Helpful tools for creating maps in D3
Drawing maps requires a combination of knowledge and good understanding of GIS, GeoJSON, Projections, and so on as well as techniques and skills for creating the maps. In this section, we will look at a few selected tools that facilitate the generation of interactive maps with D3.
Color scales
As we discussed in the first section, the colors and color scales that the author chooses can have a huge impact for the reader to perceive the visualization. Therefore, I want to show how we can efficiently create color scales in D3.
Scales can map a certain domain of values to a range of different values using interpolation. We usually use this to create scales for axes. Axes, however, map a domain of values onto a pixel range. In our case, we want to use these scales on colors to map a value domain to a color range. We can achieve this using these color interpolation functions:
d3.interpolateRgb: RGB and HEX values, such as#00FF00d3.interpolateHsl: HSL values...
