Some Boolean commands will automatically update entities after the Boolean operation is performed on attached lower-order entities. For instance, if you use an AADD Boolean operation to add several areas together that are attached to a single volume, that volume will be updated by replacing the original areas with the newly produced area. This releases you from the work of deleting the higher-order entity (volume in this case) and rebuilding it with bottom up techniques. The following commands perform automatic updating of higher-order entities:
Updating can occur only if the Boolean operation produces entities that are equal to the original entity. For instance, if an ASBA operation cuts an area into two pieces, the two new pieces will replace the original area, and the underlying volume will be updated to include the new areas. However, if the ASBA operation cuts a piece out of the original area (to create a hole for instance), no entities can be updated.
Figure 5.60: Automatic Boolean Updating With AFILLT shows an example of automatic Boolean updating. In this example, a fillet area (AFILLT) is placed between two intersecting volumes. The Boolean fillet operation creates the fillet area, but also automatically updates the areas on the surfaces of the volumes, and the volumes are updated to replace the two original surface areas with the four new surface areas.
