/** * Test geolib::expand(). * This test isn't yet working for edge cases, * expanding to the original precision or to the minimum precision. * Perhaps those expansions don't make much sense. * * @dataProvider geohashProvider * @param string $geohash */ public function testCircle($geohash) { $circle = new geohash_circle($geohash); $center = geohash::decode($geohash); $last_radius = 0; // test all precisions up to 0 do { $radius = $circle->max_radius() / EARTH_RADIUS; $circle->expand($geohash, $precision); // the center point should be in the set $this->assertTrue($circle->contains($center)); // the following tests only work for points away from the poles where radiuses expand usefully if ($radius > 0) { $this->assertGreaterThan($last_radius, $radius); // all points box size x 1 distance from the center should be in the set $this->assertTrue($circle->contains(new geopoint(min($center->latitude + $radius, 90), self::normalize_longitude($center->longitude + $radius)))); $this->assertTrue($circle->contains(new geopoint(min($center->latitude + $radius, 90), self::normalize_longitude($center->longitude - $radius)))); $this->assertTrue($circle->contains(new geopoint(max($center->latitude - $radius, -90), self::normalize_longitude($center->longitude + $radius)))); $this->assertTrue($circle->contains(new geopoint(max($center->latitude - $radius, -90), self::normalize_longitude($center->longitude - $radius)))); // at least one point box size x 2 distance from the center should be outside the set /* $this->assertFalse($circle->contains(new geopoint(min($center->latitude + $radius*2, 90), $center->longitude + $radius*2)) && $circle->contains(new geopoint(min($center->latitude + $radius*2, 90), $center->longitude - $radius*2)) && $circle->contains(new geopoint(max($center->latitude - $radius*2, -90), $center->longitude + $radius*2)) && $circle->contains(new geopoint(max($center->latitude - $radius*2, -90), $center->longitude - $radius*2))); */ $last_radius = $radius; } } while ($circle->expand()); }
/** * Increase the size the of the circle. * @param int $amount * @return boolean success|failure */ public function expand($amount = 1) { if ($this->precision == 1) { // currently unwilling to expand to cover the entire globe return false; } $this->precision = max($this->precision - $amount, 1); // shrink the geohash, grow the box $center = substr($this->center_geohash, 0, $this->precision); $box = geohash::decode_box($center); $dlat = $box->north - $box->south; $dlon = $box->east - $box->west; $set = new geohash_set(); $set->add($center); $quadrant = geohash::quadrant($this->center_geohash, $this->precision); if ($quadrant == geohash::northeast || $quadrant == geohash::northwest) { // north side $north = geohash::neighbor($center, geohash::north); if ($north) { $set->add_set(geohash::halve($north, geohash::south)); if ($quadrant == geohash::northeast) { $set->add_set(geohash::quarter(geohash::neighbor($north, geohash::east), geohash::southwest)); } else { // northwest $set->add_set(geohash::quarter(geohash::neighbor($north, geohash::west), geohash::southeast)); } $box->north += $dlat / 2; } } else { // south side $south = geohash::neighbor($center, geohash::south); if ($south) { $set->add_set(geohash::halve($south, geohash::north)); if ($quadrant == geohash::southeast) { $set->add_set(geohash::quarter(geohash::neighbor($south, geohash::east), geohash::northwest)); } else { // southwest $set->add_set(geohash::quarter(geohash::neighbor($south, geohash::west), geohash::northeast)); } $box->south -= $dlat / 2; } } if ($quadrant == geohash::northeast || $quadrant == geohash::southeast) { // east side $set->add_set(geohash::halve(geohash::neighbor($center, geohash::east), geohash::west)); $box->east += $dlon / 2; } else { // west side $set->add_set(geohash::halve(geohash::neighbor($center, geohash::west), geohash::east)); $box->west -= $dlon / 2; } $this->geohash_set = $set; $this->max_radius = min($this->center->distance_to_longitude($box->east), $this->center->distance_to_longitude($box->west)); if ($box->north < 90) { $this->max_radius = min($this->center->distance_to_latitude(min($box->north, 90)), $this->max_radius); } if ($box->south > -90) { $this->max_radius = min($this->center->distance_to_latitude(max($box->south, -90)), $this->max_radius); } return true; }