Updated geojson package

Gopkg.lock

@@ -221,7 +221,8 @@
   version = "v1.1.0"
 
 [[projects]]
-  digest = "1:cdab3bce90a53a124ac3982719abde77d779e961d9c180e55c23fb74fc62563a"
+  branch = "master"
+  digest = "1:16a87d3d8d3808f3206c4992d1fb50440bb7d5508fbe5bfab7d899b516c7f3b8"
   name = "github.com/tidwall/geojson"
   packages = [
     ".",
@@ -229,8 +230,7 @@
     "geometry",
   ]
   pruneopts = ""
-  revision = "eaf6e0a55a79c1e879bbbcc879a3176c720d99cd"
-  version = "v1.1.3"
+  revision = "ff8d554639ee72ffa650eca1e02f03ab51193c7f"
 
 [[projects]]
   digest = "1:3ddca2bd5496c6922a2a9e636530e178a43c2a534ea6634211acdc7d10222794"

Gopkg.toml

@@ -34,8 +34,8 @@ required = [
   name = "github.com/tidwall/boxtree"
 
 [[constraint]]
+  branch = "master"
   name = "github.com/tidwall/geojson"
-  version = "1.1.3"
 
 [[constraint]]
   name = "github.com/Shopify/sarama"

vendor/github.com/tidwall/geojson/geo/geo.go

@@ -93,75 +93,60 @@ func BearingTo(latA, lonA, latB, lonB float64) float64 {
 func RectFromCenter(lat, lon, meters float64) (
 	minLat, minLon, maxLat, maxLon float64,
 ) {
-
-	// see http://janmatuschek.de/LatitudeLongitudeBoundingCoordinates#Latitude
+	// convert degrees to radians
 	lat *= radians
 	lon *= radians
 
-	r := meters / earthRadius // angular radius
+	// Calculate ANGULAR RADIUS
+	// see http://janmatuschek.de/LatitudeLongitudeBoundingCoordinates#UsingIndex
+	r := meters / earthRadius
 
+	// Calculate LATITUDE min and max
+	// see http://janmatuschek.de/LatitudeLongitudeBoundingCoordinates#Latitude
 	minLat = lat - r
 	maxLat = lat + r
 
+	// Calculate LONGITUDE min and max
+	// see http://janmatuschek.de/LatitudeLongitudeBoundingCoordinates#Longitude
 	latT := math.Asin(math.Sin(lat) / math.Cos(r))
 	lonΔ := math.Acos((math.Cos(r) - math.Sin(latT)*math.Sin(lat)) / (math.Cos(latT) * math.Cos(lat)))
 
 	minLon = lon - lonΔ
 	maxLon = lon + lonΔ
 
-	// Adjust for north poll
+	// ADJUST mins and maxes for edge-of-map cases
+	// see http://janmatuschek.de/LatitudeLongitudeBoundingCoordinates#PolesAnd180thMeridian
+
+	// adjust for NORTH POLE
 	if maxLat > math.Pi/2 {
 		minLon = -math.Pi
 		maxLat = math.Pi / 2
 		maxLon = math.Pi
 	}
 
-	// Adjust for south poll
+	// adjust for SOUTH POLE
 	if minLat < -math.Pi/2 {
 		minLat = -math.Pi / 2
 		minLon = -math.Pi
 		maxLon = math.Pi
 	}
 
-	// Adjust for wraparound. Remove this if the commented-out condition below this block is added.
+	/* adjust for WRAPAROUND
+
+	Creates a bounding box that wraps around the Earth like a belt, which
+	results in returning false positive candidates (candidates that are
+	farther away from the center than the distance of the search radius).
+
+	An alternative method, possibly to be implemented in the future, would be
+	to split the bounding box into two boxes. This would return fewer (or no)
+	false positives, but will require significant changes to the API's of
+	geoJSON and any of its dependents. */
 	if minLon < -math.Pi || maxLon > math.Pi {
 		minLon = -math.Pi
 		maxLon = math.Pi
 	}
 
-	/*
-	   	// Consider splitting area into two bboxes, using the below checks, and erasing above block for performance. See http://janmatuschek.de/LatitudeLongitudeBoundingCoordinates#PolesAnd180thMeridian
-	   	// Adjust for wraparound if minimum longitude is less than -180 degrees.
-	   	if lonMin < -math.Pi {
-	   // box 1:
-	   		latMin = latMin
-	   		latMax = latMax
-	   		lonMin += 2*math.Pi
-	   		lonMax = math.Pi
-	   // box 2:
-	   		latMin = latMin
-	   		latMax = latMax
-	   		lonMin = -math.Pi
-	   		lonMax = lonMax
-	   	}
-	   	// Adjust for wraparound if maximum longitude is greater than 180 degrees.
-	   	if lonMax > math.Pi {
-	   // box 1:
-	   		latMin = latMin
-	   		latMax = latMax
-	   		lonMin = lonMin
-	   		lonMax = -math.Pi
-	   // box 2:
-	   		latMin = latMin
-	   		latMax = latMax
-	   		lonMin = -math.Pi
-	   		lonMax -= 2*math.Pi
-	   	}
-	*/
-
-	minLon = math.Mod(minLon+3*math.Pi, 2*math.Pi) - math.Pi // normalise to -180..+180°
-	maxLon = math.Mod(maxLon+3*math.Pi, 2*math.Pi) - math.Pi
-
+	// convert radians to degrees
 	minLat *= degrees
 	minLon *= degrees
 	maxLat *= degrees

vendor/github.com/tidwall/geojson/geo/geo_test.go

@@ -41,6 +41,68 @@ func TestGeoCalc(t *testing.T) {
 	if value2 != lonB {
 		t.Fatalf("expected '%v', got '%v'", lonB, value2)
 	}
+	// RectFromCenter
+	// expected mins and maxes for wraparound and pole tests
+	expMinLat := -90.0
+	expMinLon := -180.0
+	expMaxLat := 90.0
+	expMaxLon := 180.0
+
+	dist1 := 1600000.0
+
+	wraparoundTests := []struct {
+		name                   string
+		lat, lon, searchRadius float64
+	}{
+		{name: "Wraparound E", lat: 0.0, lon: 179.0, searchRadius: dist1},  // at equator near 180th meridian East
+		{name: "Wraparound W", lat: 0.0, lon: -179.0, searchRadius: dist1}, // at equator near 180th meridian West
+	}
+
+	for _, tt := range wraparoundTests {
+		t.Run(tt.name, func(t *testing.T) {
+			_, minLon, _, maxLon := RectFromCenter(tt.lat, tt.lon, tt.searchRadius)
+			if !(minLon == expMinLon && maxLon == expMaxLon) {
+				t.Errorf("\nexpected minLon = '%v', maxLon = '%v'"+"\ngot minLon = '%v', maxLon = '%v'\n",
+					expMinLon, expMaxLon,
+					minLon, maxLon)
+			}
+		})
+	}
+
+	northPoleTests := []struct {
+		name                   string
+		lat, lon, searchRadius float64
+	}{
+		{name: "North Pole", lat: 89.0, lon: 90.0, searchRadius: dist1}, // near North Pole
+		{name: "North Pole: Tile38 iss422", lat: 13.0257553, lon: 77.6672509, searchRadius: 9000000.0},
+	}
+	for _, tt := range northPoleTests {
+		t.Run(tt.name, func(t *testing.T) {
+			_, minLon, maxLat, maxLon := RectFromCenter(tt.lat, tt.lon, tt.searchRadius)
+			if !(minLon == expMinLon && maxLat == expMaxLat && maxLon == expMaxLon) {
+				t.Errorf("\nexpected minLon = '%v', maxLat = '%v', maxLon = '%v'"+"\ngot minLon = '%v', maxLat = '%v', maxLon = '%v'",
+					expMinLon, expMaxLat, expMaxLon,
+					minLon, maxLat, maxLon)
+			}
+		})
+	}
+
+	southPoleTests := []struct {
+		name                   string
+		lat, lon, searchRadius float64
+	}{
+		{name: "South Pole", lat: -89.0, lon: 90.0, searchRadius: dist1}, // near South Pole
+	}
+	for _, tt := range southPoleTests {
+		t.Run(tt.name, func(t *testing.T) {
+			minLat, minLon, _, maxLon := RectFromCenter(tt.lat, tt.lon, tt.searchRadius)
+			if !(minLat == expMinLat && minLon == expMinLon && maxLon == expMaxLon) {
+				t.Errorf("\nexpected minLat = '%v', minLon = '%v', maxLon = '%v'"+"\ngot minLat = '%v', minLon = '%v', maxLon = '%v'",
+					expMinLat, expMinLon, expMaxLon,
+					minLat, minLon, maxLon)
+			}
+		})
+	}
 }
 
 func TestHaversine(t *testing.T) {