Select the EDIT tab and then the Coordinates tab to allow a user-defined coordinate frame to be specified that can be used for measurements and exported. There are a range of options that can be used individually or combined. Note that Dot3D follows the common convention that the red axis is X; the green axis is Y and the blue axis is Z.
To set the X Y and Z axis and origin select “Set” under User Defined.
Pick Origin can set the position of the origin at a point in the scene.
Select Pick Origin to set a 0,0,0 point. Hold the point and it will give you a zoom window so you can select your exact point. Long press the point to set it as the new origin.
To align the coordinate system with a plane in the scene, first select the axis you wish to be perpendicular to the plane (default Z). Click Primary and select a point in the scene on the plain of interest. This will force the selected axis to be perpendicular to the selected plane.
To add a secondary constraint, select the axis and click Secondary and select a second point in the scene. Click the up or down arrows for the direction you want your axis.
Select Confirm to save the Origin and Axes.