GeoSearch::GeoSearch(Collection* collection,
TwoDAccessMethod* accessMethod,
const Point& startPt,
int numWanted,
MatchExpression* filter,
double maxDistance,
GeoDistType type)
: GeoHopper(collection, accessMethod, numWanted, startPt, filter, maxDistance, type),
_start(accessMethod->getParams().geoHashConverter->hash(startPt.x, startPt.y)),
_numWanted(numWanted),
_type(type),
_params(accessMethod->getParams()) {
_nscanned = 0;
_found = 0;
if(_maxDistance < 0){
_scanDistance = numeric_limits<double>::max();
} else if (type == GEO_PLANE) {
_scanDistance = maxDistance + _params.geoHashConverter->getError();
} else if (type == GEO_SPHERE) {
checkEarthBounds(startPt);
// TODO: consider splitting into x and y scan distances
_scanDistance = computeXScanDistance(startPt.y,
rad2deg(_maxDistance) + _params.geoHashConverter->getError());
}
verify(_scanDistance > 0);
}
bool GeoCircleBrowse::exactDocCheck(const Point& p, double& d){
switch (_type) {
case GEO_PLANE: {
if(distanceWithin(_startPt, p, _maxDistance)) return true;
break;
}
case GEO_SPHERE:
checkEarthBounds(p);
if(spheredist_deg(_startPt, p) <= _maxDistance) return true;
break;
default: verify(false);
}
return false;
}
bool GeoHopper::exactDocCheck(const Point& p, double& d){
bool within = false;
// Get the appropriate distance for the type
switch (_type) {
case GEO_PLANE:
d = distance(_near, p);
within = distanceWithin(_near, p, _maxDistance);
break;
case GEO_SPHERE:
checkEarthBounds(p);
d = spheredist_deg(_near, p);
within = (d <= _maxDistance);
break;
default: verify(false);
}
return within;
}
GeoAccumulator:: KeyResult GeoHopper::approxKeyCheck(const Point& p, double& d) {
// Always check approximate distance, since it lets us avoid doing
// checks of the rest of the object if it succeeds
switch (_type) {
case GEO_PLANE:
d = distance(_near, p);
break;
case GEO_SPHERE:
checkEarthBounds(p);
d = spheredist_deg(_near, p);
break;
default: verify(false);
}
verify(d >= 0);
// If we need more points
double borderDist = (_points.size() < _max ? _maxDistance : farthest());
if (d >= borderDist - 2 * _distError && d <= borderDist + 2 * _distError) return BORDER;
else return d < borderDist ? GOOD : BAD;
}
GeoAccumulator::KeyResult GeoCircleBrowse::approxKeyCheck(const Point& p, double& d) {
// Inexact hash distance checks.
double error = 0;
switch (_type) {
case GEO_PLANE:
d = distance(_startPt, p);
error = _converter->getError();
break;
case GEO_SPHERE: {
checkEarthBounds(p);
d = spheredist_deg(_startPt, p);
error = _converter->getErrorSphere();
break;
}
default: verify(false);
}
// If our distance is in the error bounds...
if(d >= _maxDistance - error && d <= _maxDistance + error) return BORDER;
return d > _maxDistance ? BAD : GOOD;
}