OBJ (3D Printing)

OBJ (3D Printing) is a specialized exporter which exports OBJ files that are geared towards 3D printing rather than GIS based workflows. This streamlines options for scaling the print to a manageable arbitrary size scaled for printing/CNC with additional solid bottom and sidewall options.

The OBJ file format is a simple data-format that represents 3D geometry alone — namely, the position of each vertex, the UV position of each texture coordinate vertex, vertex normals, and the faces that make each polygon defined as a list of vertices, and texture vertices.

OBJ files may contain texture and material references. The texture may be stored in an external image file (usually *.jpg or *.png) and the material may be defined in a *.MTL file.

OBJ coordinates have no units specified within the format. As with other loaded data, Global Mapper will recognize and use external projection files (like *.prj) that are stored in the same directory with the same filename at the *.OBJ file.

 

Import

For more information on loading OBJ files see Working with 3D Models

OBJ files are stored in a right-handed system.

 

Export

To export an OBJ file, select File > Export > Export 3D Format... then choose OBJ (3D Printing). The layer may also be exported directly by right clicking on the layer in the Control Center and choosing Export in the Layer sub-menu.

This OBJ export option is designed to create small-scale 3D model outputs. This export method is focused on print dimensions and options necessary for a model used in 3D printing.

Model Output Dimensions

  • Choose the direct X and Y print dimensions or measurements for the data, ideally scaled to fit on the bed of a 3D printer. 3D print dimensions are typically scaled to millimeter, centimeters, or inches (specify the unit below).

  • Preserve Horizontal Aspect Ratio: Check this box to maintain the X and Y ratio to prevent horizontal distortion.

  • Units: Only applies to horizontal (X&Y) values.

  • Z Scalar: Vertical Exaggeration. Increase this value for more dramatic elevation changes equally across the dataset. The result is similar to the 3D viewer’s vertical exaggeration option.

Add base and walls extended below lowest elevation: Enable this option to generate a base and sidewalls for the model.

  • Base Thickness (mm): This determines how far below the lowest point in the data the base will be extruded to. Setting this to 0 will create the base at the lowest point. This may create a hole or thin area in your 3D print depending on layer thickness.

Add base to walls: Uncheck this box to only create walls with no base.

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.

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.

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.