25 lines
1.1 KiB
HTML
25 lines
1.1 KiB
HTML
---
|
|
layout: example.html
|
|
title: Measure
|
|
shortdesc: Using a draw interaction to measure lengths and areas.
|
|
docs: >
|
|
<p>The <code>getLength()</code> and <code>getArea()</code>
|
|
functions calculate spherical lengths and areas for geometries. Lengths are
|
|
calculated by assuming great circle segments between geometry coordinates.
|
|
Areas are calculated as if edges of polygons were great circle segments.</p>
|
|
<p>Note that the <code>geometry.getLength()</code> and <code>geometry.getArea()</code>
|
|
methods return measures of projected (planar) geometries. These can be very
|
|
different than on-the-ground measures in certain situations — in northern
|
|
and southern latitudes using Web Mercator for example. For better results,
|
|
use the functions in the <code>ol/sphere</code> module.</p>
|
|
tags: "draw, edit, measure, vector"
|
|
---
|
|
<div id="map" class="map"></div>
|
|
<form class="form-inline">
|
|
<label for="type">Measurement type </label>
|
|
<select id="type">
|
|
<option value="length">Length (LineString)</option>
|
|
<option value="area">Area (Polygon)</option>
|
|
</select>
|
|
</form>
|