All dimensions generated automatically are positioned in one of the (orthogonal) planes belonging the local coordinate system of a part or group.
For an object being dimensioned (part, assembly, or group) the software defines a rectangular prism circumscribed on the selected part (the prism is perpendicular to the local coordinate system of the object). Dimension lines are positioned in one of the planes of the prism, so that they do not conceal the object. In the upper left of the dialog are options that refer to these planes in which dimension lines are positioned: Distance to the first dimension line and Distance between dimension lines.
Single part or Assembly
For a single part or an assembly, the Dimensions field includes options that let you select dimensions and direction to be generated automatically.
Group
Available options:
Specify settings for color, type, and thickness of a line displaying a profile.
For groups, the Dimensions field comprises options enabling selection of dimensions and direction to be generated automatically (for total dimensions, element axes, and workframe axes).