Here at Pointr, we use GeoJSON (short for Geographic JavaScript Object Notation) data across our mapping solutions to record a wide variety of mapping structures. In this article, we’ll take a deep dive into GeoJSON to gain a clear understanding of its origins, its history, and its development into the mapping standard it has become today.
Pointr Maps use GeoJSON data format for storing indoor mapping data, including sites, buildings, levels, and a wide range of map content such as points of interest (POIs), furniture arrangements, and even the layout of walls.
We’ll explore:
- What is GeoJSON?
- GeoJSON origins.
- What makes GeoJSON today’s mapping standard?
- How Pointr uses GeoJSON?
- How Pointr categorizes indoor maps
- Design objectives and common challenges
What is GeoJSON?
GeoJSON is a format for encoding (and representing) a variety of different geographic data structures.
GeoJSON is specifically designed for the exchange and storage of geographic data, allowing developers to easily share, integrate, and manipulate spatial information in a variety of mapping applications. It’s a comprehensive format that is human-readable, lightweight, and based on the JavaScript Object Notation (JSON) syntax, making it highly versatile and widely supported.
It’s an open standard, and features include points (therefore addresses and locations), line strings (therefore streets, highways, and boundaries), polygons (countries, provinces, tracts of land), and multi-part collections of these types. Most mapping products either support or are compatible with GeoJSON data.
An example showing what a GeoJSON file looks like.
GeoJSON origins
In the early 2000s, JSON (JavaScript Object Notation) gained popularity as a lightweight and readable data format used for structured data representation in JavaScript. As JSON usage expanded, the need for a standardized geospatial format arose due to the increasing demand for interoperability and the rise of web mapping applications.
To address this need, JSON was extended to include geospatial capabilities, allowing for the representation and exchange of geographic information. The Open Geospatial Consortium's introduction of the Web Feature Service (WFS) specification further emphasized the need for a format to transfer geospatial features between clients and servers efficiently.
In 2008, the GeoJSON specification was officially introduced as a standardized geospatial format based on JSON.
What makes GeoJSON today’s mapping standard?
GeoJSON has emerged as today's mapping standard due to its versatility, simplicity, and wide support within the mapping community. It offers a range of benefits that have made it the format of choice for representing geospatial data in various mapping applications.
Here are some of the aspects of GeoJSON that have helped it become the de facto mapping standard for many mapping applications:
- Compatibility - GeoJSON can seamlessly integrate with web-based mapping platforms thanks to its compatibility with JavaScript and JSON syntax. This allows developers to easily parse, manipulate, and visualize geographic data using common tools and libraries.
- Simplicity - GeoJSON's straightforward structure and human readability make it accessible to both developers and non-technical users. Its simplicity enables easy data exchange and manipulation across different applications and systems.
- Lightweight - GeoJSON's compact size and efficient encoding make it ideal for transmitting geographic data over networks, which results in better performance and reduced bandwidth requirements. The lightweight nature of GeoJSON is particularly important for web mapping applications that deal with large datasets or require real-time updates.
- Support community - GeoJSON's extensive support within the mapping community has played an important role in its emergence as today's mapping standard. Major mapping libraries and frameworks, including Leaflet, OpenLayers, and Mapbox, have integrated GeoJSON support into their APIs, making it easier for developers to work with GeoJSON and providing developers with reliable tools for parsing, rendering, and interacting with geospatial data.
- Standardization & interoperability - GeoJSON's open standardization and interoperability foster collaboration, feedback, and improvement from a diverse community of users and developers. It provides a common language for representing geospatial data, enabling seamless integration of datasets from diverse sources and platforms, and has evolved to meet the changing needs and advancements in mapping technologies - ensuring its continued relevance and applicability.
How does Pointr use GeoJSON?
Pointr uses the GeoJSON data format for storing indoor mapping data, including sites, buildings, floorplan outlines, point of interest, furniture, and other building structure in each building. However, there’s no set standard for indoor maps.
On the other hand, outdoor maps (cities, highways, terrain, etc.) have an approximate standard followed by leading outdoor map products such as Google Maps and Apple Maps, while indoor mapping doesn’t have an industry-established standard. Most providers use an arbitrary, proprietary convention such as Apple’s IMDF.
.png?width=600&height=340&name=coordinate-geojson%20(1).png) |
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| In Pointr Cloud, POIs are in GeoJSON format, compatible with standard outdoor map formats such as Google Maps and Apple Maps. |
An example of how GeoJSON works with Google Maps. Source: Google Maps Platform |
How does Pointr categorize indoor maps?
At Pointr, we categorize indoor maps as follows:
- Site(s): Large areas encompass indoor and outdoor spaces, such as hospital campuses, workplace campuses, shopping malls, and airport sites.
- Building(s): Indoor areas with multiple levels and facilities. Each building is associated with a specific site, including offices, parking lots, sky bridges, tunnels, and more.
- Level(s): Where the digital maps are located. Each level contains map content like POIs, Map Objects, Wayfinding Networks, Geofences, and IoT Devices. All content within a level is associated with a particular building.
A visual showcases of the relationships among sites, buildings, and levels within Pointr Maps.
Our platform enables an experience across a whole site, from crossing the campus boundaries to entering the parking lot and going to a meeting room in a building. However, we do not offer mapping outside of a site, which is typically already provided by prominent players, including Google Maps, Apple Maps, Open Street Maps, and others.
In order to define appearance, map layers, and metadata, we use a style.json configuration file which is required by various map rendering libraries, including Maplibre and Mapbox. This style.json file contains
- The visual appearance of the map.
- Map layers (including their source, relevant attributes, and applicable expressions).
- General metadata (e.g., version, name) and more.
Design objectives and common challenges
In creating our GeoJSON specifications for indoor maps, we aim to adhere closely to existing standards used for outdoor maps. This ensures that a large user base across numerous buildings can seamlessly utilize our maps. We prioritize flexibility to accommodate various use cases without sacrificing the integrity of the data format, all while maintaining the scalability of our maps.
The table below outlines the specific challenges we address while developing our GeoJSON specifications for indoor maps.
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Pointr Solutions |
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Consistency with existing standards for smooth indoor-outdoor transition In large sites such as airports or workplace campuses, the ability to guide users seamlessly between indoor and outdoor areas is crucial for a seamless wayfinding experience. |
Precise and seamless indoor-outdoor wayfinding When developing our GeoJSON specification, we prioritize aligning with existing outdoor map standards. This ensures that Pointr Maps facilitate effortless transitions between indoor and outdoor spaces, maintaining a consistent wayfinding experience. |
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Dynamic building toggling Large sites often have multiple buildings, and the desired display may vary depending on the application. Sometimes, highlighting and centering on a single building is preferred, while in other cases, showing multiple buildings simultaneously is more desirable. |
Flexible building viewing options Pointr Maps allows users to focus on a single building or view multiple buildings simultaneously based on their needs. For instance, users can navigate from one floor in one building to another floor in a different building using a bridge between the buildings. |
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Persistent feature highlighting Users anticipate that when they highlight a feature, such as an ATM point of interest, it will remain visible and highlighted even when they zoom in or out. |
Feature visibility in complex map rendering Pointr Maps address the challenge of maintaining feature visibility in situations involving clashes and zoom levels during map rendering. We prioritize flexibility, accommodating diverse use cases without compromising data format while ensuring the scalability of our maps.
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Support for different zoom levels Maps should support different zoom levels to accommodate users' varying needs. For instance, when zooming out, users may see a section of a building, such as a parking lot, but when zooming in, the map should provide more relevant and detailed information, like specific parking spots, to enhance usability and usefulness. |
Optimized display at different zoom-levels Pointr's indoor maps adjust their presentation to show users the most relevant information at each zoom level. For instance, when zooming out, you may see building sections such as "Check out," "Parking Lot C," or "Border Control"), but as you zoom in, these sections may disappear to reveal finer details like checkout tills, parking spots, or border control desks. |
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Avoid undesired clashing Multiple map objects can converge at the exact location, leading to confusion and difficulty in understanding. For example, on a supermarket map, multiple racks of products may be adjacent. When zoomed out, if not handled properly, this will likely lead to a confusing experience, showing lots of objects on top of each other, making them difficult to read and understand. |
Prioritizing visibility and enhancing readability Our design addresses this issue by effectively managing object clashes. We prioritize the visibility of important items while allowing less significant ones to disappear, reducing visual clutter and enhancing readability.
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Summing up
GeoJSON is an open standard with interoperability that encourages collaboration, feedback, and improvement from its diverse community of users and developers.
It provides a common language for representing geospatial data, enabling the seamless integration of datasets from different sources and platforms, and it has evolved to meet the changing needs and advancements in mapping technologies.
Most mapping products either support or are compatible with GeoJSON data. At Pointr, we use GeoJSON to define specifications for indoor maps and overcome the challenges associated with delivering a market-leading mapping experience to our many users worldwide.
