diff options
Diffstat (limited to 'vendor/github.com/golang/geo/s2/latlng_test.go')
| -rw-r--r-- | vendor/github.com/golang/geo/s2/latlng_test.go | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/vendor/github.com/golang/geo/s2/latlng_test.go b/vendor/github.com/golang/geo/s2/latlng_test.go new file mode 100644 index 0000000..54f96f8 --- /dev/null +++ b/vendor/github.com/golang/geo/s2/latlng_test.go @@ -0,0 +1,155 @@ +/* +Copyright 2014 Google Inc. All rights reserved. + +Licensed under the Apache License, Version 2.0 (the "License"); +you may not use this file except in compliance with the License. +You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, software +distributed under the License is distributed on an "AS IS" BASIS, +WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +See the License for the specific language governing permissions and +limitations under the License. +*/ + +package s2 + +import ( + "math" + "testing" + + "github.com/golang/geo/s1" +) + +func TestLatLngNormalized(t *testing.T) { + tests := []struct { + desc string + pos LatLng + want LatLng + }{ + { + desc: "Valid lat/lng", + pos: LatLngFromDegrees(21.8275043, 151.1979675), + want: LatLngFromDegrees(21.8275043, 151.1979675), + }, + { + desc: "Valid lat/lng in the West", + pos: LatLngFromDegrees(21.8275043, -151.1979675), + want: LatLngFromDegrees(21.8275043, -151.1979675), + }, + { + desc: "Beyond the North pole", + pos: LatLngFromDegrees(95, 151.1979675), + want: LatLngFromDegrees(90, 151.1979675), + }, + { + desc: "Beyond the South pole", + pos: LatLngFromDegrees(-95, 151.1979675), + want: LatLngFromDegrees(-90, 151.1979675), + }, + { + desc: "At the date line (from East)", + pos: LatLngFromDegrees(21.8275043, 180), + want: LatLngFromDegrees(21.8275043, 180), + }, + { + desc: "At the date line (from West)", + pos: LatLngFromDegrees(21.8275043, -180), + want: LatLngFromDegrees(21.8275043, -180), + }, + { + desc: "Across the date line going East", + pos: LatLngFromDegrees(21.8275043, 181.0012), + want: LatLngFromDegrees(21.8275043, -178.9988), + }, + { + desc: "Across the date line going West", + pos: LatLngFromDegrees(21.8275043, -181.0012), + want: LatLngFromDegrees(21.8275043, 178.9988), + }, + { + desc: "All wrong", + pos: LatLngFromDegrees(256, 256), + want: LatLngFromDegrees(90, -104), + }, + } + + for _, test := range tests { + got := test.pos.Normalized() + if !got.IsValid() { + t.Errorf("%s: A LatLng should be valid after normalization but isn't: %v", test.desc, got) + } else if got.Distance(test.want) > 1e-13*s1.Degree { + t.Errorf("%s: %v.Normalized() = %v, want %v", test.desc, test.pos, got, test.want) + } + } +} + +func TestLatLngString(t *testing.T) { + const expected string = "[1.4142136, -2.2360680]" + s := LatLngFromDegrees(math.Sqrt2, -math.Sqrt(5)).String() + if s != expected { + t.Errorf("LatLng{√2, -√5}.String() = %q, want %q", s, expected) + } +} + +func TestLatLngPointConversion(t *testing.T) { + // All test cases here have been verified against the C++ S2 implementation. + tests := []struct { + lat, lng float64 // degrees + x, y, z float64 + }{ + {0, 0, 1, 0, 0}, + {90, 0, 6.12323e-17, 0, 1}, + {-90, 0, 6.12323e-17, 0, -1}, + {0, 180, -1, 1.22465e-16, 0}, + {0, -180, -1, -1.22465e-16, 0}, + {90, 180, -6.12323e-17, 7.4988e-33, 1}, + {90, -180, -6.12323e-17, -7.4988e-33, 1}, + {-90, 180, -6.12323e-17, 7.4988e-33, -1}, + {-90, -180, -6.12323e-17, -7.4988e-33, -1}, + {-81.82750430354997, 151.19796752929685, + -0.12456788151479525, 0.0684875268284729, -0.989844584550441}, + } + for _, test := range tests { + ll := LatLngFromDegrees(test.lat, test.lng) + p := PointFromLatLng(ll) + // TODO(mikeperrow): Port Point.ApproxEquals, then use here. + if !float64Eq(p.X, test.x) || !float64Eq(p.Y, test.y) || !float64Eq(p.Z, test.z) { + t.Errorf("PointFromLatLng({%v°, %v°}) = %v, want %v, %v, %v", + test.lat, test.lng, p, test.x, test.y, test.z) + } + ll = LatLngFromPoint(p) + // We need to be careful here, since if the latitude is +/- 90, any longitude + // is now a valid conversion. + isPolar := (test.lat == 90 || test.lat == -90) + if !float64Eq(ll.Lat.Degrees(), test.lat) || + (!isPolar && (!float64Eq(ll.Lng.Degrees(), test.lng))) { + t.Errorf("Converting ll %v,%v to point (%v) and back gave %v.", + test.lat, test.lng, p, ll) + } + } +} + +func TestLatLngDistance(t *testing.T) { + // Based on C++ S2LatLng::TestDistance. + tests := []struct { + lat1, lng1, lat2, lng2 float64 + want, tolerance float64 + }{ + {90, 0, 90, 0, 0, 0}, + {-37, 25, -66, -155, 77, 1e-13}, + {0, 165, 0, -80, 115, 1e-13}, + {47, -127, -47, 53, 180, 2e-6}, + } + for _, test := range tests { + ll1 := LatLngFromDegrees(test.lat1, test.lng1) + ll2 := LatLngFromDegrees(test.lat2, test.lng2) + d := ll1.Distance(ll2).Degrees() + if math.Abs(d-test.want) > test.tolerance { + t.Errorf("LatLng{%v, %v}.Distance(LatLng{%v, %v}).Degrees() = %v, want %v", + test.lat1, test.lng1, test.lat2, test.lng2, d, test.want) + } + } +} |