When going beyond modifying existing examples you might be looking for a way to setup your own code with dependency management together with external dependencies like OpenLayers 3.
This tutorial serves as a suggested project setup using NPM and Browserify for the most basic needs. There are several other options and in particular you might be interested in compiling your own code together with OpenLayers 3.
Create a new empty directory for your project and navigate to it by running
mkdir new-project && cd new-project. Initialize your project using npm init
and answer the questions asked.
At this point you can ask NPM to add required dependencies by running
npm install --save-dev openlayers browserify watchify uglify-js. Watchify and
Uglify will be used to monitor for changes and to build into a minified
bundle.
Place your application code in index.js. Here is a simple starting point:
OpenLayers 3var ol = require('openlayers');
var map = new ol.Map({
target: 'map',
layers: [
new ol.layer.Tile({
source: new ol.source.OSM()
})
],
view: new ol.View({
center: [0, 0],
zoom: 0
})
});You will also need an ìndex.html file that will use your bundle. Here is a simple
example:
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>Using Browserify with OpenLayers</title>
<link rel="stylesheet" href="node_modules/openlayers/dist/ol.css" type="text/css">
<style>
#map {
width: 400px;
height: 250px;
}
</style>
</head>
<body>
<div id="map"></div>
<script src="bundle.js"></script>
</body>
</html>With simple scripts you can introduce the commands npm run build and npm start to
manually build your bundle and watch for changes, respectively. Add the following
to the script section in package.json:
"scripts": {
"start": "watchify index.js --outfile bundle.js",
"build": "browserify index.js | uglifyjs --compress --output bundle.js"
}Note that bundle.js will contain your application code and all dependencies
used in your application, in this case the official full build of OpenLayers 3.
If you only need parts of OpenLayers 3 you can create
custom builds.