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

Creating Images from Simple Text

In this chapter, a high-level overview of Scalable Vector Graphics (SVG) will be presented by explaining how it operates and what elements it encompasses. In a browser context, SVG is very similar to HTML and is one of the means by which D3 expresses its power. Understanding the nodes and attributes of SVG will empower us to create many kinds of visualizations, not just maps. This chapter includes the following points:

  • A general overview of SVG and its key elements
  • The SVG coordinate system
  • The primary elements of SVG (lines, rectangles, circles, polygons, and paths)

SVG, an XML markup language, is designed to describe two-dimensional vector graphics. The SVG markup language resides in the DOM as a node that describes exactly how to draw a shape (a curve, line, circle, or polygon). Just like HTML, SVG tags can also be styled from standard CSS...