Add Lines
Functionality: Add auxiliary lines that allow objects to snap to them and move along their direction, ensuring the precise and neat arrangement of objects.
Steps
1.Click the Add Lines 
button in the Vector Editing toolbar. Use the left mouse button to click two points and draw an auxiliary line in any direction. See the illustration below:
Draw Auxiliary Lines
Note: While moving and arranging vectors using auxiliary lines, you can set the snap buffer distance for objects to be snapped to the lines and onsider the Z value (elevation) when calculating the buffer distance. See the illustration below:
Set Snap Buffer Value