Book Image

Mastering OpenLayers 3

By : Gábor Farkas
Book Image

Mastering OpenLayers 3

By: Gábor Farkas

Overview of this book

OpenLayers 3 allows you to create stunning web mapping and WebGIS applications. It uses modern, cutting edge browser technologies. It is written with Closure Library, enabling you to build browser-independent applications without painful debugging ceremonies, which even have some limited fallback options for older browsers. With this guide, you will be introduced to the world of advanced web mapping and WebGIS. First, you will be introduced to the advanced features and functionalities available in OpenLayers 3. Next, you will be taken through the key points of creating custom applications with OpenLayers 3. You will then learn how to create the web mapping application of yours (or your company's) dream with this open source, expense-free, yet very powerful library. We’ll also show you how to make amazing looking thematic maps and create great effects with canvas manipulation. By the end of this book, you will have a strong command of web mapping and will be well on your way to creating amazing applications using OpenLayers 3.
Table of Contents (17 chapters)
Mastering OpenLayers 3
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

Adding vector layers with a library


OpenLayers 3 offers similar capabilities out of the box. It is an interaction that combines the File API and the Drag and Drop API. As it is a completely automatic solution to add vector data from the hard drive, it needs different considerations. It is more restrictive when it comes to projection handling. We can define the projection in the constructor. If we don't, it tries to read the projection from the data itself. If it cannot find one, the interaction defaults it to the map projection.

Tip

You cannot access the interaction's default projection. If you want to change it, you have to remove the interaction from the map and construct a new one with a different projection.

Look at the file named ch03_draganddrop.js. We will extend our previous example based on its content. First, replace ch03_fileapi.js with ch03_draganddrop.js in the previous example's HTML file's head section. The only thing we have to do for this interaction to work is add it to the...