@turf/area - npm Package Compare versions

Comparing version 4.7.3 to 5.0.4

index.d.ts

@@ -1,11 +0,8 @@
-/// <reference types="geojson" />
+import { AllGeoJSON } from '@turf/helpers'
 
-type Feature = GeoJSON.Feature<any>;
-type Features = GeoJSON.FeatureCollection<any>;
-
 /**
  * http://turfjs.org/docs/#area
  */
-declare function area(features: Feature | Features): number;
-declare namespace area { }
-export = area;
+export default function area(
+    geojson: AllGeoJSON
+): number;

index.js

@@ -1,3 +0,2 @@
-var area = require('@mapbox/geojson-area').geometry;
-var geomReduce = require('@turf/meta').geomReduce;
+import { geomReduce } from '@turf/meta';
 
@@ -8,3 +7,3 @@ /**
  * @name area
- * @param {FeatureCollection|Feature<any>} geojson input GeoJSON feature(s)
+ * @param {GeoJSON} geojson input GeoJSON feature(s)
  * @returns {number} area in square meters
@@ -20,6 +19,108 @@ * @example
  */
-module.exports = function (geojson) {
-    return geomReduce(geojson, function (value, geometry) {
-        return value + area(geometry);
+function area(geojson) {
+    return geomReduce(geojson, function (value, geom) {
+        return value + calculateArea(geom);
     }, 0);
-};
+}
+
+var RADIUS = 6378137;
+// var FLATTENING_DENOM = 298.257223563;
+// var FLATTENING = 1 / FLATTENING_DENOM;
+// var POLAR_RADIUS = RADIUS * (1 - FLATTENING);
+
+/**
+ * Calculate Area
+ *
+ * @private
+ * @param {GeoJSON} geojson GeoJSON
+ * @returns {number} area
+ */
+function calculateArea(geojson) {
+    var area = 0, i;
+    switch (geojson.type) {
+    case 'Polygon':
+        return polygonArea(geojson.coordinates);
+    case 'MultiPolygon':
+        for (i = 0; i < geojson.coordinates.length; i++) {
+            area += polygonArea(geojson.coordinates[i]);
+        }
+        return area;
+    case 'Point':
+    case 'MultiPoint':
+    case 'LineString':
+    case 'MultiLineString':
+        return 0;
+    case 'GeometryCollection':
+        for (i = 0; i < geojson.geometries.length; i++) {
+            area += calculateArea(geojson.geometries[i]);
+        }
+        return area;
+    }
+}
+
+function polygonArea(coords) {
+    var area = 0;
+    if (coords && coords.length > 0) {
+        area += Math.abs(ringArea(coords[0]));
+        for (var i = 1; i < coords.length; i++) {
+            area -= Math.abs(ringArea(coords[i]));
+        }
+    }
+    return area;
+}
+
+/**
+ * @private
+ * Calculate the approximate area of the polygon were it projected onto the earth.
+ * Note that this area will be positive if ring is oriented clockwise, otherwise it will be negative.
+ *
+ * Reference:
+ * Robert. G. Chamberlain and William H. Duquette, "Some Algorithms for Polygons on a Sphere", JPL Publication 07-03, Jet Propulsion
+ * Laboratory, Pasadena, CA, June 2007 http://trs-new.jpl.nasa.gov/dspace/handle/2014/40409
+ *
+ * @param {Array<Array<number>>} coords Ring Coordinates
+ * @returns {number} The approximate signed geodesic area of the polygon in square meters.
+ */
+function ringArea(coords) {
+    var p1;
+    var p2;
+    var p3;
+    var lowerIndex;
+    var middleIndex;
+    var upperIndex;
+    var i;
+    var area = 0;
+    var coordsLength = coords.length;
+
+    if (coordsLength > 2) {
+        for (i = 0; i < coordsLength; i++) {
+            if (i === coordsLength - 2) { // i = N-2
+                lowerIndex = coordsLength - 2;
+                middleIndex = coordsLength - 1;
+                upperIndex = 0;
+            } else if (i === coordsLength - 1) { // i = N-1
+                lowerIndex = coordsLength - 1;
+                middleIndex = 0;
+                upperIndex = 1;
+            } else { // i = 0 to N-3
+                lowerIndex = i;
+                middleIndex = i + 1;
+                upperIndex = i + 2;
+            }
+            p1 = coords[lowerIndex];
+            p2 = coords[middleIndex];
+            p3 = coords[upperIndex];
+            area += (rad(p3[0]) - rad(p1[0])) * Math.sin(rad(p2[1]));
+        }
+
+        area = area * RADIUS * RADIUS / 2;
+    }
+
+    return area;
+}
+
+function rad(_) {
+    return _ * Math.PI / 180;
+}
+
+export default area;

package.json

 {
   "name": "@turf/area",
-  "version": "4.7.3",
+  "version": "5.0.4",
   "description": "turf area module",
-  "main": "index.js",
+  "main": "main",
+  "module": "index",
+  "jsnext:main": "index",
   "types": "index.d.ts",
   "files": [
     "index.js",
-    "index.d.ts"
+    "index.d.ts",
+    "main.js"
   ],
   "scripts": {
-    "test": "node test.js",
-    "bench": "node bench.js"
+    "pretest": "rollup -c ../../rollup.config.js",
+    "test": "node -r @std/esm test.js",
+    "bench": "node -r @std/esm bench.js"
   },
+  "repository": {
+    "type": "git",
+    "url": "git://github.com/Turfjs/turf.git"
+  },
   "keywords": [
@@ -23,20 +31,22 @@ "turf",
   "license": "MIT",
-  "repository": {
-    "type": "git",
-    "url": "git://github.com/Turfjs/turf.git"
-  },
-  "homepage": "https://github.com/Turfjs/turf",
   "bugs": {
     "url": "https://github.com/Turfjs/turf/issues"
   },
+  "homepage": "https://github.com/Turfjs/turf",
   "devDependencies": {
-    "benchmark": "^2.1.4",
-    "load-json-file": "^2.0.0",
-    "tape": "^4.6.3",
-    "write-json-file": "^2.0.0"
+    "@std/esm": "*",
+    "benchmark": "*",
+    "load-json-file": "*",
+    "rollup": "*",
+    "tape": "*",
+    "write-json-file": "*"
   },
   "dependencies": {
-    "@mapbox/geojson-area": "^0.2.2",
-    "@turf/meta": "^4.7.3"
+    "@turf/helpers": "^5.0.4",
+    "@turf/meta": "^5.0.4"
+  },
+  "@std/esm": {
+    "esm": "js",
+    "cjs": true
   }
 }

README.md

 # @turf/area
 
-# area
+<!-- Generated by documentation.js. Update this documentation by updating the source code. -->
 
+## area
+
 Takes one or more features and returns their area in square meters.
@@ -9,3 +11,3 @@
 
--   `geojson` **([FeatureCollection](http://geojson.org/geojson-spec.html#feature-collection-objects) \| [Feature](http://geojson.org/geojson-spec.html#feature-objects)&lt;any>)** input GeoJSON feature(s)
+-   `geojson` **[GeoJSON](http://geojson.org/geojson-spec.html#geojson-objects)** input GeoJSON feature(s)
 
@@ -12,0 +14,0 @@ **Examples**

New alerts

Major refactor

Supply chain risk

Package has recently undergone a major refactor. It may be unstable or indicate significant internal changes. Use caution when updating to versions that include significant changes.

Found 1 instance in 1 package

Improved metrics

Total package byte prevSize

10512

increased by152.21%

Number of package files

6

increased by20%

Lines of code

237

increased by664.52%

Number of lines in readme file

51

increased by4.08%

Worsened metrics

Dev dependency count

6

increased by50%

Number of medium supply chain risk alerts

1

increased byInfinity%

Dependency changes

• + Added@turf/helpers@^5.0.4

• + Added@turf/helpers@5.1.5(transitive)

• + Added@turf/meta@5.2.0(transitive)

• - Removed@mapbox/geojson-area@^0.2.2

• - Removed@mapbox/geojson-area@0.2.2(transitive)

• - Removed@turf/meta@4.7.4(transitive)

• - Removedwgs84@0.0.0(transitive)

• Updated@turf/meta@^5.0.4