Each 2D domain is a rectangle at any orientation. The orientation and dimensions are defined using .tgc file commands. For the orientation it is recommended that the X-axis falls between 90° and –90° of East as it is preferable to view the 2D grid within this range and some post-processing software only operate within this range.
Several options are available for setting the grid location and orientation as a result of a number of new commands being introduced over the years. In all cases, Cell Size must be specified. The options are:
Using a four-sided polygon in a GIS layer to define the 2D grid orientation and dimensions (see Read MI Location).
Using a line (two vertices only) in a GIS layer to define the orientation of the X-axis (see Read MI Location), and Grid Size (N,M) or Grid Size (X,Y) to set the 2D grid X and Y dimensions.
Using Origin, Orientation or Orientation Angle, and Grid Size (N,M) or Grid Size (X,Y). No GIS layers are required for this option.
