void MaximalSublineStringMatcher::_validateElement(const ConstOsmMapPtr& map, ElementId eid) const
{
ConstElementPtr e = map->getElement(eid);
if (e->getElementType() == ElementType::Relation)
{
ConstRelationPtr r = dynamic_pointer_cast<const Relation>(e);
if (OsmSchema::getInstance().isMultiLineString(*r) == false)
{
throw NeedsReviewException("Internal Error: When matching sublines expected a multilinestring "
"relation not a " + r->getType() + ". A non-multilinestring should never be found here. "
"Please report this to [email protected]");
}
const vector<RelationData::Entry>& entries = r->getMembers();
for (size_t i = 0; i < entries.size(); i++)
{
if (entries[i].getElementId().getType() != ElementType::Way)
{
throw NeedsReviewException("MultiLineString relations can only contain ways when matching "
"sublines.");
}
}
}
if (e->getElementType() == ElementType::Way)
{
ConstWayPtr w = dynamic_pointer_cast<const Way>(e);
if (w->getNodeCount() <= 1)
{
throw NeedsReviewException("Internal Error: Attempting to match against a zero length way.");
}
}
}
void MaximalSublineStringMatcher::_validateElement(const ConstOsmMapPtr& map, ElementId eid) const
{
ConstElementPtr e = map->getElement(eid);
if (e->getElementType() == ElementType::Relation)
{
ConstRelationPtr r = dynamic_pointer_cast<const Relation>(e);
if (OsmSchema::getInstance().isMultiLineString(*r) == false)
{
throw NeedsReviewException("When matching sublines expected a multilinestring relation not"
" a " + r->getType());
}
const vector<RelationData::Entry>& entries = r->getMembers();
for (size_t i = 0; i < entries.size(); i++)
{
if (entries[i].getElementId().getType() != ElementType::Way)
{
throw NeedsReviewException("MultiLineString relations can only contain ways when matching "
"sublines.");
}
}
}
}
WaySublineMatchString MaximalSublineStringMatcher::findMatch(const ConstOsmMapPtr& map,
const ConstElementPtr& e1, const ConstElementPtr& e2, Meters maxRelevantDistance) const
{
assert(_maxAngle >= 0);
if (maxRelevantDistance == -1)
{
maxRelevantDistance = e1->getCircularError() + e2->getCircularError();
}
// make sure the inputs are legit. If either element isn't legit then throw a NeedsReviewException
_validateElement(map, e1->getElementId());
_validateElement(map, e2->getElementId());
// extract the ways from the elements. In most cases it will return a vector of 1, but
// multilinestrings may contain multiple ways
vector<ConstWayPtr> ways1 = ExtractWaysVisitor::extractWays(map, e1);
vector<ConstWayPtr> ways2 = ExtractWaysVisitor::extractWays(map, e2);
if ((ways1.size() > 4 && ways2.size() > 4) || (ways1.size() + ways2.size() > 7))
{
throw NeedsReviewException("Elements contain too many ways and the computational complexity "
"is unreasonable.");
}
// Try with all combinations of forward and reversed ways. This is very expensive for
// multilinestrings with lots of ways in them. Though those shouldn't be common.
vector<bool> reversed1(ways1.size(), false), reversed2(ways2.size(), false);
ScoredMatch scoredResult = _findBestMatch(map, maxRelevantDistance, ways1, ways2, reversed1,
reversed2);
// convert the best match into a WaySublineStringMatch and return.
try
{
WaySublineMatchString result = scoredResult.matches;
// this likely shouldn't be necessary. See #4593
result.removeEmptyMatches();
return result;
}
catch(OverlappingMatchesException &e)
{
throw NeedsReviewException("Internal Error: Multiple overlapping way matches were found within "
"one set of ways. Please report this to [email protected].");
}
}
