By Kevin Duffin
Geovis Project Assignment @RyersonGeo SA 8905 Fall 2018
Creating a custom web mapping application can seem like a daunting task for an individual without a whole lot of technical experience. These individuals, myself included, can feel as though they must first learn computer science before they are able to perform web mapping. However, there are a variety of web services which allow for the creation of powerful geovizualization application without the detailed knowledge of computer programming.
One such service is ESRI’s Web Appbuilder for ArcGIS.
Web Appbuilder is an application hosted on ArcGIS online which allows users to add functionality to custom web maps. An exciting feature of the Web Appbuilder is the ability to create maps not only in 2D, but also in 3D via the scene view in Web Appbuilder.
The scene view environment allows users to create a variety of 3D interactive mapping applications on a virtual globe. Navigation around the virtual world is incorporated, and various customization are possible via a variety of out of the box functionalities which can be easily incorporated to any application.
Pretty great right? Follow along and learn how to make a 3D web app!
Introduction to my data
The economies of many nations around the world, including Canada, rely very heavily on natural resource use. In recent times there has been a push by many countries to decouple their economies from natural resource use to both increase the sustainability of their economy, and to decrease their environmental impact.
Material footprint is a measure of domestic material use developed by Wiedmann, T. O., Schandl, H., Lenzen, M., Moran, D., Suh, S., West, J., and Kanemoto, K in 2015. The material footprint(MF) of a nation is the total amount global raw materials extraction that can directly attributed to the final demand of that nations economy.
When developing the metric, Weidmann et al determined the MF per capita of every nation in the world. The group also calculated the MF per capita for various material types, such as biomass materials, construction materials, fossil fuels, and metal ores. I joined Weidmann et al.’s MF data to a country shapefile using ArcMap and the resulting shapefile was exported and saved to my local computer. This is the data I used to create my geovisualization project.
The goal of my project was to create a web mapping application which allows the user to view the MF data on a virtual globe, and toggle between material types. By viewing which material types are important to various nations, the user can then make inferences about sustainability of those nations.
Getting Started: Publishing Layers to ArcGIS Online
In order to create the web application, I first needed to publish the spatial data to ArcGIS Online. To do this I first logged in to my ArcGIS online account. If you do not have an ArcGIS Online account, you can create a free personal account or sign up through your organization, such as university or business. Once signed in, navigate to the “My Content” tab and click the “Add Item” button. For my project I added the MF data from my computer. If your data is saved on your local computer, ensure that it is in ZIP format. I added the MF layer six times, as I had six layers I wanted to display on my application. I named one layer the Material Footprint, four layers using the material groups, and one representing the select few countries which did not have data.
Creating the Map
Once the layers were uploaded, I navigated to the “Create” button and hit “map”. This opened a map viewer tab where I was able to create the basemap for my application on a 2D surface. I added the six layers to the map viewer and began making the basemap. The “change style” tab was used to classify and select a colour scheme for each layer. I then configured pop- ups to display the MF value of a nation when a country is selected. Once I was happy with all the layers, I then saved the layers and the map, and navigated back to “My Content”.
Creating the Web Scene
I next needed to display the layers I just created in a 3D environment. From the “Create Tab”, I selected “Create Scene”. A scene viewer page opened and the virtual 3D globe which I used to display my layers was generated. Using the “Modify Scene” tab, I added my six layers that I formatted in the map view from my content. As this scene will become the base of the mapping application, it is important that I configured all the desired setting in the scene view, as these settings will not be able to be changed in the application itself. For example, I altered the order of the layers in my legend, chose a basemap, specified the suns position in the sky, and optimized the performance of the scene in scene settings by ensuring the 3D graphics slide bar was set to Performance rather than quality. I then saved the scene and navigated back to “My Content”.
Creating the Web App
In the “Create” tab, I then created an App using the Web Appbuilder. In the following “Create a web app” pop up, I specified 3D and gave the app a title, a tag, and a brief summary.
I then needed to specify to Scene which I wanted to use as the baselayer for my app. I navigated to the Scene I just created through the “Choose web scene” button in the scene setting window. This then projected my 3D MF layers onto the virtual globe into the map. I then navigated to the theme window and chose a graphic theme for my application.
Functionality is added to Web Appbuilder applications through widgets. Widgets are tools that can be added to the application. These tools perform a variety of functions. Also, the number of widgets you can incorporate into an app is based on the theme you have selected, so choose wisely. In my application I chose four main widgets, Legend, About, Layer List and 3D Extrusion. The legend widget simply adds a legend to the app which updates depending on the layer being displayed. I configured the About widget to display text introducing the application. The layer List is the widget which enables the toggling between MF layers. Fnally, the 3D widget allows for several different 3D functionalities. I selected the “Area Extrusion” visualization type to extrude the countries based on their Material Footprint per Capita Values. Along with the 3D extrusion, a display bar is added the app which displays the MF values of each nation. By clicking on a nation name in the display bar, the view automatically zooms to that country. Neat!
After all the functionality was added to the application, I added a few finishing touches. A proper summary and description were added to the Web App page, and a simple splash widget was added to introduce the application.
Try it out here!
Try the application out here, and thanks for following along!