Straight Construction Line Based on Graphic Line

1. Call the Line command.

2. Move the cursor over a straight graphic line, using object snappings, and press or <Enter>. Two connected 2D nodes will be created at endpoints of the selected line, and the new construction line will pass through such nodes. Since the arbitrarily angled lines creation mode is active by default, the resulting line will be selected as parent object for creating a parallel line.

Then you can either continue the creation of the parallel line, cancel the selection and switch the mode, or exit the command.

Moreover, the same technique can be used for creating straight construction lines based on graphic lines in the Circle command, as well as in the connected drawing mode of the 2D Node and Graphic Line commands.