EGS Archive Files

The EGS Archive format is an ASCII text format that represents multiple hierarchical designs. EGS Archive files include information such as drawing shapes, layout units, database precision, grid spacing and, optionally, a layers definition including layer colors, numbers, and names. They do not contain information about the connectivity of a layout design.

Originating from a former Hewlett-Packard product called the Engineering Graphics System (EGS), the EGS Archive format is useful as an intermediate file for transferring input/output to various third-party translators. It is also the best format for translating graphic shapes into the Series IV and MDS products. In addition, the EGS Archive format is easy to parse and read, so if you have created your own software tools, this is a very useful format for transferring graphics shapes into these tools.

When importing an EGS Archive file into Advanced Design System, you may specify a Layers File Name for the creation of a layers definition file (the Layers File Name field is located in the Import dialog box). This file will be automatically created and will contain the layer information from the EGS Archive file, as well as layers automatically added as necessary during import. All designs created during import reference this layers file.

Oval or hatch shapes of the EGS Archive format are not supported in Advanced Design System.

Importing EGS Archive Files

The procedure for importing each format is generally the same, however the available options differ. For a step-by-step tutorial on importing a layout file, refer to Importing a Layout. For specific import options related to importing EGS Archive Files, refer to Import EGS Archive Options. For information on mapping EGS Archive files to ADS, refer to Mapping EGS Archive to ADS.

Import EGS Archive Options

File > Import > EGS Archive Format > More Options

Other than layer characteristics, there are no definable options available for importing files in the EGS Archive format.

The Define Layers button invokes the Layer Editor. For Layer Editor options, see Defining Layers.

Note ADS does not support the character `$' in layer names. Translation will fail if the import file contains this character in the layer names.

Mapping EGS Archive to ADS

The table below shows the mapping of EGS Archive file shapes to Advanced Design System layout shapes.

EGS Archive Object	Advanced Design System Layout Equivalent
Line with width = 0	Polyline
Line with width > 0	Path
Polygon with width = 0	Polygon
Polygon with width > 0	Polygon with cutline on longest segment
Rectangle with width = 0	Rectangle
Rectangle with width > 0	Polygon with cutline on longest segment
Circle with width = 0	Circle
Circle with width > 0	Polygon with cutline to the right
Arc with width = 0	Polyline
Arc with width > 0	Polygon

Exporting EGS Archive Files

The procedure for exporting each format is generally the same, however the available options differ. For a step-by-step tutorial on exporting a layout file, refer to Exporting a Layout. For specific export options related to exporting EGS Archive Files, refer to Export EGS Archive Options. For information on mapping ADS to EGS Archive files, refer to Mapping ADS to EGS Archive.

Export EGS Archive Options

File > Export > EGS Archive Format > More Options

Include Mask Layers

When this option is selected, a list of mask layers is included with the translated design. This option is selected as the default.

Paths As Polygons

When Paths As Polygons is selected, the design paths or traces are exported as polygons. This should be selected for the following conditions:

• Paths or traces have mitered or curved corners that need to be preserved in the translation.
• The EGS Archive file has paths with endpoint types other than flush that need to be preserved in the program database.

This option is deselected as the default.

Holes As Polygons

When this is selected, holes are converted to polygons. When Holes As Polygons is not selected (this is the default), polygons with holes are translated as single-segment polygons, the false edge segment becoming part of the polygon. Some systems may not be able to tolerate this type of complex polygon. For these systems, select Holes As Polygons .
This option is deselected as the default.

Flatten Components

When Flatten Components is selected, all instances whose artwork type is defined with an AEL macro will be flattened when exported. For example, if a design contains an MLIN it will be flattened. This option is deselected as the default. It only affects the current design and will not change the hierarchy.

All Filled

When this is selected, all data is transferred as filled. This option is deselected as the default.

Flatten All

When Flatten All is selected, all levels of hierarchy are automatically removed and a single flat design is exported. There are no references from the top-level structure to any other structure in the design. This option is useful when your post-processor does not support or correctly translate hierarchy in EGS Archive files. Please note: if a substructure was instanced more than once, selecting this option can substantially increase the size of the file.
This option is deselected as the default.

Auto Merge

When Auto Merge is selected, all shapes for every mask layer that intersect or overlap are merged. This option is deselected as the default.

Layers To Exclude

Layers can be excluded from the EGS Archive export by entering the layer IDs. Multiple IDs can be entered using space or comma delimiter.

Define Layers

The Define Layers button invokes the Layer Editor. For Layer Editor options, see Defining Layers.

Mapping ADS to EGS Archive

The table below represents the mapping Advanced Design System layout shapes to EGS Archive file shapes.

Advanced Design System Layout Object	EGS Archive Equivalent
Polyline	Line
Path with PathsAsPolygons	Polygon
Path without PathsAsPolygons	Line
Circle	Circle
Rectangle	Rectangle
Polygon	Polygon
Wire	Line