ROD objects

The Flatten command fully supports ROD objects. You can preserve ROD objects attributes, such as object name, alignments, multipart path subparts, multipart rectangle sub-rectangles, and master rectangles in multipart rectangles, by selecting the Preserve: ROD objects option on the Flatten form. When this option is disabled, ROD objects become ordinary unnamed objects, the subparts of multipart paths become ordinary paths and rectangles, the master rectangles in multipart rectangles become ordinary, unnamed rectangles, and the sub-rectangles of multipart rectangles become ordinary rectangles.

The system assigns the flattened object a name based on the hierarchical name of the ROD object by replacing slashes with dashes. For example, when you flatten the ROD object I1/I4/rect3, the resulting object is named I1-I4-rect3.

Blockages

Only instances contained within the blockage are flattened. The blockage object itself is not flattened.

• If you select an instance which is the owner of a blockage to flatten based on the flattening level, only the instance is flattened, and the blockage remains without any ownership information. If the owner instance is not selected for flattening, the ownership relation remains unchanged.
• When you flatten an instance with a placement halo, the placement halo will convert to a placement blockage with appropriate points.
• You can flatten instances containing blockages and delete the remaining blockages by using the Delete Detached blockages option on the Flatten form.

Boundaries

The Flatten command does not support PR and snap boundary objects.

• If you flatten an area boundary object which results in a non-unique name, an extension is added to the name, with a resulting message appearing in the CIW. If the associated constraint group no longer exists after the flattening operation, the object is stripped of its constraint group name, with a resulting information message appearing in the CIW. All normal transformations associated with flattening of an instance also apply to the area boundary object.
• If you flatten a cluster with a cluster boundary and the cluster boundary becomes irrelevant, the cluster object set is updated and the cluster boundary is removed. If you flatten a cluster boundary object which results in a non-unique name, an extension is added to the name, with a resulting message appearing in the CIW. It is possible to have a hierarchical set of clusters based on the depth of the Flatten command. All transformations associated with the flattening of an instance also apply to the cluster boundary object.
• If the flatten command results in a cellview that has no instances, you must remove all clusters and cluster boundary objects from the cellview.