The OASIS2GBR program converts OASIS or GDSII layout data into Gerber's RS274X format. It is very useful if your CAD tools create GDSII or OASIS and your mask writer accepts Gerber format.
The output Gerber units are always in units of MM no matter what the input units.
Automatically recognizes whether input file is GDSII or OASIS
The program interface is by command line
All Gerber output is using the G36/G37 area fill command
Output File Optimizations
Directly converting OASIS/GDSII to Gerber can result in extremely large Gerber files which can slow down or crash even power RIPs. Therefore Artwork has implemented two major optimizations designed to reduce both the file size and increase the speed of the Gerber RIP. These are:
Command Line Syntax
The the library is managed using the gbrxtrakapp64.exe executable. This executable takes the command line arguments and converts them into library calls the run the conversion.
gbrxtrakapp64.exe <input_oasis_file> <output_gerber_file> [OPTIONS] where <input_oasis_file> Path/filename of the OASIS or GDSII file to be translated. <output_gerber_file> Path/filename of the translated GERBER output. [OPTIONS] -layers:<list> Comma separated list of layers of interest if -layers is not present all layers will be merged -cell:<name> Set the specified cell as the view cell for extraction. if no -cell is present the program will choose the top cell automatically. -window:<minX>,<minY>,<maxX>,<maxY> Extract data from the specified window -nocompress Disable compression; default behavior is -compress which will use SR and arc recovery to minimize output file size. -mode: compact | speed Determines which compaction algorithm to use default is -mode:speed -log:<log_file> Write log to this file -silent Suppress stdout messages -overlap:overlap_in_file_units to specify amount of overlap between butting polygons. -circularize:max_chord_error parameter to control the arc recovery process. if this value=0 then arc recovery is disabled. -revalidate re-validates (post overlap) output polygons and fixes any polygon considered to be illegal. -format:XY Specify the number of integer and decimal places for co-ordinate data along both X,Y axes. X is the number of integer digits and Y is the number of decimal digits.
Command Line Examples
Create data for all layers using the default top cell from an OASIS/GDSII file
gbrxtrakapp64.exe sample_input.gds sample_output.gbr
This will produce a RS274X file for each layer in the layout database since the -layer command line option was not used.
Faster conversion as oppose to compact output file
gbrxtrakapp64.exe sample_input.gds sample_output.gbr -mode:speed
This option checks the input file for hierarchy. If sufficient hierarchy is found, it uses an alternate algorithm and emphasizes speed over compaction. If sufficient hierarchy is not found, it uses the the original algorithm for superior compaction. -mode:compact uses the original algorithm and emphasizes compaction over speed.
Create Gerber files for all layers on a specific cell (TEST) from an OASIS/GDSII file
gbrxtrakapp64.exe sample_input.gds sample_output.gbr -cell:TEST
Create Gerber files for specific set of layers (1,2:2,3) from an OASIS/GDSII file
gbrxtrakapp64.exe sample_input.gds sample_output.gbr -layers:1,2:2,3
the -layers: argument enables the user to specify a list of layers or layers:datatype to output.
Turn off the repetition recognition algorithms
gbrxtrakapp64.exe sample_input.gds sample_output.gbr -nocompress
Writing a log file to disk
gbrxtrakapp64.exe sample_input.gds sample_output.gbr -log:sample.log
Suppressing messages to stdout
gbrxtrakapp64.exe sample_input.gds sample_output.gbr -silent
By default, OASIS2GBR will open a window and display progress messages. To suppress this behavior use the command line option: -silent.
If you wish to run the conversion from a script or batch it is useful to know that the program returns one of two return codes:
0 success 1 failure Information about the cause of error is sent to stderr
Gerber Output Specification
The Gerber output format is the same no matter what the input units and resolution are.
Format: of 3.5
Geometry - How Holes/Islands are Handled
The default behavior is to create holes and islands using "cut lines" often referred to as keyhole geometry. This page describes in detail what the output geometries look like and discusses possible options if the current approach causes problems for the mask writer.
Platform and Operating System
64 bit Windows 7/8/10
64 bit RHEL 5 or higher