Better polygon detection logic

Refactored shared detection logic.
Fixed linestring, multilinestring, and multipoint bugs.
Added more geojson unit tests.

geojson/detect.go

@@ -0,0 +1,294 @@
+package geojson
+
+import (
+	"github.com/tidwall/tile38/geojson/poly"
+)
+
+// withinObjectShared returns true if g is within o
+func withinObjectShared(g, o Object) bool {
+	bbp := o.bboxPtr()
+	if bbp != nil {
+		if !g.WithinBBox(*bbp) {
+			return false
+		}
+		if o.IsBBoxDefined() {
+			return true
+		}
+	}
+	switch o := o.(type) {
+	default:
+		return false
+	case SimplePoint:
+		return g.WithinBBox(o.CalculatedBBox())
+	case Point:
+		return g.WithinBBox(o.CalculatedBBox())
+	case MultiPoint:
+		for i := range o.Coordinates {
+			if g.Within(o.getPoint(i)) {
+				return true
+			}
+		}
+		return false
+	case LineString:
+		if len(o.Coordinates) == 0 {
+			return false
+		}
+		switch g := g.(type) {
+		default:
+			return false
+		case SimplePoint:
+			return poly.Point(Position{X: g.X, Y: g.Y, Z: 0}).IntersectsLineString(polyPositions(o.Coordinates))
+		case Point:
+			return poly.Point(g.Coordinates).IntersectsLineString(polyPositions(o.Coordinates))
+		case MultiPoint:
+			if len(o.Coordinates) == 0 {
+				return false
+			}
+			for _, p := range o.Coordinates {
+				if !poly.Point(p).IntersectsLineString(polyPositions(o.Coordinates)) {
+					return false
+				}
+			}
+			return true
+		}
+	case MultiLineString:
+		for i := range o.Coordinates {
+			if g.Within(o.getLineString(i)) {
+				return true
+			}
+		}
+		return false
+	case MultiPolygon:
+		for i := range o.Coordinates {
+			if g.Within(o.getPolygon(i)) {
+				return true
+			}
+		}
+		return false
+	case Feature:
+		return g.Within(o.Geometry)
+	case FeatureCollection:
+		for _, o := range o.Features {
+			if g.Within(o) {
+				return true
+			}
+		}
+		return false
+	case GeometryCollection:
+		for _, o := range o.Geometries {
+			if g.Within(o) {
+				return true
+			}
+		}
+		return false
+	case Polygon:
+		if len(o.Coordinates) == 0 {
+			return false
+		}
+		exterior, holes := polyExteriorHoles(o.Coordinates)
+		switch g := g.(type) {
+		default:
+			return false
+		case SimplePoint:
+			return poly.Point(Position{X: g.X, Y: g.Y, Z: 0}).Inside(exterior, holes)
+		case Point:
+			return poly.Point(g.Coordinates).Inside(exterior, holes)
+		case MultiPoint:
+			if len(g.Coordinates) == 0 {
+				return false
+			}
+			for i := range g.Coordinates {
+				if !g.getPoint(i).Within(o) {
+					return false
+				}
+			}
+			return true
+		case LineString:
+			return polyPositions(g.Coordinates).Inside(exterior, holes)
+		case MultiLineString:
+			if len(g.Coordinates) == 0 {
+				return false
+			}
+			for i := range g.Coordinates {
+				if !g.getLineString(i).Within(o) {
+					return false
+				}
+			}
+			return true
+		case Polygon:
+			if len(g.Coordinates) == 0 {
+				return false
+			}
+			return polyPositions(g.Coordinates[0]).Inside(exterior, holes)
+		case MultiPolygon:
+			if len(g.Coordinates) == 0 {
+				return false
+			}
+			for i := range g.Coordinates {
+				if !g.getPolygon(i).Within(o) {
+					return false
+				}
+			}
+			return true
+		case GeometryCollection:
+			if len(g.Geometries) == 0 {
+				return false
+			}
+			for _, g := range g.Geometries {
+				if !g.Within(o) {
+					return false
+				}
+			}
+			return true
+		case Feature:
+			return g.Geometry.Within(o)
+		case FeatureCollection:
+			if len(g.Features) == 0 {
+				return false
+			}
+			for _, g := range g.Features {
+				if !g.Within(o) {
+					return false
+				}
+			}
+			return true
+		}
+	}
+}
+
+// intersectsObjectShared detects if g intersects with o
+func intersectsObjectShared(g, o Object) bool {
+	bbp := o.bboxPtr()
+	if bbp != nil {
+		if !g.IntersectsBBox(*bbp) {
+			return false
+		}
+		if o.IsBBoxDefined() {
+			return true
+		}
+	}
+	switch o := o.(type) {
+	default:
+		return false
+	case SimplePoint:
+		return g.IntersectsBBox(o.CalculatedBBox())
+	case Point:
+		return g.IntersectsBBox(o.CalculatedBBox())
+	case MultiPoint:
+		for i := range o.Coordinates {
+			if o.getPoint(i).Intersects(g) {
+				return true
+			}
+		}
+		return false
+	case LineString:
+		if g, ok := g.(LineString); ok {
+			a := polyPositions(g.Coordinates)
+			b := polyPositions(o.Coordinates)
+			return a.LineStringIntersectsLineString(b)
+		}
+		return o.Intersects(g)
+	case MultiLineString:
+		for i := range o.Coordinates {
+			if g.Intersects(o.getLineString(i)) {
+				return true
+			}
+		}
+		return false
+	case MultiPolygon:
+		for i := range o.Coordinates {
+			if g.Intersects(o.getPolygon(i)) {
+				return true
+			}
+		}
+		return false
+	case Feature:
+		return g.Intersects(o.Geometry)
+	case FeatureCollection:
+		for _, f := range o.Features {
+			if g.Intersects(f) {
+				return true
+			}
+		}
+		return false
+	case GeometryCollection:
+		for _, f := range o.Geometries {
+			if g.Intersects(f) {
+				return true
+			}
+		}
+		return false
+	case Polygon:
+		if len(o.Coordinates) == 0 {
+			return false
+		}
+		exterior, holes := polyExteriorHoles(o.Coordinates)
+		switch g := g.(type) {
+		default:
+			return false
+		case SimplePoint:
+			return poly.Point(Position{X: g.X, Y: g.Y, Z: 0}).Intersects(exterior, holes)
+		case Point:
+			return poly.Point(g.Coordinates).Intersects(exterior, holes)
+		case MultiPoint:
+			for i := range g.Coordinates {
+				if g.getPoint(i).Intersects(o) {
+					return true
+				}
+			}
+			return false
+		case LineString:
+			return polyPositions(g.Coordinates).LineStringIntersects(exterior, holes)
+		case MultiLineString:
+			for i := range g.Coordinates {
+				if g.getLineString(i).Intersects(o) {
+					return true
+				}
+			}
+			return false
+		case Polygon:
+			if len(g.Coordinates) == 0 {
+				return false
+			}
+			return polyPositions(g.Coordinates[0]).Intersects(exterior, holes)
+		case MultiPolygon:
+			for i := range g.Coordinates {
+				if g.getPolygon(i).Intersects(o) {
+					return true
+				}
+			}
+			return false
+		case GeometryCollection:
+			for _, g := range g.Geometries {
+				if g.Intersects(o) {
+					return true
+				}
+			}
+			return false
+		case Feature:
+			return g.Geometry.Intersects(o)
+		case FeatureCollection:
+			for _, g := range g.Features {
+				if g.Intersects(o) {
+					return true
+				}
+			}
+			return false
+		}
+	}
+}
+
+// The object's calculated bounding box must intersect the radius of the circle to pass.
+func nearbyObjectShared(g Object, x, y float64, meters float64) bool {
+	if !g.hasPositions() {
+		return false
+	}
+	center := Position{X: x, Y: y, Z: 0}
+	bbox := g.CalculatedBBox()
+	if bbox.Min.X == bbox.Max.X && bbox.Min.Y == bbox.Max.Y {
+		// just a point, return is point is inside of the circle
+		return center.DistanceTo(bbox.Min) <= meters
+	}
+	circlePoly := CirclePolygon(x, y, meters, 12)
+	return g.Intersects(circlePoly)
+}

geojson/detect_test.go

@@ -0,0 +1,362 @@
+package geojson
+
+import (
+	"testing"
+
+	"github.com/tidwall/gjson"
+)
+
+// https://gist.github.com/tidwall/5524c468fa4212b89e9c3532a5b1f355
+var detectJSON = `{"type":"FeatureCollection","features":[
+	{"type":"Feature","properties":{"id":"point1"},"geometry":{"type":"Point","coordinates":[-73.98549556732178,40.72198994979771]}},
+	{"type":"Feature","properties":{"id":"polygon1"},"geometry":{"type":"Polygon","coordinates":[[[-74.0035629272461,40.71994085251552],[-73.98914337158203,40.71994085251552],[-73.98914337158203,40.72755146730012],[-74.0035629272461,40.72755146730012],[-74.0035629272461,40.71994085251552]]]}},
+	{"type":"Feature","properties":{"id":"linestring1"},"geometry":{"type":"LineString","coordinates":[[-73.98382186889648,40.73652697126574],[-73.98821868896482,40.73652697126574],[-73.97420883178711,40.72943772441242]]}},
+	{"type":"Feature","properties":{"id":"linestring2"},"geometry":{"type":"LineString","coordinates":[[-73.98146152496338,40.72716120053256],[-73.99098873138428,40.724754504892424]]}},
+	{"type":"Feature","properties":{"id":"linestring3"},"geometry":{"type":"LineString","coordinates":[[-73.98386478424072,40.72696606629052],[-73.98090362548828,40.72501469240076],[-73.97837162017821,40.72621804639551]]}},
+	{"type":"Feature","properties":{"id":"polygon2","fill":"#0433ff"},"geometry":{"type":"Polygon","coordinates":[[[-73.98661136627197,40.72540497175607],[-73.99064540863037,40.71938791069558],[-73.98807048797607,40.71779411151556],[-73.97571086883545,40.72338850378556],[-73.98017406463623,40.72960033028089],[-73.98661136627197,40.72540497175607]]]}},
+	{"type":"Feature","properties":{"id":"polygon3"},"geometry":{"type":"Polygon","coordinates":[[[-73.98352146148682,40.72550254123727],[-73.98579597473145,40.72088409560772],[-73.97914409637451,40.72251034541217],[-73.98017406463623,40.72599038649773],[-73.98352146148682,40.72550254123727]],[[-73.98300647735596,40.72439674540761],[-73.98111820220947,40.72446179272971],[-73.98141860961913,40.7221525738643],[-73.98300647735596,40.72439674540761]]]}},
+	{"type":"Feature","properties":{"id":"multipoint1","marker-color":"#941751"},"geometry":{"type":"MultiPoint","coordinates":[[-73.98957252502441,40.72049378974239],[-73.9897871017456,40.720233584560724],[-73.9897871017456,40.721664700472566],[-73.99085998535155,40.720916620993194],[-73.9912462234497,40.720331161623065]]}},
+	{"type":"Feature","properties":{"id":"multilinestring1","stroke":"#941751"},"geometry":{"type":"MultiLineString","coordinates":[[[-73.98442268371582,40.72459188718318],[-73.98463726043701,40.72384384060296],[-73.98382186889648,40.72355112443509]],[[-73.9850664138794,40.72358364851732],[-73.98476600646973,40.72485207532725],[-73.9854097366333,40.72491712220435]]]}},
+	{"type":"Feature","properties":{"id":"multipolygon1","fill":"#941751"},"geometry":{"type":"MultiPolygon","coordinates":[[[[-73.98021697998047,40.72429917430525],[-73.97892951965332,40.7250472157678],[-73.98000240325926,40.72524235563617],[-73.98021697998047,40.72429917430525]]],[[[-73.97901535034178,40.72452683998823],[-73.9788007736206,40.72345355209305],[-73.97764205932617,40.72410403167144],[-73.97901535034178,40.72452683998823]]]]}},
+	{"type":"Feature","properties":{"id":"point2"},"geometry":{"type":"Point","coordinates":[-73.98326396942139,40.723681220668624]}},
+	{"type":"Feature","properties":{"id":"point3"},"geometry":{"type":"Point","coordinates":[-73.98196396942139,40.723681220668624]}},
+	{"type":"Feature","properties":{"id":"point4"},"geometry":{"type":"Point","coordinates":[-73.9785396942139,40.7238220668624]}}
+]}`
+
+func getByID(id string) Object {
+	var r gjson.Result
+	gjson.Get(detectJSON, "features").ForEach(func(_, v gjson.Result) bool {
+		if v.Get("properties.id").String() == id {
+			r = v.Get("geometry")
+			return false
+		}
+		return true
+	})
+	if !r.Exists() {
+		panic("not found '" + id + "'")
+	}
+	o, err := ObjectJSON(r.String())
+	if err != nil {
+		panic(err)
+	}
+	if p, ok := o.(SimplePoint); ok {
+		o = Point{Coordinates: Position{X: p.X, Y: p.Y}}
+	}
+	return o
+}
+
+func toSimplePoint(p Object) Object {
+	return SimplePoint{X: p.(Point).Coordinates.X, Y: p.(Point).Coordinates.Y}
+}
+
+// Basic geometry detections
+// Point -> Point
+// Point -> MultiPoint
+// Point -> LineString
+// Point -> MultiLineString
+// Point -> Polygon
+// Point -> MultiPolygon
+// MultiPoint -> Point
+// MultiPoint -> MultiPoint
+// MultiPoint -> LineString
+// MultiPoint -> MultiLineString
+// MultiPoint -> Polygon
+// MultiPoint -> MultiPolygon
+// LineString -> Point
+// LineString -> MultiPoint
+// LineString -> LineString
+// LineString -> MultiLineString
+// LineString -> Polygon
+// LineString -> MultiPolygon
+// MultiLineString -> Point
+// MultiLineString -> MultiPoint
+// MultiLineString -> LineString
+// MultiLineString -> MultiLineString
+// MultiLineString -> Polygon
+// MultiLineString -> MultiPolygon
+// Polygon -> Point
+// Polygon -> MultiPoint
+// Polygon -> LineString
+// Polygon -> MultiLineString
+// Polygon -> Polygon
+// Polygon -> MultiPolygon
+// MultiPolygon -> Point
+// MultiPolygon -> MultiPoint
+// MultiPolygon -> LineString
+// MultiPolygon -> MultiLineString
+// MultiPolygon -> Polygon
+// MultiPolygon -> MultiPolygon
+
+func TestDetectSimplePointSimplePoint(t *testing.T) {
+	p1 := toSimplePoint(getByID("point1"))
+	p2 := toSimplePoint(getByID("point2"))
+	if p1.Intersects(p2) {
+		t.Fatal("expected false")
+	}
+	if !p1.Intersects(p1) {
+		t.Fatal("expected true")
+	}
+	if p1.Within(p2) {
+		t.Fatal("expected false")
+	}
+	if !p1.Within(p1) {
+		t.Fatal("expected true")
+	}
+}
+func TestDetectPointPoint(t *testing.T) {
+	p1 := getByID("point1")
+	p2 := getByID("point2")
+	if p1.Intersects(p2) {
+		t.Fatal("expected false")
+	}
+	if !p1.Intersects(p1) {
+		t.Fatal("expected true")
+	}
+	if p1.Within(p2) {
+		t.Fatal("expected false")
+	}
+	if !p1.Within(p1) {
+		t.Fatal("expected true")
+	}
+}
+func TestDetectPointMultPoint(t *testing.T) {
+	p1 := getByID("point1")
+	mp1 := getByID("multipoint1")
+	if p1.Intersects(mp1) {
+		t.Fatal("expected false")
+	}
+	if p1.Within(mp1) {
+		t.Fatal("expected false")
+	}
+	pp := Point{Coordinates: mp1.(MultiPoint).Coordinates[0]}
+	if !pp.Intersects(mp1) {
+		t.Fatal("expected true")
+	}
+	if !pp.Within(mp1) {
+		t.Fatal("expected true")
+	}
+}
+func TestDetectPointLineString(t *testing.T) {
+	p1 := getByID("point1")
+	ls1 := getByID("linestring1")
+	if p1.Intersects(ls1) {
+		t.Fatal("expected false")
+	}
+	if p1.Within(ls1) {
+		t.Fatal("expected false")
+	}
+	pp := Point{Coordinates: ls1.(LineString).Coordinates[0]}
+	if !pp.Intersects(ls1) {
+		t.Fatal("expected true")
+	}
+	if !pp.Within(ls1) {
+		t.Fatal("expected true")
+	}
+}
+func TestDetectPointMultiLineString(t *testing.T) {
+	p1 := getByID("point1")
+	mls1 := getByID("multilinestring1")
+	if p1.Intersects(mls1) {
+		t.Fatal("expected false")
+	}
+	if p1.Within(mls1) {
+		t.Fatal("expected false")
+	}
+	pp := Point{Coordinates: mls1.(MultiLineString).Coordinates[0][1]}
+	if !pp.Intersects(mls1) {
+		t.Fatal("expected true")
+	}
+	if !pp.Within(mls1) {
+		t.Fatal("expected true")
+	}
+}
+func TestDetectPointPolygon(t *testing.T) {
+	p1 := getByID("point1")
+	pl3 := getByID("polygon3")
+	if p1.Intersects(pl3) {
+		t.Fatal("expected false")
+	}
+	if p1.Within(pl3) {
+		t.Fatal("expected false")
+	}
+	p2 := getByID("point2")
+	if !p2.Intersects(pl3) {
+		t.Fatal("expected true")
+	}
+	if !p2.Within(pl3) {
+		t.Fatal("expected true")
+	}
+	p3 := getByID("point3")
+	if p3.Intersects(pl3) {
+		t.Fatal("expected false")
+	}
+	if p3.Within(pl3) {
+		t.Fatal("expected false")
+	}
+}
+
+func TestDetectPointMultiPolygon(t *testing.T) {
+	p3 := getByID("point3")
+	p4 := getByID("point4")
+	mp1 := getByID("multipolygon1")
+	if p3.Intersects(mp1) {
+		t.Fatal("expected false")
+	}
+	if p3.Within(mp1) {
+		t.Fatal("expected false")
+	}
+	if !p4.Intersects(mp1) {
+		t.Fatal("expected true")
+	}
+	if !p4.Within(mp1) {
+		t.Fatal("expected true")
+	}
+}
+
+func TestDetectMultiPointPoint(t *testing.T) {
+	p1 := getByID("point1")
+	mp1 := getByID("multipoint1")
+	if mp1.Intersects(p1) {
+		t.Fatal("expected false")
+	}
+	if mp1.Within(p1) {
+		t.Fatal("expected false")
+	}
+	pp := Point{Coordinates: mp1.(MultiPoint).Coordinates[0]}
+	if !mp1.Intersects(pp) {
+		t.Fatal("expected true")
+	}
+	if mp1.Within(pp) {
+		t.Fatal("expected false")
+	}
+}
+
+func TestDetectMultiPointPolygon(t *testing.T) {
+	mp1 := getByID("multipoint1")
+	pl1 := getByID("polygon1")
+	pl2 := getByID("polygon2")
+	pl3 := getByID("polygon3")
+	if !mp1.Intersects(pl1) {
+		t.Fatal("expected true")
+	}
+	if !mp1.Within(pl1) {
+		t.Fatal("expected true")
+	}
+	if !mp1.Intersects(pl2) {
+		t.Fatal("expected true")
+	}
+	if mp1.Within(pl2) {
+		t.Fatal("expected false")
+	}
+	if mp1.Intersects(pl3) {
+		t.Fatal("expected false")
+	}
+	if mp1.Within(pl3) {
+		t.Fatal("expected false")
+	}
+}
+
+func TestDetectLineStringLineString(t *testing.T) {
+	ls1 := getByID("linestring1")
+	ls2 := getByID("linestring2")
+	ls3 := getByID("linestring3")
+	if ls1.Intersects(ls2) {
+		t.Fatal("expected false")
+	}
+	if ls2.Intersects(ls1) {
+		t.Fatal("expected false")
+	}
+	if !ls2.Intersects(ls3) {
+		t.Fatal("expected true")
+	}
+	if !ls2.Intersects(ls3) {
+		t.Fatal("expected true")
+	}
+}
+func TestDetectLineStringPolygon(t *testing.T) {
+	ls1 := getByID("linestring1")
+	ls2 := getByID("linestring2")
+	ls3 := getByID("linestring3")
+	pl1 := getByID("polygon1")
+	pl2 := getByID("polygon2")
+	pl3 := getByID("polygon3")
+
+	if ls1.Intersects(pl1) {
+		t.Fatal("expected false")
+	}
+	if pl1.Intersects(ls1) {
+		t.Fatal("expected false")
+	}
+	if ls1.Intersects(pl3) {
+		t.Fatal("expected false")
+	}
+	if pl3.Intersects(ls1) {
+		t.Fatal("expected false")
+	}
+	if !ls2.Intersects(pl1) {
+		t.Fatal("expected true")
+	}
+	if !pl2.Intersects(ls2) {
+		t.Fatal("expected true")
+	}
+	if ls2.Within(pl1) {
+		t.Fatal("expected false")
+	}
+	if ls2.Intersects(pl3) {
+		t.Fatal("expected false")
+	}
+	if pl3.Intersects(ls2) {
+		t.Fatal("expected false")
+	}
+	if !ls3.Intersects(pl2) {
+		t.Fatal("expected true")
+	}
+	if !pl2.Intersects(ls3) {
+		t.Fatal("expected true")
+	}
+	if !ls3.Within(pl2) {
+		t.Fatal("expected true")
+	}
+	if ls2.Intersects(pl3) {
+		t.Fatal("expected false")
+	}
+	if pl3.Intersects(ls2) {
+		t.Fatal("expected false")
+	}
+	if ls2.Intersects(pl3) {
+		t.Fatal("expected false")
+	}
+	if pl3.Intersects(ls2) {
+		t.Fatal("expected false")
+	}
+	if !ls3.Intersects(pl3) {
+		t.Fatal("expected true")
+	}
+	if !pl3.Intersects(ls3) {
+		t.Fatal("expected true")
+	}
+}
+func TestDetectMultiLineStringPolygon(t *testing.T) {
+	mls1 := getByID("multilinestring1")
+	pl1 := getByID("polygon1")
+	pl2 := getByID("polygon2")
+	pl3 := getByID("polygon3")
+	if mls1.Intersects(pl1) {
+		t.Fatal("expected false")
+	}
+	if mls1.Within(pl1) {
+		t.Fatal("expected false")
+	}
+	if !mls1.Intersects(pl2) {
+		t.Fatal("expected true")
+	}
+	if !mls1.Within(pl2) {
+		t.Fatal("expected true")
+	}
+	if !mls1.Intersects(pl3) {
+		t.Fatal("expected true")
+	}
+	if mls1.Within(pl3) {
+		t.Fatal("expected false")
+	}
+}

geojson/feature.go

@@ -192,20 +192,12 @@ func (g Feature) IntersectsBBox(bbox BBox) bool {
 
 // Within detects if the object is fully contained inside another object.
 func (g Feature) Within(o Object) bool {
-	return withinObjectShared(g, o,
-		func(v Polygon) bool {
-			return g.Geometry.Within(o)
-		},
-	)
+	return withinObjectShared(g, o)
 }
 
 // Intersects detects if the object intersects another object.
 func (g Feature) Intersects(o Object) bool {
-	return intersectsObjectShared(g, o,
-		func(v Polygon) bool {
-			return g.Geometry.Intersects(o)
-		},
-	)
+	return intersectsObjectShared(g, o)
 }
 
 // Nearby detects if the object is nearby a position.

geojson/featurecollection.go

@@ -178,36 +178,12 @@ func (g FeatureCollection) IntersectsBBox(bbox BBox) bool {
 
 // Within detects if the object is fully contained inside another object.
 func (g FeatureCollection) Within(o Object) bool {
-	return withinObjectShared(g, o,
-		func(v Polygon) bool {
-			if len(g.Features) == 0 {
-				return false
-			}
-			for _, f := range g.Features {
-				if !f.Within(o) {
-					return false
-				}
-			}
-			return true
-		},
-	)
+	return withinObjectShared(g, o)
 }
 
 // Intersects detects if the object intersects another object.
 func (g FeatureCollection) Intersects(o Object) bool {
-	return intersectsObjectShared(g, o,
-		func(v Polygon) bool {
-			if len(g.Features) == 0 {
-				return false
-			}
-			for _, f := range g.Features {
-				if f.Intersects(o) {
-					return true
-				}
-			}
-			return false
-		},
-	)
+	return intersectsObjectShared(g, o)
 }
 
 // Nearby detects if the object is nearby a position.

geojson/geometrycollection.go

@@ -177,36 +177,12 @@ func (g GeometryCollection) IntersectsBBox(bbox BBox) bool {
 
 // Within detects if the object is fully contained inside another object.
 func (g GeometryCollection) Within(o Object) bool {
-	return withinObjectShared(g, o,
-		func(v Polygon) bool {
-			if len(g.Geometries) == 0 {
-				return false
-			}
-			for _, g := range g.Geometries {
-				if !g.Within(o) {
-					return false
-				}
-			}
-			return true
-		},
-	)
+	return withinObjectShared(g, o)
 }
 
 // Intersects detects if the object intersects another object.
 func (g GeometryCollection) Intersects(o Object) bool {
-	return intersectsObjectShared(g, o,
-		func(v Polygon) bool {
-			if len(g.Geometries) == 0 {
-				return false
-			}
-			for _, g := range g.Geometries {
-				if g.Intersects(o) {
-					return true
-				}
-			}
-			return false
-		},
-	)
+	return intersectsObjectShared(g, o)
 }
 
 // Nearby detects if the object is nearby a position.

geojson/linestring.go

@@ -98,20 +98,12 @@ func (g LineString) IntersectsBBox(bbox BBox) bool {
 
 // Within detects if the object is fully contained inside another object.
 func (g LineString) Within(o Object) bool {
-	return withinObjectShared(g, o,
-		func(v Polygon) bool {
-			return polyPositions(g.Coordinates).Inside(polyExteriorHoles(v.Coordinates))
-		},
-	)
+	return withinObjectShared(g, o)
 }
 
 // Intersects detects if the object intersects another object.
 func (g LineString) Intersects(o Object) bool {
-	return intersectsObjectShared(g, o,
-		func(v Polygon) bool {
-			return polyPositions(g.Coordinates).LineStringIntersects(polyExteriorHoles(v.Coordinates))
-		},
-	)
+	return intersectsObjectShared(g, o)
 }
 
 // Nearby detects if the object is nearby a position.

geojson/multilinestring.go

@@ -2,7 +2,6 @@ package geojson
 
 import (
 	"github.com/tidwall/tile38/geojson/geohash"
-	"github.com/tidwall/tile38/geojson/poly"
 )
 
 // MultiLineString is a geojson object with the type "MultiLineString"
@@ -10,32 +9,50 @@ type MultiLineString struct {
 	Coordinates [][]Position
 	BBox        *BBox
 	bboxDefined bool
+	linestrings []LineString
 }
 
 func fillMultiLineString(coordinates [][]Position, bbox *BBox, err error) (MultiLineString, error) {
+	linestrings := make([]LineString, len(coordinates))
 	if err == nil {
-		for _, coordinates := range coordinates {
-			if len(coordinates) < 2 {
-				err = errLineStringInvalidCoordinates
+		for i, ps := range coordinates {
+			linestrings[i], err = fillLineString(ps, nil, nil)
+			if err != nil {
 				break
 			}
 		}
 	}
 	bboxDefined := bbox != nil
 	if !bboxDefined {
-		cbbox := level3CalculatedBBox(coordinates, nil, false)
+		cbbox := mlCalculatedBBox(linestrings, nil)
 		bbox = &cbbox
 	}
 	return MultiLineString{
 		Coordinates: coordinates,
 		BBox:        bbox,
 		bboxDefined: bboxDefined,
+		linestrings: linestrings,
 	}, err
 }
 
+func mlCalculatedBBox(linestrings []LineString, bbox *BBox) BBox {
+	if bbox != nil {
+		return *bbox
+	}
+	var cbbox BBox
+	for i, g := range linestrings {
+		if i == 0 {
+			cbbox = g.CalculatedBBox()
+		} else {
+			cbbox = cbbox.union(g.CalculatedBBox())
+		}
+	}
+	return cbbox
+}
+
 // CalculatedBBox is exterior bbox containing the object.
 func (g MultiLineString) CalculatedBBox() BBox {
-	return level3CalculatedBBox(g.Coordinates, g.BBox, false)
+	return mlCalculatedBBox(g.linestrings, g.BBox)
 }
 
 // CalculatedPoint is a point representation of the object.
@@ -93,6 +110,13 @@ func (g MultiLineString) hasPositions() bool {
 	return false
 }
 
+func (g MultiLineString) getLineString(index int) LineString {
+	if index < len(g.linestrings) {
+		return g.linestrings[index]
+	}
+	return LineString{Coordinates: g.Coordinates[index]}
+}
+
 // WithinBBox detects if the object is fully contained inside a bbox.
 func (g MultiLineString) WithinBBox(bbox BBox) bool {
 	if g.bboxDefined {
@@ -101,15 +125,10 @@ func (g MultiLineString) WithinBBox(bbox BBox) bool {
 	if len(g.Coordinates) == 0 {
 		return false
 	}
-	for _, ls := range g.Coordinates {
-		if len(ls) == 0 {
+	for i := range g.Coordinates {
+		if !g.getLineString(i).WithinBBox(bbox) {
 			return false
 		}
-		for _, p := range ls {
-			if !poly.Point(p).InsideRect(rectBBox(bbox)) {
-				return false
-			}
-		}
 	}
 	return true
 }
@@ -119,8 +138,8 @@ func (g MultiLineString) IntersectsBBox(bbox BBox) bool {
 	if g.bboxDefined {
 		return rectBBox(g.CalculatedBBox()).IntersectsRect(rectBBox(bbox))
 	}
-	for _, ls := range g.Coordinates {
-		if polyPositions(ls).IntersectsRect(rectBBox(bbox)) {
+	for i := range g.Coordinates {
+		if g.getLineString(i).IntersectsBBox(bbox) {
 			return true
 		}
 	}
@@ -129,36 +148,12 @@ func (g MultiLineString) IntersectsBBox(bbox BBox) bool {
 
 // Within detects if the object is fully contained inside another object.
 func (g MultiLineString) Within(o Object) bool {
-	return withinObjectShared(g, o,
-		func(v Polygon) bool {
-			if len(g.Coordinates) == 0 {
-				return false
-			}
-			for _, ls := range g.Coordinates {
-				if !polyPositions(ls).Inside(polyExteriorHoles(v.Coordinates)) {
-					return false
-				}
-			}
-			return true
-		},
-	)
+	return withinObjectShared(g, o)
 }
 
 // Intersects detects if the object intersects another object.
 func (g MultiLineString) Intersects(o Object) bool {
-	return intersectsObjectShared(g, o,
-		func(v Polygon) bool {
-			if len(g.Coordinates) == 0 {
-				return false
-			}
-			for _, ls := range g.Coordinates {
-				if polyPositions(ls).Intersects(polyExteriorHoles(v.Coordinates)) {
-					return true
-				}
-			}
-			return false
-		},
-	)
+	return intersectsObjectShared(g, o)
 }
 
 // Nearby detects if the object is nearby a position.

geojson/multipoint.go

@@ -25,6 +25,10 @@ func fillMultiPoint(coordinates []Position, bbox *BBox, err error) (MultiPoint,
 	}, err
 }
 
+func (g MultiPoint) getPoint(index int) Point {
+	return Point{Coordinates: g.Coordinates[index]}
+}
+
 // CalculatedBBox is exterior bbox containing the object.
 func (g MultiPoint) CalculatedBBox() BBox {
 	return level2CalculatedBBox(g.Coordinates, g.BBox)
@@ -108,36 +112,12 @@ func (g MultiPoint) IntersectsBBox(bbox BBox) bool {
 
 // Within detects if the object is fully contained inside another object.
 func (g MultiPoint) Within(o Object) bool {
-	return withinObjectShared(g, o,
-		func(v Polygon) bool {
-			if len(g.Coordinates) == 0 {
-				return false
-			}
-			for _, p := range g.Coordinates {
-				if !poly.Point(p).Inside(polyExteriorHoles(v.Coordinates)) {
-					return false
-				}
-			}
-			return true
-		},
-	)
+	return withinObjectShared(g, o)
 }
 
 // Intersects detects if the object intersects another object.
 func (g MultiPoint) Intersects(o Object) bool {
-	return intersectsObjectShared(g, o,
-		func(v Polygon) bool {
-			if len(g.Coordinates) == 0 {
-				return false
-			}
-			for _, p := range g.Coordinates {
-				if poly.Point(p).Intersects(polyExteriorHoles(v.Coordinates)) {
-					return true
-				}
-			}
-			return true
-		},
-	)
+	return intersectsObjectShared(g, o)
 }
 
 // Nearby detects if the object is nearby a position.

geojson/multipolygon.go

@@ -22,7 +22,7 @@ func fillMultiPolygon(coordinates [][][]Position, bbox *BBox, err error) (MultiP
 	}
 	bboxDefined := bbox != nil
 	if !bboxDefined {
-		cbbox := calculatedBBox(polygons, nil)
+		cbbox := mpCalculatedBBox(polygons, nil)
 		bbox = &cbbox
 	}
 	return MultiPolygon{
@@ -33,16 +33,16 @@ func fillMultiPolygon(coordinates [][][]Position, bbox *BBox, err error) (MultiP
 	}, err
 }
 
-func calculatedBBox(polygons []Polygon, bbox *BBox) BBox {
+func mpCalculatedBBox(polygons []Polygon, bbox *BBox) BBox {
 	if bbox != nil {
 		return *bbox
 	}
 	var cbbox BBox
-	for i, p := range polygons {
+	for i, g := range polygons {
 		if i == 0 {
-			cbbox = p.CalculatedBBox()
+			cbbox = g.CalculatedBBox()
 		} else {
-			cbbox = cbbox.union(p.CalculatedBBox())
+			cbbox = cbbox.union(g.CalculatedBBox())
 		}
 	}
 	return cbbox
@@ -50,7 +50,7 @@ func calculatedBBox(polygons []Polygon, bbox *BBox) BBox {
 
 // CalculatedBBox is exterior bbox containing the object.
 func (g MultiPolygon) CalculatedBBox() BBox {
-	return calculatedBBox(g.polygons, g.BBox)
+	return mpCalculatedBBox(g.polygons, g.BBox)
 }
 
 // CalculatedPoint is a point representation of the object.
@@ -148,32 +148,12 @@ func (g MultiPolygon) IntersectsBBox(bbox BBox) bool {
 
 // Within detects if the object is fully contained inside another object.
 func (g MultiPolygon) Within(o Object) bool {
-	return withinObjectShared(g, o,
-		func(v Polygon) bool {
-			if len(g.Coordinates) == 0 {
-				return false
-			}
-			if !v.Within(o) {
-				return false
-			}
-			return true
-		},
-	)
+	return withinObjectShared(g, o)
 }
 
 // Intersects detects if the object intersects another object.
 func (g MultiPolygon) Intersects(o Object) bool {
-	return intersectsObjectShared(g, o,
-		func(v Polygon) bool {
-			if len(g.Coordinates) == 0 {
-				return false
-			}
-			if v.Intersects(o) {
-				return true
-			}
-			return false
-		},
-	)
+	return intersectsObjectShared(g, o)
 }
 
 // Nearby detects if the object is nearby a position.

geojson/object.go

@@ -182,114 +182,6 @@ func objectMap(json string, from int) (Object, error) {
 	return o, err
 }
 
-func withinObjectShared(g Object, o Object, pin func(v Polygon) bool) bool {
-	bbp := o.bboxPtr()
-	if bbp != nil {
-		if !g.WithinBBox(*bbp) {
-			return false
-		}
-		if o.IsBBoxDefined() {
-			return true
-		}
-	}
-	switch v := o.(type) {
-	default:
-		return false
-	case Point:
-		return g.WithinBBox(v.CalculatedBBox())
-	case SimplePoint:
-		return g.WithinBBox(v.CalculatedBBox())
-	case Polygon:
-		if len(v.Coordinates) == 0 {
-			return false
-		}
-		return pin(v)
-	case MultiPolygon:
-		for i := range v.Coordinates {
-			if pin(v.getPolygon(i)) {
-				return true
-			}
-		}
-		return false
-	case Feature:
-		return g.Within(v.Geometry)
-	case FeatureCollection:
-		if len(v.Features) == 0 {
-			return false
-		}
-		for _, f := range v.Features {
-			if !g.Within(f) {
-				return false
-			}
-		}
-		return true
-	case GeometryCollection:
-		if len(v.Geometries) == 0 {
-			return false
-		}
-		for _, f := range v.Geometries {
-			if !g.Within(f) {
-				return false
-			}
-		}
-		return true
-	}
-}
-
-func intersectsObjectShared(g Object, o Object, pin func(v Polygon) bool) bool {
-	bbp := o.bboxPtr()
-	if bbp != nil {
-		if !g.IntersectsBBox(*bbp) {
-			return false
-		}
-		if o.IsBBoxDefined() {
-			return true
-		}
-	}
-	switch v := o.(type) {
-	default:
-		return false
-	case Point:
-		return g.IntersectsBBox(v.CalculatedBBox())
-	case SimplePoint:
-		return g.IntersectsBBox(v.CalculatedBBox())
-	case Polygon:
-		if len(v.Coordinates) == 0 {
-			return false
-		}
-		return pin(v)
-	case MultiPolygon:
-		for _, coords := range v.Coordinates {
-			if pin(Polygon{Coordinates: coords}) {
-				return true
-			}
-		}
-		return false
-	case Feature:
-		return g.Intersects(v.Geometry)
-	case FeatureCollection:
-		if len(v.Features) == 0 {
-			return false
-		}
-		for _, f := range v.Features {
-			if g.Intersects(f) {
-				return true
-			}
-		}
-		return false
-	case GeometryCollection:
-		if len(v.Geometries) == 0 {
-			return false
-		}
-		for _, f := range v.Geometries {
-			if g.Intersects(f) {
-				return true
-			}
-		}
-		return false
-	}
-}
-
 // CirclePolygon returns a Polygon around the radius.
 func CirclePolygon(x, y, meters float64, steps int) Polygon {
 	if steps < 3 {
@@ -310,21 +202,6 @@ func CirclePolygon(x, y, meters float64, steps int) Polygon {
 	return p
 }
 
-// The object's calculated bounding box must intersect the radius of the circle to pass.
-func nearbyObjectShared(g Object, x, y float64, meters float64) bool {
-	if !g.hasPositions() {
-		return false
-	}
-	center := Position{X: x, Y: y, Z: 0}
-	bbox := g.CalculatedBBox()
-	if bbox.Min.X == bbox.Max.X && bbox.Min.Y == bbox.Max.Y {
-		// just a point, return is point is inside of the circle
-		return center.DistanceTo(bbox.Min) <= meters
-	}
-	circlePoly := CirclePolygon(x, y, meters, 12)
-	return g.Intersects(circlePoly)
-}
-
 func jsonMarshalString(s string) []byte {
 	for i := 0; i < len(s); i++ {
 		if s[i] < ' ' || s[i] == '\\' || s[i] == '"' || s[i] > 126 {

geojson/object_test.go

@@ -42,3 +42,72 @@ func TestCirclePolygon(t *testing.T) {
 		t.Fatal("should intersect")
 	}
 }
+
+func TestIssue281(t *testing.T) {
+	p := testJSON(t, `{"type":"Polygon","coordinates":[[
+		[-74.008283,40.718249],
+		[-74.007339,40.713305],
+		[-73.999013,40.714866],
+		[-74.001760,40.720851],
+		[-74.008283,40.718249]
+	]]}`)
+
+	// intersects polygon
+	ls1 := testJSON(t, `{"type":"LineString","coordinates":[
+		[-74.003648,40.717533],
+		[-73.99575233459473,40.72046126415031],
+		[-73.99721145629883,40.72338850378556]
+	]}`)
+
+	// outside polygon
+	ls2 := testJSON(t, `{"type":"LineString","coordinates":[
+		[-74.007682,40.722998],
+		[-74.001932,40.728462],
+		[-74.001846,40.723583]
+	]}`)
+
+	// inside polygon
+	ls3 := testJSON(t, `{"type":"LineString","coordinates":[
+          [-74.006910,40.717598],
+          [-74.006137,40.715387],
+          [-74.001331,40.715907]
+        ]}`)
+
+	if !ls1.Intersects(p) {
+		t.Fatalf("expected true")
+	}
+	if !p.Intersects(ls1) {
+		t.Fatalf("expected true")
+	}
+	if ls1.Within(p) {
+		t.Fatalf("expected false")
+	}
+	if p.Within(ls1) {
+		t.Fatalf("expected false")
+	}
+	if ls2.Intersects(p) {
+		t.Fatalf("expected false")
+	}
+	if p.Intersects(ls2) {
+		t.Fatalf("expected false")
+	}
+	if ls2.Within(p) {
+		t.Fatalf("expected false")
+	}
+	if p.Within(ls2) {
+		t.Fatalf("expected false")
+	}
+	if !ls3.Intersects(p) {
+		t.Fatalf("expected true")
+	}
+	if !p.Intersects(ls3) {
+		t.Fatalf("expected true")
+	}
+	if !ls3.Within(p) {
+		t.Fatalf("expected true")
+	}
+	if p.Within(ls3) {
+		t.Fatalf("expected false")
+	}
+
+}

geojson/point.go

@@ -105,20 +105,12 @@ func (g Point) IntersectsBBox(bbox BBox) bool {
 
 // Within detects if the object is fully contained inside another object.
 func (g Point) Within(o Object) bool {
-	return withinObjectShared(g, o,
-		func(v Polygon) bool {
-			return poly.Point(g.Coordinates).Inside(polyExteriorHoles(v.Coordinates))
-		},
-	)
+	return withinObjectShared(g, o)
 }
 
 // Intersects detects if the object intersects another object.
 func (g Point) Intersects(o Object) bool {
-	return intersectsObjectShared(g, o,
-		func(v Polygon) bool {
-			return poly.Point(g.Coordinates).Intersects(polyExteriorHoles(v.Coordinates))
-		},
-	)
+	return intersectsObjectShared(g, o)
 }
 
 // Nearby detects if the object is nearby a position.

geojson/poly/intersects.go

@@ -1,5 +1,15 @@
 package poly
 
+// IntersectsLineString detect if a point intersects a linestring
+func (p Point) IntersectsLineString(exterior Polygon) bool {
+	for j := 0; j < len(exterior); j++ {
+		if raycast(p, exterior[j], exterior[(j+1)%len(exterior)]).on {
+			return true
+		}
+	}
+	return false
+}
+
 // Intersects detects if a point intersects another polygon
 func (p Point) Intersects(exterior Polygon, holes []Polygon) bool {
 	return p.Inside(exterior, holes)
@@ -7,7 +17,7 @@ func (p Point) Intersects(exterior Polygon, holes []Polygon) bool {
 
 // Intersects detects if a rect intersects another polygon
 func (r Rect) Intersects(exterior Polygon, holes []Polygon) bool {
-	return r.Polygon().Inside(exterior, holes)
+	return r.Polygon().Intersects(exterior, holes)
 }
 
 // Intersects detects if a polygon intersects another polygon
@@ -15,7 +25,24 @@ func (shape Polygon) Intersects(exterior Polygon, holes []Polygon) bool {
 	return shape.doesIntersects(false, exterior, holes)
 }
 
+// LineStringIntersectsLineString detects if a linestring intersects a linestring
+// assume shape and exterior are actually linestrings
+func (shape Polygon) LineStringIntersectsLineString(exterior Polygon) bool {
+	for i := 0; i < len(shape); i++ {
+		for j := 0; j < len(exterior); j++ {
+			if lineintersects(
+				shape[i], shape[(i+1)%len(shape)],
+				exterior[j], exterior[(j+1)%len(exterior)],
+			) {
+				return true
+			}
+		}
+	}
+	return false
+}
+
 // LineStringIntersects detects if a polygon intersects a linestring
+// assume shape is a linestring
 func (shape Polygon) LineStringIntersects(exterior Polygon, holes []Polygon) bool {
 	return shape.doesIntersects(true, exterior, holes)
 }

geojson/polygon.go

@@ -145,26 +145,12 @@ func (g Polygon) IntersectsBBox(bbox BBox) bool {
 
 // Within detects if the object is fully contained inside another object.
 func (g Polygon) Within(o Object) bool {
-	return withinObjectShared(g, o,
-		func(v Polygon) bool {
-			if len(g.Coordinates) == 0 {
-				return false
-			}
-			return polyPositions(g.Coordinates[0]).Inside(polyExteriorHoles(v.Coordinates))
-		},
-	)
+	return withinObjectShared(g, o)
 }
 
 // Intersects detects if the object intersects another object.
 func (g Polygon) Intersects(o Object) bool {
-	return intersectsObjectShared(g, o,
-		func(v Polygon) bool {
-			if len(g.Coordinates) == 0 {
-				return false
-			}
-			return polyPositions(g.Coordinates[0]).Intersects(polyExteriorHoles(v.Coordinates))
-		},
-	)
+	return intersectsObjectShared(g, o)
 }
 
 // Nearby detects if the object is nearby a position.

geojson/simplepoint.go

@@ -87,20 +87,12 @@ func (g SimplePoint) IntersectsBBox(bbox BBox) bool {
 
 // Within detects if the object is fully contained inside another object.
 func (g SimplePoint) Within(o Object) bool {
-	return withinObjectShared(g, o,
-		func(v Polygon) bool {
-			return poly.Point(Position{X: g.X, Y: g.Y, Z: 0}).Inside(polyExteriorHoles(v.Coordinates))
-		},
-	)
+	return withinObjectShared(g, o)
 }
 
 // Intersects detects if the object intersects another object.
 func (g SimplePoint) Intersects(o Object) bool {
-	return intersectsObjectShared(g, o,
-		func(v Polygon) bool {
-			return poly.Point(Position{X: g.X, Y: g.Y, Z: 0}).Intersects(polyExteriorHoles(v.Coordinates))
-		},
-	)
+	return intersectsObjectShared(g, o)
 }
 
 // Nearby detects if the object is nearby a position.