next up previous contents index
Next: The Current Transform Button: Up: The Edit Button: Edit Previous: Opening New Cells -   Contents   Index

Object Tests

While a file is being read, tests for reentrant or otherwise strange polygons are normally performed. A polygon that is reentrant overlaps itself. This can be a problem since the polygon may be rendered differently on different CAD systems, as the presentation of the polygon may become ambiguous. The test is performed on physical data only. This adds a little overhead. The test is skipped if the boolean variable NoPolyCheck is set (with the !set command). This test can also be turned off from the Conversion - Import panel.

If when reading a file a warning message about ``badly formed polygons'' appears in the log file, here is how to proceed. Note the cell that contained the polygon, and edit it. Use the !polycheck command to select the bad polygons. The Info command in the View Menu can be used to obtain the vertex list. In many cases, the polygon will not cause problems, however it is wise to recreate one that is flagged as bad. The Create Cell command can be used to save the bad polygons to a separate cell for further inspection.

Xic checks for identical, coincident objects when reading input files, and prints a warning message in the log file if such objects are found. This test can be turned off by setting the NoCheckCoinc variable, or from the Conversion - Import panel. If the Merge boxes ... button in the Conversion - Import panel is set, duplicate objects (not subcells) will be deleted and no warning is issued. In addition, box objects will be clipped and/or merged so that no two boxes on the same layer overlap.


next up previous contents index
Next: The Current Transform Button: Up: The Edit Button: Edit Previous: Opening New Cells -   Contents   Index
Stephen R. Whiteley 2006-10-23