private:
const util::NodeBasedDynamicGraph &node_based_graph;
const IntersectionGenerator &intersection_generator;
const MergableRoadDetector mergable_road_detector;
/* check if two indices in an intersection can be seen as a single road in the perceived
* intersection representation. See below for an example. Utility function for
* MergeSegregatedRoads. It also checks for neighboring merges.
* This is due possible segments where multiple roads could end up being merged into one.
* We only support merging two roads, not three or more, though.
* c c
* / /
* a - b -> a - b - (c,d) but not a - b d -> a,b,(cde)
* \ \
* d e
*/
bool CanMerge(const NodeID intersection_node,
const IntersectionShape &intersection,
std::size_t first_index,
std::size_t second_index) const;
// Perform an Actual Merge
IntersectionNormalizationOperation
DetermineMergeDirection(const IntersectionShapeData &lhs,
const IntersectionShapeData &rhs) const;
IntersectionShapeData MergeRoads(const IntersectionShapeData &destination,
const IntersectionShapeData &source) const;
IntersectionShapeData MergeRoads(const IntersectionNormalizationOperation direction,
const IntersectionShapeData &lhs,
const IntersectionShapeData &rhs,
const double opposite_bearing) const;
// Merge segregated roads to omit invalid turns in favor of treating segregated roads as
// one.
// This function combines roads the following way:
//
// * *
// * is converted to *
// v ^ +
// v ^ +
//
// The treatment results in a straight turn angle of 180º rather than a turn angle of approx
// 160
OSRM_ATTR_WARN_UNUSED
NormalizationResult MergeSegregatedRoads(const NodeID intersection_node,
IntersectionShape intersection) const;
// The counterpiece to mergeSegregatedRoads. While we can adjust roads that split up at the
// intersection itself, it can also happen that intersections are connected to joining roads.
//
// * *
// * is converted to *
// v a --- a ---
// v ^ +
// v ^ +
// b
//
// for the local view of b at a.
OSRM_ATTR_WARN_UNUSED
IntersectionShape AdjustBearingsForMergeAtDestination(const NodeID node_at_intersection,
IntersectionShape intersection) const;
};
} // namespace guidance
} // namespace extractor
} // namespace osrm
#endif /* OSRM_EXTRACTOR_GUIDANCE_INTERSECTION_NORMALIZER_HPP_ */