Feature Description

In editable state, updates parts of line or polygon objects with a drawn polyline. The Local Update function uses intersecting segments between the drawn polyline and source object (target line object) to form new objects.

• Applies to line layers, polygon layers, and CAD layers.
• When target objects are unselected, start/end points of drawn polylines must lie on object boundaries. Enable snapping during operation.
• For selected target objects, Clip Mode can be used. Drawn polylines require at least two intersection points with target objects.
• Applicable to simple objects or individual sub-objects of complex objects, but not compounds.
• Update results vary by object type. Details for line/polygon updates:
  • Unselected Line Objects (Capture Mode)

    Illustrates Local Update for unselected non-closed line objects.

    Figure 1 shows target line object. Update with polyline in Figure 2 (start/end points must lie on object). Bold highlighted segments in Figure 2 show update result.

    Update polyline divides original object into three segments. After setting start/end points, press Ctrl/Shift to toggle results (bold segments in Figure 3).

    Figure 1: Object to Be Updated	Figure 2: Local Update Operation	Figure 3: Toggled Update Result

  • Selected Line Objects (Clip Mode)

    Illustrates Local Update for selected non-closed line objects.

    Figure 4 shows target line object. Update with polyline in Figure 5 (requires ≥2 intersections). Bold segments in Figure 5 show update result.

    Update polyline divides original object into three segments. Press Ctrl/Shift to toggle results (bold segments in Figure 6).

    Figure 4: Object to Be Updated	Figure 5: Local Update Operation	Figure 6: Toggled Update Result

  • Unselected Polygon Objects (Capture Mode)

    Illustrates Local Update for unselected closed polygon.

    Ensure start/end points lie on polygon boundary. Blue area previews update result (Figure 8), with bold highlighted boundary. Press Ctrl/Shift to toggle results (blue area between bold segments in Figure 9).

    Figure 7: Closed Polygon to Be Updated	Figure 8: Update Result 1	Figure 9: Update Result 2

  • Selected Objects (Clip Mode)

    Illustrates Local Update for selected closed polygon.

    Start/end points can be inside/outside polygon boundary, but drawn polyline must have ≥2 intersections. Blue area previews update result (Figure 11). Press Ctrl/Shift to toggle results (Figure 12).

    Figure 10: Closed Polygon to Be Updated	Figure 11: Update Result 1	Figure 12: Update Result 2

Feature Entry

• Features Tab->Feature Editing Group Dropdown->Local Update.

Steps

1. Set layer to editable state in Layer Manager.
2. Click Local Update in Features Tab->Feature Editing Group. Cursor changes to polyline .
3. Two modes available:
   • Capture Mode: Move cursor to target object boundary. Start/end points must lie on boundary. If not, prompt appears: "The point should be on the line when updating with Capture Mode. Please select an object if you want to update with Clip Mode." Restart drawing.
     Note:

     Enable Point Snapping to Lines in Snapping Settings for Capture Mode.

   • Clip Mode: Select target object first. Drawn polyline requires ≥2 intersections with object boundary.
4. Continue drawing. When points snap to object boundary, updated shape highlights. Current polyline divides boundary into segments. Hold Ctrl to toggle selection.
5. Right-click to confirm update, completing Local Update operation.