Book Image

OpenLayers 3: Beginner's Guide

By : Thomas Gratier, Paul Spencer, Erik Hazzard
Book Image

OpenLayers 3: Beginner's Guide

By: Thomas Gratier, Paul Spencer, Erik Hazzard

Overview of this book

<p>This book is a practical, hands-on guide that provides you with all the information you need to get started with mapping using the OpenLayers 3 library.</p> <p>The book starts off by showing you how to create a simple map. Through the course of the book, we will review each component needed to make a map in OpenLayers 3, and you will end up with a full-fledged web map application. You will learn the key role of each OpenLayers 3 component in making a map, and important mapping principles such as projections and layers. You will create your own data files and connect to backend servers for mapping. A key part of this book will also be dedicated to building a mapping application for mobile devices and its specific components.</p>
Table of Contents (22 chapters)
OpenLayers 3 Beginner's Guide
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Time For action – applying Zoomify sample knowledge to a single raw image


There are some quite important differences to make an equivalent map version of the Zoomify sample. Let's see how:

  1. Copy the sample from the Zoomify example previously created into the usual sandbox directory.

  2. Change the URL to /assets/data/1797-map-of-Dublin.jpg.

  3. Set the imgCenter variable to [imgWidth / 2, imgHeight / 2];.

  4. Remove the line code, var crossOrigin = 'anonymous';.

  5. Replace the ol.layer.Tile with ol.layer.Image.

  6. Then, change the source variable with the following code:

    var source = new ol.source.ImageStatic({
      attributions: [
      new ol.Attribution({
        html: '&copy; <a href="https://commons.wikimedia.org/wiki/File:1797-map-of-Dublin.jpg#Summary">Wikipedia Commons</a>'
      })
      ],
      url: url,
      imageSize: [imgWidth, imgHeight],
      projection: proj,
      imageExtent: proj.getExtent()
    });
  7. Open your browser and you will see the same image you already got from the Zoomify sample, but you will get a less smooth...