STL files are 3D model formats commonly used in CAD and 3D Printing applications. STL files describe only the surface geometry of a three dimensional object without any representation of color, texture or other common 3D Model attributes.


For more information on loading STL files see Working with 3D Models. STL files typically use a Y-up orientation.


There are 3 options for exporting STL files: 

Elevation Data Export

The Export STL command allows the user to export any loaded elevation grid data sets to a STL format file.

To export loaded elevation data to an STL format, go to File > Export > Export Elevation Grid Format..., or right click on the layer in the Overlay Control Center and choose export from the Layer sub-menu.

When selected, the STL (ASCII Text or Binary) File (Elevation Data Only) command displays the STL Export Options dialog which allows the user to setup the export. The dialog consists of a General options panel which allows the user to set up the grid spacing and vertical units, a Tiling Panel, a Coordinate Offset/Scale tab and an Export Bounds tab which allows the user to set up the portion of the loaded data they wish to export.

Elevation data may be exported from a raster grid format to other 3D model formats by first exporting to this STL option.

Interpolate to Fill Small Gaps in Data

Any small areas with missing data will be filled in by interpolating the surrounding valid data. This is useful for filling small gaps between adjacent tiles or small holes in elevation data.

Generate PRJ File

When selected, a *.PRJ file describing the projection of the coordinates in the file will automatically be created in the same folder, and sharing the filename of the export.

Export a Binary STL File (Much Smaller than Text STL)

The default export is an ASCII text readable STL format. Check this option to export the file as binary, which will reduce the file size.

Extrude edges of file to a base elevation

This setting is typically used for 3D printing applications. This will create a base layer to the mesh, at the specified extrusion base elevation. Specify a base elevation at the desired absolute elevation value, at which to stop the sides of the model.

Add a base to the generated mesh

This will create a flat base for the model, and the absolute elevation value specified in the extrusion base elevation. This setting may be combined with the extrude edges setting above, for 3D printing of solid or hollow models, with a flat bottom.

Export to a Z-up Orientation

STL files use Y for the vertical axis designation by convention (Y-Up orientation). Check this option to use Z for the vertical axis.

Vector Data Export

Existing 3D models may be exported to STL files as well.

STL Files typically use a Y-Up orientation.

3D File Export Options

Specify the axis orientation to use in the export. Global Mapper labels the vertical axis as Z, but in some 3D formats the vertical axis is designed as the Y-axis. Check the Export model as Y-up option to use the Y-up axis orientation.

Export Bounds

3D Mesh features do not support cropping within mesh objects. With a specified export bounds, mesh features inside the export bounds will be exported, uncropped. Mesh features with no part inside the export bound will not be included in the export.

For more information on the bounds specification options see Export Bounds.

Format Updates

Below is a summary of recent changes to STL format support:

18.2 Reduced memory usage when exporting large TIN datasets to STL
17.2 Added support for double-precision coordinates for the 3D model formats (OBJ, DAE, PLY, STL). This allows models that use large coordinate values (like UTM) to maintain precision when loaded into Global Mapper.
17.1 Added ability for user to specify that a base be added to the generated STL mesh when exporting DEM. A new script option, “ADD_BASE” is also provided for the export script command.
17.0 [Scripting] Added support for extruding the edges of the generated mesh when exporting elevation data to STL format when using the EXPORT_ELEVATION command. Just add EXTRUDE_EDGES=YES to the command to enable extrusions, and optionally, add, for example, BASE_ELEVATION=50 to extrude to an elevation of 50 (the default is 0). When extrusion is enabled, any grid rectangle that has a corner that's invalid (i.e., is not present in the gridded data) or below the base elevation setting is excluded from the export. These options are also supported in the UI when exporting elevation data to STL.
17.0 [Scripting] Added scripting control for exporting 3D models in “Z-up” and “Y-up” orientations. When using the EXPORT_ELEVATION command to export elevation data to STL format, which exports to Y-up orientation by default, add Z_UP=YES to export to Z-up orientation instead. Conversely, when using the EXPORT-VECTOR command to export vector features to 3D model formats like OBJ, STL, DAE, etc. (but not SketchUp), add Y_UP=YES to the command to cause it to export to Y-up orientation instead. In addition, you can add NO_PROMPTING=YES to the EXPORT_VECTOR command to prevent the 3D export options dialog from popping up during your script.
16.2 Added support for loading and exporting STL.