Function Description
Auto-split Lines function is used to split the original and new objects at intersections when drawing a line, creating multiple line objects.
- The auto-split lines object is applicable to line layers or CAD layers.
- The operation process of auto-split lines is shown in the following figure.
Draw a line object that intersects with the one in Figure 1. The comparison results between enabling the auto-split lines object and not using it are shown in Figure 2 and Figure 3.



Figure 1 Draw line feature Figure 2 Non-auto-split Figure 3 Auto-split result After the original line object (line 1 in Figure 1) is split, it is deleted. The system fields (except SmUserID) of the new line objects generated from it (lines 3 and 4 in Figure 3) are assigned by the system, while the non-system fields and the field SmUserID retain the corresponding attributes of the original line object. The attributes of the newly drawn line objects (lines 5 and 6 in Figure 3) are added to their attribute tables in the order of drawing.
- If the drawn line object intersects with a complex line object (the original object), i.e., a line object with multiple sub-objects, then with the auto-split lines object enabled, the newly drawn line object will be split at the intersection. The original object remains a complex object but will have new sub-objects generated at the intersection. You can select the object, right-click, and view it in the properties dialog.
- If the newly drawn object does not intersect with any line object, then even with the auto-split lines object enabled, no auto-split will occur, and only the drawn object will be retained.
Function Entry
- Features tab -> Objects group -> Drawing Settings drop-down menu -> Auto-split Lines.
Operation Instructions
- In the Features tab's Objects group, click the Drawing Settings drop-down button, and select the Auto-split Lines option from the drop-down menu; or use the Shift+K shortcut key to enable the auto-split lines object function. To cancel the auto-split lines object function, click the option again.
- In the current editable layer, draw a line object. After drawing, the new object and the original object are automatically split into multiple objects at the intersection.