Cleaning Objects - MapInfo_Pro - 2023

The Clean Objects command removes any self-intersections in your region data and optionally alter region data to remove overlaps and/or gaps. Clean is available whenever there are objects selected, and the table that the objects are in is editable. The Clean Objects command is located on the SPATIAL tab, in the Edit group, click Fix/Clean.

To use the Clean command:

1. Open any Map window that includes a region layer.
2. Make the region layer editable if it is not already. On the HOME tab, in the Windows group, click Tool Windows, and click Layers from the list, to open the Layers window. Click the Editable icon for the layer.
3. Select the objects that you want to clean. Ideally, all the objects in the table would be selected.
4. On the SPATIAL tab, in the Edit group, click Clean Objects from the list to open the Clean Objects dialog box.
5. Click the Enable Overlap Removal check box to remove any overlapping areas. The area of overlap will be retained in the region that has the largest area; the overlap will be removed from any other overlapping regions.
6. Click the Enable Gap Removal check box to remove any gaps between regions, where the area of the gap is less than the area provided. The area of the gap will be added to the adjacent region with the longest shared edge. Specify a maximum gap area and the area units you want to use.
7. Click OK.
   
   

   

   
   

   1 Objects before Clean operation overlap.

   2 Objects selected for Clean operation.

   3 Objects after Clean operation do not overlap.

There are several things you should be aware of when using the Clean Objects command. Although Clean Objects works on a selection of objects, it is designed to be used on an entire table at once. If Clean Objects is used on a selection, rather than on the whole table, problems can occur. For example, if not all the objects are included in the Clean Objects operation, some of the object intersections can be missed.

In addition, Clean Objects could introduce new overlaps and gaps if not all of the objects in the table are used as input. The Clean Objects operation places new nodes at the point of each intersection it encounters. The presence of these nodes can slightly change the size and shape of objects, although you would have to zoom in very closely to the site of the new nodes to notice it. These slight alterations have the potential to create small gaps and overlaps in what were previously common boundaries with other objects not included in the Clean Objects operation.

Clean Objects also removes the overlap when one object is completely inside another, however, if one object is completely inside another object, the object which is inside (often smaller than the containing object) remains, while a hole is punched in the containing object. The result does not contain any overlaps.