STL (3D Printing)

STL is the veteran format of 3D printing: the model is described by triangles alone, with no color, materials or layers. That is exactly why every slicer and every printer understands it, from a home machine to an industrial one.

A map is exported to STL when the city has to be held in your hands: a model of a block, a gift with your home district, a teaching aid, a stand, a blank for an architectural presentation.

What is in the file: buildings only. Each one is extruded to its own height (the height tag, otherwise the number of floors, otherwise 9 meters — about three storeys), and pitched roofs are reconstructed from OSM tags: gabled, hipped, pyramidal, mono-pitched. Where there are no tags, the shape is chosen by the type and the size of the house. Under the model lies a solid base plate so the model stands level and prints without supports under every house.

The scale is natural, in meters: before printing, shrink the model in the slicer down to the size of your bed. The terrain itself is not part of this file — the houses stand on a plane; print the relief separately: the 3D Terrain format (terrain-mesh) delivers the Copernicus GLO-30 surface as the same kind of STL, and Elevation Model (dem-geotiff) gives the raw heights — both are linked below among the related formats. The file is binary, which is several times more compact than the text variant.