• garycollins24

This Beautiful World Blog 5 | Blending Maps to Background Colour | Protecting Our Global Heritage

Welcome to blog number 5 in my "This Beautiful World" series, where I am sharing my learnings during lockdown to grow my skills in mapping in Mapbox, and using these visualisations in Tableau. In the other blogs I have covered how subtle changes in colour can make your maps POP!, how to visualise a road on a map via from coordinates from Google Maps and how to create long shadows in Mapbox maps to bring extra depth and feel. In this blog I am going to cover how to blend maps into background colours, as I have done with my viz 'Protecting our Global Heritage'.


The Thinking Behind the Viz

My thinking behind this viz was that I wanted to grow my skills in integrating a map into a viz in a much more seamless way than I had done previously. As an example, I was happy with my #IronQuest Grand Canyon Map overall, however I couldn’t help but think the map looked like it was 'just stuck onto the page', it was just ‘there’, it didn’t blend in as well as I had hoped:

The purpose of this next viz was to experiment with using both maps and colours better to create an overall feel. I don’t come from a design background, and design doesn’t really come naturally to me, so this was a good opportunity to get some more practice in!


Building the Viz

I found an interesting dataset on the World Heritage Sites, giving lots of data about reach site. I had an idea to create a dark styled map with highlighted data points, and then a long multi layered Sankey to give a sense of each of the dimensions. Key for me on this viz was to get a map to blend in far better to its surroundings and background to the viz than I had done previously. I didn’t want to create another viz where the map looked like it was just put onto the viz – it needed to be seamless.

The basic technique that I used in this viz was to create a Mapbox map of the world, and for the land masses I brought the colouring right down on the colour opacity to 25, which made the countries more ‘see though’. Once I then brought this map into Tableau and applied a colour background to the map, the land masses blended in really well to this background colour.

I am going to assume that you have read my previous blogs on how to create maps in Mapbox, so won't be covering that now. If you haven't, please check out these previous blogs where I cover off some of the basics about Mapbox, and also integrating Mapbox with Tableau.

So, walking this though from the creation of a Map in Mapbox, firstly I created a map with the following layers:

Water, using colour #005160 and opacity at 100

Hillshade, using colour # 292924 and opacity at 100

Mapbox-terrain-rgb using colour #233c7b and opacity at 100

Ne-10m-admin-0-countries-2-0y17ro using colour #000000 and opacity at 25 (note: I obtained this layer from https://www.naturalearthdata.com where you can get a variety of additional layers that can be uploaded to Mapbox. This particular layer shows each country.)

The opacity on the country layer here is the key element. As you will see, this enables a background colour in Tableau to come through the countries on the map.

This is what the map looked like in Mapbox:

Now over into Tableau, I brought the Mapbox map in as a background to the data set of the World Heritage sites, without a background colour at first and it looked like this:

I then matched the background colour of the view in Tableau with the same colour as used in Mapbox for the Water layer.

To do this, right click on the white space around the map, click on ‘Format’, then onto ‘Worksheet Colour’, then ‘More Colours’, select to Colour Sliders and enter the hex colour number the same as the Water colour in Mapbox (in this case # 005261).

Once the background colour for the Map in Tableau is the same as the water colour in Mapbox, it darkened off the colour of the countries nicely and kept the colours in keeping with the background.

Here they images are, side by side, on the left without a background colour in Tableau, and on the right with a background colour:

I was really pleased with this result, giving the map a much more natural feel that it belonged on the viz, rather than just being 'there'.

Colour Variations

Once I had created this effect with blending the Map into the background colour, I spent some time experimenting with different colour backgrounds, I ended up with the green blue, as it felt more appropriate for the subject content.


I hope this blog has been useful. Join me for blog 6 in this series where I will walk though my learning journey in LIDAR data, used to produce a visualisation of Salisbury Cathedral, famous for being the highest Spire in England:

Keep on vizzing!