The GeoScene3D 3D Grid File Format (.grd3) is used for three dimensional grids. Each node in the grid represents one floating point or integer value. All values in each grid are of the same type.

In contrast to 2D grids that normally contains elevation data the nodes in a 3D grid represents a value that may originate from an interpolated XYZ points or may have been set when editing the 3D grid manually. The grid layers are stacked from bottom up.

The file format is binary and will not be documented in detail.