geo.spatial — factual/geo 3.0.1

Provides common interfaces for working with spatial objects and geodesics. All units are in meters/radians/steradians unless otherwise specified. Provides static spatial contexts for the earth, and some constants like the earth's radii and circumferences, along with points like the poles.

Defines protocols for unified access to Points and Shapes, to allow different geometry libraries to interoperate.

Basic utility functions for unit conversion; e.g. degrees<->radians.

Functions for computing earth radii, surface distances, and surface areas.

Constructors for shapes like bounding-boxes and circles, and utility functions over shapes for their heights, centers, areas, etc. Can also compute relationships between shapes: their intersections, contains, disjoint statuses, etc.

area clj

(area rect)

The area of a rectangle in square meters. Note that spatial4j's term 'area' actually refers to solid angle, not area; we convert by multiplying by the earth's radius at the midpoint of the rectangle.

area-in-square-degrees clj

(area-in-square-degrees rect)

The area of a rectangle in square degrees.

bounding-box clj

(bounding-box shape)

Returns the bounding box of any shape.

center clj

(center shape)

Returns the centroid of a spatial4j shape. Note that .getCenter does bad things for JTS shapes that cross the international dateline, so we use use (center (bounding-box x)) for JTS stuff.

circle clj

(circle point meters)

A spatial4j circle around the given point or lat,long, with radius in meters.

crosses-dateline? clj

(crosses-dateline? jts-geom)

degrees->radians clj

(degrees->radians degrees)

dist-at-idx clj

(dist-at-idx linestring idx)

Distance between the linestring's point at the given index and the subsequent point.

distance clj

(distance a b)

Distance between two points, in meters

distance->radians clj

(distance->radians meters)

(distance->radians meters radius)

Converts distance, in meters on the surface of the earth, to radians. Assumes earth mean radius.

distance-at-point->radians clj

(distance-at-point->radians meters point)

Converts a distance near a point on the earth into radians; using a more accurate model of the radius of the earth near that point.

distance-in-degrees clj

(distance-in-degrees a b)

Distance between two points, in degrees.

earth clj

The SpatialContext of the earth, as according to spatial4j.

earth-equatorial-circumference clj

Earth's equatorial circumference, in meters

earth-equatorial-radius clj

Earth's radius at the equator, in meters.

earth-equatorial-radius-squared clj

earth-mean-circumference clj

Earth's mean circumference, in meters.

earth-mean-radius clj

Earth's mean radius, in meters.

earth-meridional-circumference clj

Earth's circumference around a meridian, in meters.

earth-polar-radius clj

Earth's radius at the poles, in meters.

earth-polar-radius-squared clj

earth-radius clj

(earth-radius point)

Returns an approximate radius for the earth, at some point. Based on the geodetic model for an oblate spheroid.

geohash-point clj

(geohash-point point)

(geohash-point lat long)

Returns a WGS84Point used by the geohash library.

h3-point clj

(h3-point point)

(h3-point lat long)

Returns a GeoCoord used by the H3 library.

height clj

(height shape)

Returns the height of a shape, in degrees.

intersects? clj

(intersects? a b)

Do two shapes intersect in any way? Note that spatial4j's relate() considers intersection different from containment, e.g. if A completely surrounds B, their relation is not INTERSECTS. Spatial4j has a intersects() function on relations (the one used here) which considers two shapes intersecting if their intersection is non-empty; i.e. they are not disjoint.

jts-point clj

(jts-point point)

(jts-point lat long)

Returns a Point used by JTS.

length clj

(length linestring)

Get geodesic length of a (jts) linestring by summing lengths of successive points

north-pole clj

Point clj protocol

latitude clj

(latitude this)

longitude clj

(longitude this)

to-geohash-point clj

(to-geohash-point this)

to-h3-point clj

(to-h3-point this)

to-spatial4j-point clj

(to-spatial4j-point this)

point clj

point-between clj

(point-between c1 c2 dist)

radians->degrees clj

(radians->degrees radians)

radians->distance clj

(radians->distance radians)

(radians->distance radians radius)

Converts radians to meter distance on the surface of the earth. Assumes earth mean radius.

rand-point-in-radius clj

(rand-point-in-radius center-lat center-lon radius-meters)

(rand-point-in-radius center-lat center-lon radius-meters distribution)

Get a random point around the given latitude and longitude within the given radius.

(rand-point-in-radius 34.05656 -118.41881 100) (rand-point-in-radius 34.05656 -118.41881 100 :clustered) (rand-point-in-radius 34.05656 -118.41881 100 (fn [] 1))

Returns org.locationtech.spatial4j.shape.jts.JtsPoint; Use geo.spatial/latitude and geo.spatial/longitude to retrieve raw coords.

Accepts an optional 4th argument for customizing the distribution. Can be either :uniform or :clustered for built-in distributions, or a custom fn.

Distribution fn should return a float between 0.0 and 1.0 when invoked.

The built-in :clustered distribution uses a linear distribution of radius, which results in points clustered more heavily toward the center of the radius.

:uniform uses an exponential distribution of radius which results in points being spread evenly across the circle.

Default distribution is :uniform.

relate clj

(relate a b)

The relationship between two shapes. Returns a keyword:

:contains a contains b :within a falls within b :intersects a and b have at least one point in common :disjoint a and b have no points in common

resegment clj

(resegment linestring segment-length)

Repartitions a JTS LineString into multiple contiguous linestrings, each up to the provided length (in meters). Final segment may be less than the requested length. Length of individual segments may vary a bit but total length should remain the same.

Shapelike clj protocol

to-jts clj

(to-jts this)

(to-jts this srid)

Convert anything to a projected JTS Geometry.

to-shape clj

(to-shape this)

Convert anything to a Shape.

south-pole clj

spatial4j-point clj

(spatial4j-point point)

(spatial4j-point lat long)

A spatial4j point on the earth.

square clj

(square x)

square-degree-in-steradians clj

square-degrees->steradians clj

(square-degrees->steradians steradians)

steradians->area clj

(steradians->area steradians)

(steradians->area steradians radius)

Converts steradians to square meters on the surface of the earth. Assumes earth mean radius.

vincenty-distance-calculator clj

width clj

(width shape)

Returns the width of a shape, in degrees.

within-dist? clj

(within-dist? p1 p2 dist)