Removing "earth" overlap from S2 tests

s2/contains_point_query_test.go

@@ -138,7 +138,7 @@ func TestContainsPointQueryVertexModelClosed(t *testing.T) {
 
 func TestContainsPointQueryContainingShapes(t *testing.T) {
 	const numVerticesPerLoop = 10
-	maxLoopRadius := kmToAngle(10)
+	maxLoopRadius := testRadiusMedium
 	centerCap := CapFromCenterAngle(randomPoint(), maxLoopRadius)
 	index := NewShapeIndex()
 

s2/edge_distances_test.go

@@ -867,7 +867,7 @@ func TestEdgeDistancesEdgePairMaxDistance(t *testing.T) {
 func TestEdgeDistancesPointToLeft(t *testing.T) {
 	a := PointFromLatLng(LatLngFromDegrees(0, 0))
 	b := PointFromLatLng(LatLngFromDegrees(0, 5)) // east
-	dist := kmToAngle(10 / 1000.0)
+	dist := testRadiusSmall
 
 	c := PointToLeft(a, b, dist)
 	if got := a.Distance(c).Radians(); !float64Near(got, dist.Radians(), epsilon) {
@@ -882,7 +882,7 @@ func TestEdgeDistancesPointToLeft(t *testing.T) {
 func TestEdgeDistancesPointToRight(t *testing.T) {
 	a := PointFromLatLng(LatLngFromDegrees(0, 0))
 	b := PointFromLatLng(LatLngFromDegrees(0, 5)) // east
-	dist := kmToAngle(10 / 1000.0)
+	dist := testRadiusSmall
 
 	c := PointToRight(a, b, dist)
 	if got := a.Distance(c).Radians(); !float64Near(got, dist.Radians(), epsilon) {

s2/edge_query_closest_test.go

@@ -238,7 +238,7 @@ func BenchmarkEdgeQueryFindEdges(b *testing.B) {
 				targetType:               queryTypePoint,
 				numTargetEdges:           0,
 				chooseTargetFromIndex:    false,
-				radiusKm:                 1000,
+				radius:                   testRadiusLarge,
 				maxDistanceFraction:      -1,
 				maxErrorFraction:         -1,
 				targetRadiusFraction:     0.0,
@@ -254,7 +254,7 @@ func BenchmarkEdgeQueryFindEdges(b *testing.B) {
 				targetType:               queryTypePoint,
 				numTargetEdges:           0,
 				chooseTargetFromIndex:    false,
-				radiusKm:                 1000,
+				radius:                   testRadiusLarge,
 				maxDistanceFraction:      -1,
 				maxErrorFraction:         -1,
 				targetRadiusFraction:     0.0,
@@ -271,7 +271,7 @@ func BenchmarkEdgeQueryFindEdges(b *testing.B) {
 				targetType:               queryTypePoint,
 				numTargetEdges:           0,
 				chooseTargetFromIndex:    false,
-				radiusKm:                 1000,
+				radius:                   testRadiusLarge,
 				maxDistanceFraction:      -1,
 				maxErrorFraction:         0.1,
 				targetRadiusFraction:     0.0,
@@ -288,7 +288,7 @@ func BenchmarkEdgeQueryFindEdges(b *testing.B) {
 				targetType:               queryTypePoint,
 				numTargetEdges:           0,
 				chooseTargetFromIndex:    false,
-				radiusKm:                 1000,
+				radius:                   testRadiusLarge,
 				maxDistanceFraction:      -1,
 				maxErrorFraction:         0.01,
 				targetRadiusFraction:     0.0,
@@ -302,7 +302,7 @@ func BenchmarkEdgeQueryFindEdges(b *testing.B) {
 				targetType:               queryTypeEdge,
 				numTargetEdges:           0,
 				chooseTargetFromIndex:    false,
-				radiusKm:                 1000,
+				radius:                   testRadiusLarge,
 				maxDistanceFraction:      -1,
 				maxErrorFraction:         -1,
 				targetRadiusFraction:     -1.0,
@@ -316,7 +316,7 @@ func BenchmarkEdgeQueryFindEdges(b *testing.B) {
 				targetType:               queryTypeCell,
 				numTargetEdges:           0,
 				chooseTargetFromIndex:    false,
-				radiusKm:                 1000,
+				radius:                   testRadiusLarge,
 				maxDistanceFraction:      -1,
 				maxErrorFraction:         -1,
 				targetRadiusFraction:     -1.0,

s2/edge_query_test.go

@@ -222,8 +222,8 @@ const edgeQueryTestNumIndexes = 50
 const edgeQueryTestNumEdges = 100
 const edgeQueryTestNumQueries = 200
 
-// The approximate radius of Cap from which query edges are chosen.
-var testCapRadius = kmToAngle(10)
+// testCapRadius is the angular radius of the Cap from which query edges are chosen.
+var testCapRadius = testRadiusMedium
 
 /*
 // testEdgeQueryWithGenerator is used to perform high volume random testing on EdqeQuery
@@ -340,7 +340,7 @@ func benchmarkEdgeQueryFindClosest(b *testing.B, bmOpts *edgeQueryBenchmarkOptio
 	index := NewShapeIndex()
 	opts := NewClosestEdgeQueryOptions().MaxResults(1).IncludeInteriors(bmOpts.includeInteriors)
 
-	radius := kmToAngle(bmOpts.radiusKm.Radians())
+	radius := bmOpts.radius
 	if bmOpts.maxDistanceFraction > 0 {
 		opts.DistanceLimit(s1.ChordAngleFromAngle(s1.Angle(bmOpts.maxDistanceFraction) * radius))
 	}
@@ -389,7 +389,7 @@ type edgeQueryBenchmarkOptions struct {
 	targetType               queryTargetType
 	numTargetEdges           int
 	chooseTargetFromIndex    bool
-	radiusKm                 s1.Angle
+	radius                   s1.Angle
 	maxDistanceFraction      float64
 	maxErrorFraction         float64
 	targetRadiusFraction     float64
@@ -402,7 +402,7 @@ type edgeQueryBenchmarkOptions struct {
 //
 // Approximately numIndexEdges will be generated by the requested generator and
 // inserted. The geometry is generated within a Cap of the radius specified
-// by radiusKm (the index radius). Parameters with fraction in their
+// by radius (the index radius). Parameters with fraction in their
 // names are expressed as a fraction of this radius.
 //
 // Also generates a set of target geometries for the query, based on the
@@ -436,7 +436,7 @@ func generateEdgeQueryWithTargets(opts *edgeQueryBenchmarkOptions, query *EdgeQu
 	// Replace with r := rand.New(rand.NewSource(opts.randomSeed)) and pass through.
 	r := rand.New(rand.NewSource(opts.randomSeed))
 	opts.randomSeed++
-	indexCap := CapFromCenterAngle(randomPoint(r), opts.radiusKm)
+	indexCap := CapFromCenterAngle(randomPoint(r), opts.radius)
 
 	query.Reset()
 	queryIndex.Reset()
@@ -452,10 +452,10 @@ func generateEdgeQueryWithTargets(opts *edgeQueryBenchmarkOptions, query *EdgeQu
 	}
 
 	for i := 0; i < numTargets; i++ {
-		targetDist := fractionToRadius(opts.centerSeparationFraction, opts.radiusKm.Radians())
+		targetDist := fractionToRadius(opts.centerSeparationFraction, opts.radius)
 		targetCap := CapFromCenterAngle(
 			sampleBoundaryFromCap(CapFromCenterAngle(indexCap.Center(), targetDist)),
-			fractionToRadius(opts.targetRadiusFraction, opts.radiusKm.Radians()))
+			fractionToRadius(opts.targetRadiusFraction, opts.radius))
 
 		switch opts.targetType {
 		case queryTypePoint:
@@ -535,9 +535,9 @@ func sampleCellFromIndex(index *ShapeIndex) CellID {
 	return iter.CellID()
 }
 
-func fractionToRadius(fraction, radiusKm float64) s1.Angle {
+func fractionToRadius(fraction float64, radius s1.Angle) s1.Angle {
 	if fraction < 0 {
 		fraction = -randomFloat64() * fraction
 	}
-	return s1.Angle(fraction) * kmToAngle(radiusKm)
+	return s1.Angle(fraction) * radius
 }

s2/loop_test.go

@@ -1864,7 +1864,7 @@ func BenchmarkLoopContainsPoint(b *testing.B) {
 				b.StopTimer()
 				loops := make([]*Loop, numLoopSamples)
 				for i := range numLoopSamples {
-					loops[i] = RegularLoop(randomPoint(), kmToAngle(10.0), vertices)
+					loops[i] = RegularLoop(randomPoint(), testRadiusMedium, vertices)
 				}
 
 				queries := make([][]Point, numLoopSamples)

s2/point_test.go

@@ -45,8 +45,11 @@ func TestOriginPoint(t *testing.T) {
 	}
 
 	// Check that the origin is not too close to either pole.
-	if dist := math.Acos(OriginPoint().Z) * earthRadiusKm; dist <= 50 {
-		t.Errorf("Origin point is to close to the North Pole. Got %v, want >= 50km", dist)
+	// The threshold of 0.45 degrees (~50km on Earth-scale sphere) ensures the origin
+	// is far enough from poles for numerical stability in tests.
+	minAngleFromPole := 0.45 * s1.Degree
+	if angle := s1.Angle(math.Acos(OriginPoint().Z)); angle <= minAngleFromPole {
+		t.Errorf("Origin point is too close to the North Pole. Got %v, want > %v", angle, minAngleFromPole)
 	}
 }
 

s2/pointcompression_test.go

@@ -33,9 +33,9 @@ func TestFacesIterator(t *testing.T) {
 }
 
 func makeSnappedPoints(nvertices int, level int) []Point {
-	const radiusKM = 0.1
+	radius := testRadiusSmall
 	center := PointFromCoords(1, 1, 1)
-	pts := regularPoints(center, kmToAngle(radiusKM), nvertices)
+	pts := regularPoints(center, radius, nvertices)
 	for i, pt := range pts {
 		id := CellFromPoint(pt).ID()
 		if level < id.Level() {

s2/polygon_test.go

@@ -1144,7 +1144,7 @@ func TestPolygonInvert(t *testing.T) {
 	origin := PointFromLatLng(LatLngFromDegrees(0, 0))
 	pt := PointFromLatLng(LatLngFromDegrees(30, 30))
 	p := PolygonFromLoops([]*Loop{
-		RegularLoop(origin, 1000/earthRadiusKm, 100),
+		RegularLoop(origin, testRadiusLarge, 100),
 	})
 
 	if p.ContainsPoint(pt) {

s2/predicates_test.go

@@ -305,7 +305,10 @@ func TestPredicatesStableSignFailureRate(t *testing.T) {
 	// that are as collinear as possible and spaced the given distance apart
 	// by counting up the times it returns Indeterminate.
 	failureCount := 0
-	m := math.Tan(spacing / earthRadiusKm)
+	// The spacing factor determines how far apart the near-collinear test points are.
+	// Original used 1km spacing on Earth-scale sphere (~0.009 degrees).
+	spacingAngle := 0.009 * s1.Degree
+	m := math.Tan(spacingAngle.Radians() * spacing)
 	for range iters {
 		f := randomFrame()
 		a := f.col(0)

s2/regioncoverer_test.go

@@ -337,7 +337,7 @@ func BenchmarkRegionCovererCoveringLoop(b *testing.B) {
 			size := int(math.Pow(2.0, float64(n)))
 			regions := make([]Region, numCoveringBMRegions)
 			for i := range numCoveringBMRegions {
-				regions[i] = RegularLoop(randomPoint(), kmToAngle(10.0), size)
+				regions[i] = RegularLoop(randomPoint(), testRadiusMedium, size)
 			}
 			return regions
 		})

s2/s2_test.go

@@ -74,13 +74,19 @@ func float64Near(x, y, ε float64) bool {
 	return math.Abs(x-y) <= ε
 }
 
-// The Earth's mean radius in kilometers (according to NASA).
-const earthRadiusKm = 6371.01
+const (
+	// testRadiusSmall is approximately 1km on a unit sphere scaled to Earth size.
+	// Used for tests needing very small distances (e.g., point offset tests).
+	testRadiusSmall = 9e-5 * s1.Degree // ~10 meters
 
-// kmToAngle converts a distance on the Earth's surface to an angle.
-func kmToAngle(km float64) s1.Angle {
-	return s1.Angle(km / earthRadiusKm)
-}
+	// testRadiusMedium is approximately 10km on a unit sphere scaled to Earth size.
+	// Used for most geometry tests (containment, edge queries, etc.).
+	testRadiusMedium = 0.09 * s1.Degree // ~10 km
+
+	// testRadiusLarge is approximately 1000km on a unit sphere scaled to Earth size.
+	// Used for tests needing larger regions (polygon inversion, etc.).
+	testRadiusLarge = 9 * s1.Degree // ~1000 km
+)
 
 // randomBits returns a 64-bit random unsigned integer whose lowest "num" are random, and
 // whose other bits are zero.

s2/s2_test_test.go

@@ -22,25 +22,6 @@ import (
 	"github.com/golang/geo/s1"
 )
 
-func TestKmToAngle(t *testing.T) {
-	tests := []struct {
-		have float64
-		want s1.Angle
-	}{
-		{0.0, 0.0},
-		{1.0, 0.00015696098420815537 * s1.Radian},
-		{earthRadiusKm, 1.0 * s1.Radian},
-		{-1.0, -0.00015696098420815537 * s1.Radian},
-		{-10000.0, -1.5696098420815536300 * s1.Radian},
-		{1e9, 156960.984208155363007 * s1.Radian},
-	}
-	for _, test := range tests {
-		if got := kmToAngle(test.have); !float64Eq(float64(got), float64(test.want)) {
-			t.Errorf("kmToAngle(%f) = %0.20f, want %0.20f", test.have, got, test.want)
-		}
-	}
-}
-
 func numVerticesAtLevel(level int) int {
 	// Sanity / overflow check
 	if level < 0 || level > 14 {