Friday, October 21, 2016

Video Journey Mapping

A new website allows you to to take a virtual boat journey down the Seine, a street car ride through San Francisco or a bus journey around London. Videomapia is an interactive map of videoed road, boat and train trips around the world. The map allows you to watch videos of short trips around cities and follow along with the journey on a synchronized Leaflet map.

The markers on the global Videomapia map show the locations of the uploaded videos. If you zoom in on the map you can see the individual routes taken in each video. You can then click anywhere on the journey track to start the video from that location. As the video of the trip plays out a moving marker on the map keeps track of the current location shown in the film.

Anyone can add their own videoed journeys to Videomapia. the site is entirely in Russian, so you might need to run the instructions through Google Translate.

If you like Videomapia then you might also enjoy Cyclodeo. Cyclodeo shows synchronized videoed cycling routes in cities around the world.

Cyclodeo uses Google Maps and videos of bike routes to allow users to preview routes before attempting to cycle them for themselves. The videos are synced to a Google Map of the route so that the user can click anywhere on the route and view the video at that location.

Even if you aren't a cyclist Cyclodeo allows you to virtually explore a number of global cities on video and on the accompanying maps.

Signs of Luxembourg

The University of Luxembourg wants to map the linguistic landscape of Luxembourg. They want to see how written languages are represented in public spaces and how different kinds of signs, languages and lettering help to create the linguistic landscape of a place or community.

They have therefore devised a citizen science project to help map the use of different languages in signs throughout the country. They have released an iOS and Android app which allows anyone to submit photographs of signs that they find anywhere in Luxembourg. These photographs are then plotted on the Lingscape map.

You can help contribute to this study into the diversity and dynamics of public writing by downloading the app from the Lingscape website. The project is currently centered on the languages used in signs in Luxembourg, however the app will work in any country in the world.

Thursday, October 20, 2016

How to Add 3D Buildings to a Map

Mapbox has now added an example of 3d buildings to the Mapbox GL JS documentation. The Display Buildings in 3D example map provides you with all the code you need to use extrusions to display 3d buildings in a Mapbox GL map.

One thing missing from the example map is the light properties that control the lighting of the 3D buildings: light color, intensity, position, and anchor. These light properties are easy to add to the 'Display Buildings in 3D' example map by simply adding -

map.setLight({color: "#6ef", intensity: 0.5, position: [1.15, 135, 45]});

to the map.on function.

If you want to learn more about these light properties then you might also want to have a look at the Mapbox Blog post Shading and lighting 3D features in Mapbox GL JS.

I've also created an example map of 3d buildings in Mapbox GL. In my map I've added the option to navigate the map with game-like controls. This enables you to fly around the map and 3d buildings using your forward and left & right keyboard keys. I've also used the light properties of the 3d buildings to simulate the dropping of bombs on the map. If you press your keyboard down button the building light property flashes to simulate a bomb going off on the map.

Mapping Human Colonies on Mars

Recently National Geographic has started using Leaflet.js to provide interactive versions of the beautiful supplemental posters issued with each months National Geographic magazine. The September poster, exploring life in the Pacific Ocean off British Columbia, is available to view in the British Columbia Supplement.

The October print edition of the National Geographic includes a double sided poster about Colonizing Mars. The art side of the poster depicts a possible human colony on the red planet. It explains some of the technical difficulties which would be faced in establishing a Mars colony and shows what such a colony might look like.

The map side of the poster is a new map of Mars based on imagery and data from NASA's most recent missions to the planet. If you are interested in maps of Mars you might also enjoy National Geographic's article on the history of mapping the planet, What Mars Maps Got Right (and Wrong) Through Time.

If you want to create your own interactive map from an illustration, photo or other still image then you might find Zoomable Images with Leaflet helpful. This tutorial explains how you can use GDAL2Tiles and MapTiler to render map tiles from an image. If you have a Zoomify account Showing Zoomify Images with Leaflet explains how you can create an interactive Leaflet map from your Zoomify images.

Wednesday, October 19, 2016

Redlining Maps

The Home Owners' Loan Corporation (HOLC) was a government-sponsored corporation created as part of President Franklin D. Roosevelt's New Deal. Its purpose was to refinance home mortgages, which were in default, in order to help prevent foreclosures.

The HOLC is often cited as starting the practice of mortgage redlining. Redlining is the process of denying services to residents of certain areas based on the racial composition of those areas. The term comes from the maps, created by the HOLC, which marked in red the areas where the banks would not invest. The result of these maps was that residents in the more affluent and largely white neighborhoods were far more likely to receive financing under the New Deal. Residents in the poorer and black communities were deemed more of a financial risk and so were less likely to receive financial support.

You can explore examples of redlining maps from across the United States on the Mapping Inequality website. Using the Mapping Equality map you can zoom in on locations to view HOLC maps created for a number of American cities. When you view one of the historical maps the map sidebar provides details on the local population and the percentage of the city which was redlined on the HOLC map of the city.

Tuesday, October 18, 2016

3D Buildings in the Sun

Mapbox has created another great demo showcasing the new 3d buildings feature available in Mapbox GL. This new map demonstrates how you can use shading & lighting with 3d buildings to create depth and reflect different lighting conditions.

The extrusion lighting demo map in Shading and lighting 3D features in Mapbox GL JS includes three controls. These controls allow you to change the colors of the 3d buildings, the lighting intensity and the light direction.

Using the light direction and the light intensity options you can see how you could create a map which reflects the lighting conditions during the course of a day. You can use light direction to ensure that the light on the map mirrors the light direction from the sun during different times of the day. You can then change the light intensity to reflect the rising and falling of light during sunrise and sunset.

Another great demonstration of Mapbox's 3d buildings can be seen in Robert White's Vancouver Zoning Map.

Mapping Fracking Demands on Water

Over 350 billion gallons of water are used in hydraulic fracturing in the United States. Unfortunately over half of the wells hydraulically fractured in the last five years are in areas of high or extremely high water stress, including water basins in Texas, Colorado, Oklahoma and California.

Ceres has released an interactive map to show the locations of hydraulic fracturing well locations and the related water risk trends where these wells are located. The Competition for Water in US Shale Energy Development map provides an overview of overall water stress throughout the United States. The locations of fracked wells are also shown on the map. It is therefore easy to use the map to see where hydraulic fracturing is taking place in areas of high water stress.

The map also shows the outlines of major water basins in the United States. If you click on the water basin outlines on the map you can view the total number of fracked wells using the basin for water and the percentage of wells operating in areas of high and extreme water stress. For example 99% of fracking wells using the California water basin are operating in an area of high and extreme water stress.

Mapping NATO's Global Operations

The North Atlantic Treaty Organization (NATO) was set up after World War II as an alliance of European and North American countries. Its aim was to safeguard the member countries by agreeing to a policy of mutual defense.

NATO has released a new interactive map to help explain how the organization functions and how and where it operates around the world. NATO on the Map allows you to view which countries belong to the alliance, which countries it works in partnership with and its influence on global peacekeeping.

The map allows you to view the locations of NATO's civilian headquarters, military commands and headquarters around the world. It also shows examples of where NATO has sought to "project stability in its neighbourhood and beyond." A 'Security Challenges' layer shows some of the present global threats to peace and security that NATO and its partners currently faces across the globe.

The map includes two main map views a Google Maps aerial view and a Cesium powered 3D view.

Monday, October 17, 2016

Vancouver's 3D Building Zones

Last week Mapbox revealed their new extrusion properties for data layers in Mapbox GL JS. These new extrusion properties allow you to create 3d buildings (extruding buildings by their number of floors) or other 3d data visualizations on a map using your own data layers.

Robert White has already used Mapbox's new 3d buildings option to create the impressive Vancouver Zoning Map. Robert's map not only has 3d buildings but also uses data styling to color those buildings and other map features to show Vancouver's distinct city zones.

Using the map you can explore how & where Vancouver uses zoning within the city. You can also see how this zoning has an effect on the building heights in Vancouver's neighborhoods.

If you want to see how you can create your own building height map then you might want to have a look at my How to Create a Building Height Map tutorial. Mapbox has yet to create a good tutorial for creating 3d buildings with Mapbox GL JS. However you can have a look at the demo map provided in their blog post, 3D Features in Mapbox GL JS, to see how the new extrusion properties work.

Freestyle Downhill Water Mapping

Andy Woodruff has invented a kind of hydrodynamics physics engine for interactive maps. It allows him to create an animated map which visualizes water drainage flow for any location on Earth.

In the Rain on the Terrain Andy tries to answer the question of where water would flow if you poured it over the terrain at any location on the planet. His solution is essentially to use elevation data to find the lowest adjacent location for any given location. Drop some water at this location and it will find the path of least resistance and move to the adjacent location with this lowest elevation.

Repeat this process and you can plot a long path of the least resistance, moving downhill. If you then animate a polyline along this path you can create a map of flowing rivers. Andy's map allows you to visualize the animated flow map of drainage for any location on Earth (based on his simple algorithm). The map also includes some quick links to zoom the map to a number of locations with interesting terrain.