package orb

EarthRadius is the radius of the earth in meters. It is used in geo distance calculations. To keep things consistent, this value matches WGS84 Web Mercator (EPSG:3857).

Variables ¶

var AllGeometries = []Geometry{
	nil,
	Point{},
	MultiPoint{},
	LineString{},
	MultiLineString{},
	Ring{},
	Polygon{},
	MultiPolygon{},
	Bound{},
	Collection{},

	MultiPoint(nil),
	LineString(nil),
	MultiLineString(nil),
	Ring(nil),
	Polygon(nil),
	MultiPolygon(nil),
	Collection(nil),

	Collection{Collection{Point{}}},
}

AllGeometries lists all possible types and values that a geometry interface can be. It should be used only for testing to verify functions that accept a Geometry will work in all cases.

var DefaultRoundingFactor = 1e6 // 6 decimal places

DefaultRoundingFactor is the default rounding factor used by the Round func.

Functions ¶

func Equal ¶

func Equal(g1, g2 Geometry) bool

Equal returns if the two geometrires are equal.

Types ¶

type Bound ¶

type Bound struct {
	Min, Max Point
}

A Bound represents a closed box or rectangle. To create a bound with two points you can do something like:

orb.MultiPoint{p1, p2}.Bound()

func (Bound) Bottom ¶

func (b Bound) Bottom() float64

Bottom returns the bottom of the bound.

func (Bound) Bound ¶

func (b Bound) Bound() Bound

Bound returns the the same bound.

func (Bound) Center ¶

func (b Bound) Center() Point

Center returns the center of the bounds by "averaging" the x and y coords.

func (Bound) Contains ¶

func (b Bound) Contains(point Point) bool

Contains determines if the point is within the bound. Points on the boundary are considered within.

func (Bound) Dimensions ¶

func (b Bound) Dimensions() int

Dimensions returns 2 because a Bound is a 2d object.

func (Bound) Equal ¶

func (b Bound) Equal(c Bound) bool

Equal returns if two bounds are equal.

func (Bound) Extend ¶

func (b Bound) Extend(point Point) Bound

Extend grows the bound to include the new point.

func (Bound) GeoJSONType ¶

func (b Bound) GeoJSONType() string

GeoJSONType returns the GeoJSON type for the object.

func (Bound) Intersects ¶

func (b Bound) Intersects(bound Bound) bool

Intersects determines if two bounds intersect. Returns true if they are touching.

func (Bound) IsEmpty ¶

func (b Bound) IsEmpty() bool

IsEmpty returns true if it contains zero area or if it's in some malformed negative state where the left point is larger than the right. This can be caused by padding too much negative.

func (Bound) IsZero ¶

func (b Bound) IsZero() bool

IsZero return true if the bound just includes just null island.

func (Bound) Left ¶

func (b Bound) Left() float64

Left returns the left of the bound.

func (Bound) LeftTop ¶

func (b Bound) LeftTop() Point

LeftTop returns the upper left point of the bound.

func (Bound) Pad ¶

func (b Bound) Pad(d float64) Bound

Pad extends the bound in all directions by the given value.

func (Bound) Right ¶

func (b Bound) Right() float64

Right returns the right of the bound.

func (Bound) RightBottom ¶

func (b Bound) RightBottom() Point

RightBottom return the lower right point of the bound.

func (Bound) ToPolygon ¶

func (b Bound) ToPolygon() Polygon

ToPolygon converts the bound into a Polygon object.

func (Bound) ToRing ¶

func (b Bound) ToRing() Ring

ToRing converts the bound into a loop defined by the boundary of the box.

func (Bound) Top ¶

func (b Bound) Top() float64

Top returns the top of the bound.

func (Bound) Union ¶

func (b Bound) Union(other Bound) Bound

Union extends this bound to contain the union of this and the given bound.

type Collection ¶

type Collection []Geometry

A Collection is a collection of geometries that is also a Geometry.

func (Collection) Bound ¶

func (c Collection) Bound() Bound

Bound returns the bounding box of all the Geometries combined.

func (Collection) Clone ¶

func (c Collection) Clone() Collection

Clone returns a deep copy of the collection.

func (Collection) Dimensions ¶

func (c Collection) Dimensions() int

Dimensions returns the max of the dimensions of the collection.

func (Collection) Equal ¶

func (c Collection) Equal(collection Collection) bool

Equal compares two collections. Returns true if lengths are the same and all the sub geometries are the same and in the same order.

func (Collection) GeoJSONType ¶

func (c Collection) GeoJSONType() string

GeoJSONType returns the geometry collection type.

type DistanceFunc ¶

type DistanceFunc func(Point, Point) float64

A DistanceFunc is a function that computes the distance between two points.

type Geometry ¶

type Geometry interface {
	GeoJSONType() string
	Dimensions() int // e.g. 0d, 1d, 2d
	Bound() Bound
	// contains filtered or unexported methods
}

Geometry is an interface that represents the shared attributes of a geometry.

func Clone ¶

func Clone(g Geometry) Geometry

Clone will make a deep copy of the geometry.

func Round ¶

func Round(g Geometry, factor ...int) Geometry

Round will round all the coordinates of the geometry to the given factor. The default is 6 decimal places.

type LineString ¶

type LineString []Point

LineString represents a set of points to be thought of as a polyline.

func (LineString) Bound ¶

func (ls LineString) Bound() Bound

Bound returns a rect around the line string. Uses rectangular coordinates.

func (LineString) Clone ¶

func (ls LineString) Clone() LineString

Clone returns a new copy of the line string.

func (LineString) Dimensions ¶

func (ls LineString) Dimensions() int

Dimensions returns 1 because a LineString is a 1d object.

func (LineString) Equal ¶

func (ls LineString) Equal(lineString LineString) bool

Equal compares two line strings. Returns true if lengths are the same and all points are Equal.

func (LineString) GeoJSONType ¶

func (ls LineString) GeoJSONType() string

GeoJSONType returns the GeoJSON type for the object.

func (LineString) Reverse ¶

func (ls LineString) Reverse()

Reverse will reverse the line string. This is done inplace, ie. it modifies the original data.

type MultiLineString ¶

type MultiLineString []LineString

MultiLineString is a set of polylines.

func (MultiLineString) Bound ¶

func (mls MultiLineString) Bound() Bound

Bound returns a bound around all the line strings.

func (MultiLineString) Clone ¶

func (mls MultiLineString) Clone() MultiLineString

Clone returns a new deep copy of the multi line string.

func (MultiLineString) Dimensions ¶

func (mls MultiLineString) Dimensions() int

Dimensions returns 1 because a MultiLineString is a 2d object.

func (MultiLineString) Equal ¶

func (mls MultiLineString) Equal(multiLineString MultiLineString) bool

Equal compares two multi line strings. Returns true if lengths are the same and all points are Equal.

func (MultiLineString) GeoJSONType ¶

func (mls MultiLineString) GeoJSONType() string

GeoJSONType returns the GeoJSON type for the object.

type MultiPoint ¶

type MultiPoint []Point

A MultiPoint represents a set of points in the 2D Eucledian or Cartesian plane.

func (MultiPoint) Bound ¶

func (mp MultiPoint) Bound() Bound

Bound returns a bound around the points. Uses rectangular coordinates.

func (MultiPoint) Clone ¶

func (mp MultiPoint) Clone() MultiPoint

Clone returns a new copy of the points.

func (MultiPoint) Dimensions ¶

func (mp MultiPoint) Dimensions() int

Dimensions returns 0 because a MultiPoint is a 0d object.

func (MultiPoint) Equal ¶

func (mp MultiPoint) Equal(multiPoint MultiPoint) bool

Equal compares two MultiPoint objects. Returns true if lengths are the same and all points are Equal, and in the same order.

func (MultiPoint) GeoJSONType ¶

func (mp MultiPoint) GeoJSONType() string

GeoJSONType returns the GeoJSON type for the object.

type MultiPolygon ¶

type MultiPolygon []Polygon

MultiPolygon is a set of polygons.

func (MultiPolygon) Bound ¶

func (mp MultiPolygon) Bound() Bound

Bound returns a bound around the multi-polygon.

func (MultiPolygon) Clone ¶

func (mp MultiPolygon) Clone() MultiPolygon

Clone returns a new deep copy of the multi-polygon.

func (MultiPolygon) Dimensions ¶

func (mp MultiPolygon) Dimensions() int

Dimensions returns 2 because a MultiPolygon is a 2d object.

func (MultiPolygon) Equal ¶

func (mp MultiPolygon) Equal(multiPolygon MultiPolygon) bool

Equal compares two multi-polygons.

func (MultiPolygon) GeoJSONType ¶

func (mp MultiPolygon) GeoJSONType() string

GeoJSONType returns the GeoJSON type for the object.

type Orientation ¶

type Orientation int8

Orientation defines the order of the points in a polygon or closed ring.

const (
	// CCW stands for Counter Clock Wise
	CCW Orientation = 1

	// CW stands for Clock Wise
	CW Orientation = -1
)

Constants to define orientation. They follow the right hand rule for orientation.

type Point ¶

type Point [2]float64

A Point is a Lon/Lat 2d point.

func (Point) Bound ¶

func (p Point) Bound() Bound

Bound returns a single point bound of the point.

func (Point) Dimensions ¶

func (p Point) Dimensions() int

Dimensions returns 0 because a point is a 0d object.

func (Point) Equal ¶

func (p Point) Equal(point Point) bool

Equal checks if the point represents the same point or vector.

func (Point) GeoJSONType ¶

func (p Point) GeoJSONType() string

GeoJSONType returns the GeoJSON type for the object.

func (Point) Lat ¶

func (p Point) Lat() float64

Lat returns the vertical, latitude coordinate of the point.

func (Point) Lon ¶

func (p Point) Lon() float64

Lon returns the horizontal, longitude coordinate of the point.

func (Point) Point ¶

func (p Point) Point() Point

Point returns itself so it implements the Pointer interface.

func (Point) X ¶

func (p Point) X() float64

X returns the horizontal coordinate of the point.

func (Point) Y ¶

func (p Point) Y() float64

Y returns the vertical coordinate of the point.

type Pointer ¶

type Pointer interface {
	Point() Point
}

Pointer is something that can be represented by a point.

type Polygon ¶

type Polygon []Ring

Polygon is a closed area. The first LineString is the outer ring. The others are the holes. Each LineString is expected to be closed ie. the first point matches the last.

func (Polygon) Bound ¶

func (p Polygon) Bound() Bound

Bound returns a bound around the polygon.

func (Polygon) Clone ¶

func (p Polygon) Clone() Polygon

Clone returns a new deep copy of the polygon. All of the rings are also cloned.

func (Polygon) Dimensions ¶

func (p Polygon) Dimensions() int

Dimensions returns 2 because a Polygon is a 2d object.

func (Polygon) Equal ¶

func (p Polygon) Equal(polygon Polygon) bool

Equal compares two polygons. Returns true if lengths are the same and all points are Equal.

func (Polygon) GeoJSONType ¶

func (p Polygon) GeoJSONType() string

GeoJSONType returns the GeoJSON type for the object.

type Projection ¶

type Projection func(Point) Point

A Projection a function that moves a point from one space to another.

type Ring ¶

type Ring LineString

Ring represents a set of ring on the earth.

func (Ring) Bound ¶

func (r Ring) Bound() Bound

Bound returns a rect around the ring. Uses rectangular coordinates.

func (Ring) Clone ¶

func (r Ring) Clone() Ring

Clone returns a new copy of the ring.

func (Ring) Closed ¶

func (r Ring) Closed() bool

Closed will return true if the ring is a real ring. ie. 4+ points and the first and last points match. NOTE: this will not check for self-intersection.

func (Ring) Dimensions ¶

func (r Ring) Dimensions() int

Dimensions returns 2 because a Ring is a 2d object.

func (Ring) Equal ¶

func (r Ring) Equal(ring Ring) bool

Equal compares two rings. Returns true if lengths are the same and all points are Equal.

func (Ring) GeoJSONType ¶

func (r Ring) GeoJSONType() string

GeoJSONType returns the GeoJSON type for the object.

func (Ring) Orientation ¶

func (r Ring) Orientation() Orientation

Orientation returns 1 if the the ring is in couter-clockwise order, return -1 if the ring is the clockwise order and 0 if the ring is degenerate and had no area.

func (Ring) Reverse ¶

func (r Ring) Reverse()

Reverse changes the direction of the ring. This is done inplace, ie. it modifies the original data.

type Simplifier ¶

type Simplifier interface {
	Simplify(g Geometry) Geometry
	LineString(ls LineString) LineString
	MultiLineString(mls MultiLineString) MultiLineString
	Ring(r Ring) Ring
	Polygon(p Polygon) Polygon
	MultiPolygon(mp MultiPolygon) MultiPolygon
	Collection(c Collection) Collection
}

A Simplifier is something that can simplify geometry.

Source Files ¶

bound.go clone.go define.go equal.go geometry.go line_string.go multi_line_string.go multi_point.go multi_polygon.go point.go polygon.go ring.go round.go

Directories ¶

Path	Synopsis
clip	Package clip is a library for clipping geometry to a bounding box.
clip/smartclip	Package smartclip performs a more advanced clipping algorithm so it can deal with correctly oriented open rings and polygon.
encoding
encoding/ewkb
encoding/internal
encoding/mvt
encoding/mvt/vectortile
encoding/wkb	Package wkb is for decoding ESRI's Well Known Binary (WKB) format sepcification at https://en.wikipedia.org/wiki/Well-known_text_representation_of_geometry#Well-known_binary
encoding/wkt
geo	Package geo computes properties on geometries assuming they are lon/lat data.
geojson	Package geojson is a library for encoding and decoding GeoJSON into Go structs using the geometries in the orb package.
internal
maptile	Package maptile defines a Tile type and methods to work with web map projected tile data.
maptile/tilecover	Package tilecover computes the covering set of tiles for an orb.Geometry.
planar	Package planar computes properties on geometries assuming they are in 2d euclidean space.
project	Package project defines projections to and from Mercator and WGS84 along with helpers to apply them to orb geometry types.
quadtree	Package quadtree implements a quadtree using rectangular partitions.
resample	Package resample has a couple functions for resampling line geometry into more or less evenly spaces points.
simplify	Package simplify implements several reducing/simplifying functions for `orb.Geometry` types.

Version: v0.11.1 (latest)
Published: Jan 29, 2024
Platform: js/wasm
Imports: 2 packages
Last checked: 19 hours ago –

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