@turf/isolines - npm Package Compare versions

Comparing version 4.4.0 to 4.5.1

index.d.ts

@@ -1,11 +0,14 @@
-/// <reference types="geojson" />
+import {Points, MultiLineStrings} from '@turf/helpers'
 
-type Points = GeoJSON.FeatureCollection<GeoJSON.Point>;
-type LineStrings = GeoJSON.FeatureCollection<GeoJSON.LineString>;
-
 /**
  * http://turfjs.org/docs/#isolines
  */
-declare function isolines(points: Points, z: string, resolution: number, breaks: Array<number>): LineStrings;
+declare function isolines(
+    points: Points,
+    breaks: number[],
+    zProperty?:string,
+    propertiesToAllIsolines?: Object,
+    propertiesPerIsoline?: Object[]): MultiLineStrings;
+
 declare namespace isolines { }
 export = isolines;

index.js

@@ -1,15 +0,11 @@
-//https://github.com/jasondavies/conrec.js
-//http://stackoverflow.com/questions/263305/drawing-a-topographical-map
-var tin = require('@turf/tin');
 var bbox = require('@turf/bbox');
-var grid = require('@turf/point-grid');
-var inside = require('@turf/inside');
-var square = require('@turf/square');
+var meta = require('@turf/meta');
 var helpers = require('@turf/helpers');
-var distance = require('@turf/distance');
-var planepoint = require('@turf/planepoint');
-var featurecollection = helpers.featureCollection;
-var linestring = helpers.lineString;
-var point = helpers.point;
-var Conrec = require('./conrec');
+var invariant = require('@turf/invariant');
+var gridToMatrix = require('grid-to-matrix');
+var marchingsquares = require('marchingsquares');
+var multiLineString = helpers.multiLineString;
+var coordEach = meta.coordEach;
+var collectionOf = invariant.collectionOf;
+var featureCollection = helpers.featureCollection;
 
@@ -22,9 +18,10 @@ /**
  * @param {FeatureCollection<Point>} points input points
- * @param {string} z the property name in `points` from which z-values will be pulled
- * @param {number} resolution resolution of the underlying grid
- * @param {Array<number>} breaks where to draw contours
- * @returns {FeatureCollection<LineString>} isolines
+ * @param {Array<number>} breaks values of `zProperty` where to draw isolines
+ * @param {string} [zProperty='elevation'] the property name in `points` from which z-values will be pulled
+ * @param {Object} [propertiesToAllIsolines={}] GeoJSON properties passed to ALL isolines
+ * @param {Array<Object>} [propertiesPerIsoline=[]] GeoJSON properties passed, in order, to the correspondent
+ * isoline; the breaks array will define the order in which the isolines are created
+ * @returns {FeatureCollection<MultiLineString>} a FeatureCollection of {@link MultiLineString} features representing isolines
  * @example
- * // create random points with random
- * // z-values in their properties
+ * // create random points with random z-values in their properties
  * var points = turf.random('point', 100, {
@@ -37,66 +34,111 @@ *   bbox: [0, 30, 20, 50]
  * var breaks = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
- * var isolined = turf.isolines(points, 'z', 15, breaks);
- * //=isolined
+ * var isolines = turf.isolines(points, breaks, 'temperature');
+ *
+ * //addToMap
+ * var addToMap = [isolines];
  */
-module.exports = function (points, z, resolution, breaks) {
-    var tinResult = tin(points, z);
-    var bboxBBox = bbox(points);
-    var squareBBox = square(bboxBBox);
-    var sizeCellGrid = distance(point([squareBBox[0], squareBBox[1]]), point([squareBBox[2], squareBBox[1]]), 'kilometers') / resolution;
-    var gridResult = grid(squareBBox, sizeCellGrid, 'kilometers');
-    var data = [];
+module.exports = function (points, breaks, zProperty, propertiesToAllIsolines, propertiesPerIsoline) {
+    // Default Params
+    zProperty = zProperty || 'elevation';
+    propertiesToAllIsolines = propertiesToAllIsolines || {};
+    propertiesPerIsoline = propertiesPerIsoline || [];
 
-    for (var i = 0; i < gridResult.features.length; i++) {
-        var pt = gridResult.features[i];
-        for (var j = 0; j < tinResult.features.length; j++) {
-            var triangle = tinResult.features[j];
-            if (inside(pt, triangle)) {
-                pt.properties = {};
-                pt.properties[z] = planepoint(pt, triangle);
-            }
-        }
-    }
+    // Input validation
+    collectionOf(points, 'Point', 'Input must contain Points');
+    if (!breaks) throw new Error('breaks is required');
+    if (!Array.isArray(breaks)) throw new Error('breaks must be an Array');
+    if (!isObject(propertiesToAllIsolines)) throw new Error('propertiesToAllIsolines must be an Object');
+    if (!Array.isArray(propertiesPerIsoline)) throw new Error('propertiesPerIsoline must be an Array');
+    if (typeof zProperty !== 'string') throw new Error('zProperty must be a string');
 
-    var depth = Math.sqrt(gridResult.features.length);
-    for (var x = 0; x < depth; x++) {
-        var xGroup = gridResult.features.slice(x * depth, (x + 1) * depth);
-        var xFlat = [];
+    // Isolined methods
+    var matrix = gridToMatrix(points, zProperty, true);
+    var isolines = createIsoLines(matrix, breaks, zProperty, propertiesToAllIsolines, propertiesPerIsoline);
+    var scaledIsolines = rescaleIsolines(isolines, matrix, points);
 
-        for (var g = 0; g < xGroup.length; g++) {
-            if (xGroup[g].properties) {
-                xFlat.push(xGroup[g].properties[z]);
-            } else {
-                xFlat.push(0);
-            }
-        }
-        data.push(xFlat);
+    return featureCollection(scaledIsolines);
+};
+
+/**
+ * Creates the isolines lines (featuresCollection of MultiLineString features) from the 2D data grid
+ *
+ * Marchingsquares process the grid data as a 3D representation of a function on a 2D plane, therefore it
+ * assumes the points (x-y coordinates) are one 'unit' distance. The result of the isolines function needs to be
+ * rescaled, with turfjs, to the original area and proportions on the map
+ *
+ * @private
+ * @param {Array<Array<number>>} matrix Grid Data
+ * @param {Array<number>} breaks Breaks
+ * @param {string} zProperty name of the z-values property
+ * @param {Object} [propertiesToAllIsolines={}] GeoJSON properties passed to ALL isolines
+ * @param {Object} [propertiesPerIsoline=[]] GeoJSON properties passed to the correspondent isoline
+ * @returns {Array<MultiLineString>} isolines
+ */
+function createIsoLines(matrix, breaks, zProperty, propertiesToAllIsolines, propertiesPerIsoline) {
+    var isolines = [];
+    for (var i = 1; i < breaks.length; i++) {
+        var threshold = +breaks[i]; // make sure it's a number
+
+        var properties = Object.assign(
+            {},
+            propertiesToAllIsolines,
+            propertiesPerIsoline[i]
+        );
+        properties[zProperty] = threshold;
+        var isoline = multiLineString(marchingsquares.isoContours(matrix, threshold), properties);
+
+        isolines.push(isoline);
     }
-    var interval = (squareBBox[2] - squareBBox[0]) / depth;
-    var xCoordinates = [];
-    var yCoordinates = [];
-    for (var d = 0; d < depth; d++) {
-        xCoordinates.push(d * interval + squareBBox[0]);
-        yCoordinates.push(d * interval + squareBBox[1]);
-    }
+    return isolines;
+}
 
-    var c = new Conrec();
-    c.contour(data, 0, resolution, 0, resolution, xCoordinates, yCoordinates, breaks.length, breaks);
-    var contourList = c.contourList();
+/**
+ * Translates and scales isolines
+ *
+ * @private
+ * @param {Array<MultiLineString>} isolines to be rescaled
+ * @param {Array<Array<number>>} matrix Grid Data
+ * @param {Object} points Points by Latitude
+ * @returns {Array<MultiLineString>} isolines
+ */
+function rescaleIsolines(isolines, matrix, points) {
 
-    var fc = featurecollection([]);
-    contourList.forEach(function (c) {
-        if (c.length > 2) {
-            var polyCoordinates = [];
-            c.forEach(function (coord) {
-                polyCoordinates.push([coord.x, coord.y]);
-            });
-            var poly = linestring(polyCoordinates);
-            poly.properties = {};
-            poly.properties[z] = c.level;
+    // get dimensions (on the map) of the original grid
+    var gridBbox = bbox(points); // [ minX, minY, maxX, maxY ]
+    var originalWidth = gridBbox[2] - gridBbox[0];
+    var originalHeigth = gridBbox[3] - gridBbox[1];
 
-            fc.features.push(poly);
-        }
+    // get origin, which is the first point of the last row on the rectangular data on the map
+    var x0 = gridBbox[0];
+    var y0 = gridBbox[1];
+
+    // get number of cells per side
+    var matrixWidth = matrix[0].length - 1;
+    var matrixHeight = matrix.length - 1;
+
+    // calculate the scaling factor between matrix and rectangular grid on the map
+    var scaleX = originalWidth / matrixWidth;
+    var scaleY = originalHeigth / matrixHeight;
+
+    var resize = function (point) {
+        point[0] = point[0] * scaleX + x0;
+        point[1] = point[1] * scaleY + y0;
+    };
+
+    // resize and shift each point/line of the isolines
+    isolines.forEach(function (isoline) {
+        coordEach(isoline, resize);
     });
+    return isolines;
+}
 
-    return fc;
-};
+/**
+ * Checks input type
+ *
+ * @private
+ * @param {*} input to be checked
+ * @returns {boolean} true if the input is an Object
+ */
+function isObject(input) {
+    return (!!input) && (input.constructor === Object);
+}

package.json

 {
   "name": "@turf/isolines",
-  "version": "4.4.0",
+  "version": "4.5.1",
   "description": "turf isolines module",
@@ -9,4 +9,3 @@ "main": "index.js",
     "index.js",
-    "index.d.ts",
-    "conrec.js"
+    "index.d.ts"
   ],
@@ -30,2 +29,5 @@ "scripts": {
   "author": "Turf Authors",
+  "contributors": [
+    "Stefano Borghi <@stebogit>"
+  ],
   "license": "MIT",
@@ -37,15 +39,19 @@ "bugs": {
   "devDependencies": {
+    "@turf/envelope": "^4.5.1",
+    "@turf/point-grid": "^3.14.0",
+    "@turf/random": "^3.13.0",
     "benchmark": "^2.1.4",
-    "tape": "^4.6.3"
+    "load-json-file": "^2.0.0",
+    "matrix-to-grid": "3.0.0",
+    "tape": "^4.6.3",
+    "write-json-file": "^2.0.0"
   },
   "dependencies": {
-    "@turf/bbox": "^4.4.0",
-    "@turf/distance": "^4.4.0",
-    "@turf/helpers": "^4.4.0",
-    "@turf/inside": "^4.4.0",
-    "@turf/planepoint": "^4.4.0",
-    "@turf/point-grid": "^4.4.0",
-    "@turf/square": "^4.4.0",
-    "@turf/tin": "^4.4.0"
+    "@turf/bbox": "^4.5.1",
+    "@turf/helpers": "^4.5.1",
+    "@turf/invariant": "^4.5.1",
+    "@turf/meta": "^4.5.1",
+    "grid-to-matrix": "^1.2.0",
+    "marchingsquares": "^1.2.0"
   }
 }

README.md

@@ -11,5 +11,7 @@ # @turf/isolines
 -   `points` **[FeatureCollection](http://geojson.org/geojson-spec.html#feature-collection-objects)<[Point](http://geojson.org/geojson-spec.html#point)>** input points
--   `z` **[string](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String)** the property name in `points` from which z-values will be pulled
--   `resolution` **[number](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number)** resolution of the underlying grid
--   `breaks` **[Array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array)<[number](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number)>** where to draw contours
+-   `breaks` **[Array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array)<[number](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number)>** values of `zProperty` where to draw isolines
+-   `zProperty` **\[[string](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String)]** the property name in `points` from which z-values will be pulled (optional, default `'elevation'`)
+-   `propertiesToAllIsolines` **\[[Object](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object)]** GeoJSON properties passed to ALL isolines (optional, default `{}`)
+-   `propertiesPerIsoline` **\[[Array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array)<[Object](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object)>]** GeoJSON properties passed, in order, to the correspondent
+    isoline; the breaks array will define the order in which the isolines are created (optional, default `[]`)
 
@@ -19,4 +21,3 @@ **Examples**
 ```javascript
-// create random points with random
-// z-values in their properties
+// create random points with random z-values in their properties
 var points = turf.random('point', 100, {
@@ -29,7 +30,9 @@ bbox: [0, 30, 20, 50]
 var breaks = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
-var isolined = turf.isolines(points, 'z', 15, breaks);
-//=isolined
+var isolines = turf.isolines(points, breaks, 'temperature');
+
+//addToMap
+var addToMap = [isolines];
 ```
 
-Returns **[FeatureCollection](http://geojson.org/geojson-spec.html#feature-collection-objects)<[LineString](http://geojson.org/geojson-spec.html#linestring)>** isolines
+Returns **[FeatureCollection](http://geojson.org/geojson-spec.html#feature-collection-objects)<[MultiLineString](http://geojson.org/geojson-spec.html#multilinestring)>** a FeatureCollection of [MultiLineString](http://geojson.org/geojson-spec.html#multilinestring) features representing isolines
 
@@ -36,0 +39,0 @@ <!-- This file is automatically generated. Please don't edit it directly:

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

Dependency count

6

decreased by-25%

Number of lines in readme file

60

increased by5.26%

Worsened metrics

Total package byte prevSize

11094

decreased by-60.29%

Dev dependency count

8

increased by300%

Number of package files

5

decreased by-16.67%

Lines of code

139

decreased by-76.16%

Number of medium supply chain risk alerts

1

increased byInfinity%

Dependency changes

• + Added@turf/invariant@^4.5.1

• + Added@turf/meta@^4.5.1

• + Addedgrid-to-matrix@^1.2.0

• + Addedmarchingsquares@^1.2.0

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

• + Added@turf/invariant@5.2.0(transitive)

• + Added@turf/meta@5.2.0(transitive)

• + Addedgrid-to-matrix@1.4.0(transitive)

• + Addedmarchingsquares@1.3.3(transitive)

• - Removed@turf/distance@^4.4.0

• - Removed@turf/inside@^4.4.0

• - Removed@turf/planepoint@^4.4.0

• - Removed@turf/point-grid@^4.4.0

• - Removed@turf/square@^4.4.0

• - Removed@turf/tin@^4.4.0

• - Removed@turf/distance@4.7.3(transitive)

• - Removed@turf/inside@4.7.3(transitive)

• - Removed@turf/planepoint@4.7.3(transitive)

• - Removed@turf/point-grid@4.7.3(transitive)

• - Removed@turf/square@4.7.3(transitive)

• - Removed@turf/tin@4.7.3(transitive)

• Updated@turf/bbox@^4.5.1

• Updated@turf/helpers@^4.5.1