Prototype Fund OSM-3D-Terrain roadmap

OSM-3D-Terrain, a project participating in the 2026 Prototype Fund round, aims to produce 3D scenes from OSM and terrain data.

The OpenStreetMap database does not include terrain elevation data, which makes it necessary to use additional data sources to produce 3D scenes that incorporate terrain. Luckily, such data is increasingly available under open licenses. While OSM2World can already use SRTM elevation data, this dataset has long been superseded in resolution by other open data sources. And thanks to projects working on aggregating multiple datasets, such as Mapterhorn, it has become easier than ever to achieve global coverage while still using high-quality local sources where they are available.

Making good use of this data nevertheless requires some work. Some steps are relatively straighforward:

• Support at least some of the common data formats for elevation data, such as XYZ tiles, HGT, GeoTIFF oder LAS/LAZ.
• Identify good data sources under suitable licenses. Ensure a working mechanism to propagate attribution and meet other legal requirements.
• Implement the ability to output the resulting scenes as 3D tiles.

However, the main challenge is to properly integrate OSM-based 3D models with the terrain data. Interpolation between sites with known elevation is the obvious starting point, but merely generating terrain through interpolation and placing models on top of that terrain produces low-quality and visibly implausible results. Instead, knowledge from OSM data must be used to further tweak and refine the terrain. Elements to consider include:

• Vertical structures such as bridges and tunnels, and objects attached to them
• Assumptions about the flatness or incline of water bodies, roads, railways and other features
• Explicit attributes such as numerical inclines and the direction of steps
• Building entrances and level information
• Cliffs, retaining walls and other discontinuities in smooth terrain

To be useful in practice, the approaches developed to integrate terrain data with OSM data need to fit certain constraints. For example, large 3D worlds are often subdivided into tiles to meet performance requirements – both during delivery and during the initial content generation steps. This makes it essential that tweaks to the terrain do not lead to discontinuities at tile boundaries. Also, real-time rendering requires suitable level of detail mechanisms to ensure acceptable performance when rendering distant terrain.

The goal is to offer this new functionality through the existing OSM2World library interface. Because some data which would be helpful with terrain integration is currently not available in OSM, it may also be useful to suggest improvements to OpenStreetMap tagging standards as part of this project.

The Prototype Fund supports innovative free and open source software with funds from the German Federal Ministry of Research, Technology and Space.

SWS-JG2: 3D-Terrain in OpenStreetMap-Welten (OSM-3D-Terrain)

Förderkennzeichen 16IS26S01