Guide Lines are horizontal, vertical, or slanted lines that can be placed anywhere in the Work Area panel to aid in object placement and nodes alignment.
To create a new guide line, position cursor on either horizontal (1) or vertical (2) ruler, depress the primary mouse button and drag cursor to the work area.
New guide lines are created by dragging them from rulers of the Work Area.
Snap nodes to guidelines option is accessible via main menu (node editing mode) > Edit > Nodes > Snap
Snap objects to guidelines option is accessible via main menu (select / transform mode) > Options > Snap Objects
Guide lines can be used for objects splitting. Place the guide line on the object. Select object and then select the guide line. Click secondary mouse button on the guide line to access pop-up menu. Choose Slice Selected Objects command.
If you need to cut object with curved shape, please read Split Objects with Mask chapter.
Use main menu > Options > Guide Lines to lock or erase guide lines or to switch on/off snapping of objects to the guide lines.