Book Image

Learning D3.js 5 Mapping - Second Edition

By : Thomas Newton, Oscar Villarreal, Lars Verspohl
Book Image

Learning D3.js 5 Mapping - Second Edition

By: Thomas Newton, Oscar Villarreal, Lars Verspohl

Overview of this book

D3.js is a visualization library used for the creation and control of dynamic and interactive graphical forms. It is a library used to manipulate HTML and SVG documents as well as the Canvas element based on data. Using D3.js, developers can create interactive maps for the web, that look and feel beautiful. This book will show you how build and design maps with D3.js and gives you great insight into projections, colors, and the most appropriate types of map. The book begins by helping you set up all the tools necessary to build visualizations and maps. Then it covers obtaining geographic data, modifying it to your specific needs, visualizing it with augmented data using D3.js. It will further show you how to draw and map with the Canvas API and how to publish your visualization. By the end of this book, you'll be creating maps like the election maps and the kind of infographics you'll find on sites like the New York Times.
Table of Contents (13 chapters)
6
Finding and Working with Geographic Data

Adding Interactivity to Your Canvas Map

In the preceding chapter, you saw one of the shining qualities of Canvas in action – animating thousands of points on the screen in a smooth animation. In this chapter, you will deal with one Canvas caveat: interaction. While interaction with HTML or SVG elements is straightforward, it requires a little more thought and some tricks to achieve with Canvas. In this chapter, you will follow along these thoughts and learn the tricks needed to do the following things:

  • Making a globe move, and adding zoom and rotation interaction to it
  • Learning how to interact with Canvas elements through picking
  • Retrieving data from a Canvas element to display it in a tooltip

After this chapter, you will have covered all important facets of Canvas, drawing, animating, and, finally, interacting with Canvas.

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