GDSPY README

Gdspy is a Python module for creating GDSII stream files, usually CAD layouts. It includes a layout viewer for the geometries created, and it can also be used to import and merge GDSII files.

Note:

As of version 0.5, gdspy is NOT backwards compatible with older versions. The main incompatibility is that the layer argument in all applicable classes and functions has been moved to a position just before datatype in the argument list. LayoutViewer has also been extensively improved. See the history of changes for all compatibility changes.

Installation

Requirements:

• Python (tested with versions 2.7 and 3.4)
• Numpy
• C compiler if you are building it from source

Installation from source is as simple as:

python setup.py install

Gdspy can also be installed with pip:

pip install gdspy

Windows users will need a development environment to compile the boolean extension module (automatically performed by the install command above).

Pre-compiled Windows binaries are also offered for 32 and 64-bit systems and should be preferable for most users: download here.

Usage

The file gdspy-sample.py is a sample script to show the features provided by this module. The complete module reference can be built from the sources in the docs folder with Sphinx. It is also available on-line

Support

Help support Gdspy development by donating via PayPal

History of changes

Version 0.8.1 (May 6, 2016)

• New fast_boolean function based on the Clipper library with much better performance than the old boolean.
• Changed offset signature to also use the Clipper library (this change breaks compatibility with previous versions).
• Bug fix for error when importing some labels from GDSII files.

Version 0.7.1 (June 26, 2015)

• Rebased to GitHub.
• Changed source structure and documentation.

Version 0.7 (June 12, 2015)

• New feature: offset function.
• New GdsPrint class for incremental GDSII creation (thanks to Jack Sankey for the contribution).

Version 0.6 (March 31, 2014)

• Default number of points for Round, Path.arc, and Path.turn changed to resolution of 0.01 drawing units.
• Path.parametric accepts callable final_distance and final_width for non-linear tapering.
• Added argument ends to PolyPath.
• Added (limited) support for PATHTYPE in GdsImport.
• A warning is issued when a Path curve has width larger than twice its radius (self-intersecting polygon).
• Added a random offset to the patterns in LayoutViewer.
• LayoutViewer shows cell labels for referenced cells.
• get_polygons returns (referenced) cell name if depth < 1 and by_spec is True.
• Bug fix in get_bounding_box when empty cells are referenced.
• Bug fixes in GdsImport and many speed improvements in bounding box calculations (thanks to Gene Hilton for the patch).

Version 0.5 (October 30, 2013) - NOT COMPATIBLE WITH PREVIOUS VERSIONS

• Major LayoutViewer improvements (not backwards compatible).
• The layer argument has been repositioned in the argument list in all functions (not backwards compatible).
• Renamed argument by_layer to by_spec (not backwards compatible).
• Error is raised for polygons with more vertices than possible in the GDSII format.
• Removed the global state variable for default datatype.
• Added get_datatypes to Cell.
• Added argument single_datatype to Cell.flatten.
• Removed gds_image and dropped the optional PIL dependency.

Version 0.4.1 (June 5, 2013)

• Added argument axis_offset to Path.segment allowing creation of asymmetric tapers.
• Added missing argument x_reflection to Label.
• Created a global state variable to override the default datatype.
• Bug fix in CellArray.get_bounding_box (thanks to George McLean for the fix)

Version 0.4 (October 25, 2012)

• Cell.get_bounding_box returns None for empty cells.
• Added a cache for bounding boxes for faster computation, especially for references.
• Added support for text elements with Label class.
• Improved the emission of warnings.
• Added a tolerance parameter to boolean.
• Added better print descriptions to classes.
• Bug fixes in boolean involving results with multiple holes.

Version 0.3.1 (May 24, 2012)

• Bug fix in the fracture method for PolygonSet.

Version 0.3a (May 03, 2012)

• Bug fix in the fracture method for Polygon and PolygonSet.

Version 0.3 (April 25, 2012)

• Support for Python 3.2 and 2.7
• Further improvements to the boolean function via caching.
• Added methods get_bounding_box and get_layers to Cell.
• Added method top_level to GdsImport.
• Added support for importing GDSII path elements.
• Added an argument to control the verbosity of the import function.
• Layer -1 (referenced cells) sent to the bottom of the layer list by default in LayoutViewer
• The text and background of the layer list in LayoutViewer now reflect the colors of the outlines and canvas backgroung.
• Changed default background color in LayoutViewer
• Thanks to Gene Hilton for the contributions!

Version 0.2.9 (December 14, 2011)

• Attribute Cell.cell_list changed to Cell.cell_dict.
• Changed the signature of the operation in boolean.
• Order of cells passed to LayoutViewer is now respected in the GUI.
• Complete re-implementation of the boolean function as a C extension for improved performance.
• Removed precision argument in boolean. It is fixed at 1e-13 for merging close points, otherwise machine precision is used.
• gds_image now accepts cell names as input.
• Added optional argument depth to get_polygons
• Added option to convert layers and datatypes in imported GDSII cells.
• Argument exclude_layers from LayoutViewer changed to hidden_layers and behavior changed accordingly.
• Shift + Right-clicking on a layer the layer-list of LayoutVIewer hides/unhides all other layers.
• New buttons to zoom in and out in LayoutViewer.
• Referenced cells below a configurable depth are now represented by theirs bounding boxes in LayoutViewer.

Version 0.2.8 (June 21, 2011)

• GDSII file import
• GDSII output automatically include required referenced cells.
• gds_print also accepts file name as input.
• Outlines are visible by default in LayoutViewer.
• Added background color option in LayoutViewer.
• Right-clicking on the layer list hides/unhides the target layer in LayoutViewer.
• Cell.cell_list is now a dictionary indexed by name, instead of a list.
• Added option to exclude created cells from the global list of cells kept in Cell.cell_list.
• CellReference and CellArray accept name of cells as input.
• Submodules lost their own __version__.

Version 0.2.7 (April 2, 2011)

• Bug fixed in the boolean, which affected the way polygons with more vertices then the maximum were fractured.
• gds_image accepts an extra color argument for the image background.
• Screenshots takes from LayoutViewer have the same background color as the viewer.
• The functions boolean and slice now also accept CellReference and CellArray as input.
• Added the method fracture to Polygon and PolygonSet to automatically slice polygons into parts with a predefined maximal number of vertices.
• Added the method fillet to Polygon and PolygonSet to round corners of polygons.

Version 0.2.6 (February 28, 2011)

• When saving a GDSII file, ValueError is raised if cell names are duplicated.
• Save screenshot from LayoutViewer.
• gds_image accepts cells, instead of lists.
• Outlines supported by gds_image.
• LayoutViewer stores bounding box information for all visited layers to save rendering time.

Version 0.2.5 (December 10, 2010)

• Empty cells no longer break the LayoutViewer.
• Removed the gds_view function, superseded by the LayoutViewer, along with all dependencies to matplotlib.
• Fixed a bug in boolean which affected polygons with series of collinear vertices.
• Added a function to slice polygons along straight lines parallel to an axis.

Version 0.2.4 (September 04, 2010)

• Added shortcut to Extents in LayoutViewer: Home or a keys.
• PolygonSet is the new base class for Round, which might bring some incompatibility issues with older scripts.
• Round elements, PolyPath, L1Path, and Path arc, turn and parametric sections are now automatically fractured into pieces defined by a maximal number of points.
• Default value for max_points in boolean changed to 199.
• Removed the flag to disable the warning about polygons with more than 199 vertices. The warning is shown only for Polygon and PolygonSet.
• Fixed a bug impeding parallel parametric paths to change their distance to each other.

Version 0.2.3 (August 09, 2010)

• Added the PolyPath class to easily create paths with sharp corners.
• Allow None as item in the colors parameter of LayoutViewer to make layers invisible.
• Added color outline mode to LayoutViewer (change outline color with the shift key pressed)
• Increased the scroll region of the LayoutViewer canvas
• Added a fast scroll mode: control + drag 2nd mouse button
• Created a new sample script

Version 0.2.2 (July 29, 2010)

• Changed the cursor inside LayoutViewer to standard arrow.
• Fixed bugs with the windows version of LayoutViewer (mouse wheel and ruler tool).

Version 0.2.1 (July 29, 2010)

• Bug fix: gds_image displays an error message instead of crashing when PIL is not found.
• Added class LayoutViewer, which uses Tkinter (included in all Python distributions) to display the GDSII layout with better controls then the gds_view function. This eliminates the matplotlib requirement for the viewer functionality.
• New layer colors extending layers 0 to 63.

Version 0.2.0 (July 19, 2010)

• Fixed a bug on the turn method of Path.
• Fixed a bug on the boolean function that would give an error when not using Polygon or PolygonSet as input objects.
• Added the method get_polygons to Cell, CellReference and CellArray.
• Added a copy method to Cell.
• Added a flatten method to Cell to remove references (or array references) to other cells.
• Fracture boolean output polygons based on the number of vertices to respect the 199 GDSII limit.

Version 0.1.9 (June 04, 2010)

• Added L1Path class for Manhattan geometry (L1 norm) paths.

Version 0.1.8 (May 10, 2010)

• Removed the argument fill from gds_view and added a more flexible one: style.
• Fixed a rounding error on the boolean operator affecting polygons with holes.
• Added a rotate method to PolygonSet.
• Added a warning when PolygonSet has more than 199 points
• Added a flag to disable the warning about polygons with more than 199 points.
• Added a turn method to Path, which is easier to use than arc.
• Added a direction attribute to Path to keep the information used by the segment and turn methods.

Version 0.1.7 (April 12, 2010)

• New visualization option: save the geometry directly to an image file (lower memory use).
• New functionality added: boolean operations on polygons (polygon clipping).
• All classes were adapted to work with the boolean operations.
• The attribute size in the initializer of class Text does not have a default value any longer.
• The name of the argument format in the function gds_view was changed to fill (to avoid confusion with the built-in function format).

Version 0.1.6 (December 15, 2009)

• Sample script now include comments and creates an easier to understand GDSII example.
• Improved floating point to integer rounding, which fixes the unit errors at the last digit of the precision in the GDSII file.
• Fixed the font for character 5.
• Added a flag to gds_view to avoid the automatic call to matplotlib.pyplot.show().
• In gds_view, if a layer number is greater than the number of formats defined, the formats are cycled.

Version 0.1.5a (November 15, 2009)

• Class Text correctly interprets \n and \t characters.
• Better documentation format, using the Sphinx engine and the numpy format.

Version 0.1.4 (October 5, 2009)

• Class Text re-written with a different font with no overlaps and correct size.

Version 0.1.3a (July 29 2009)

• Fixed the function to_gds of class Rectangle.

Version 0.1.3 (July 27, 2009)

• Added the datatype field to all elements of the GDSII structure.

Version 0.1.2 (July 11, 2009)

• Added the gds_view function to display the GDSII structure using the matplotlib module.
• Fixed a rotation bug in the CellArray class.
• Module published under the GNU General Public License (GPL)

Version 0.1.1 (May 12, 2009)

• Added attribute cell_list to class Cell to hold a list of all Cell created.
• Set the default argument cells=Cell.cell_list in the function gds_print.
• Added member to calculate the area for each element type.
• Added member to calculate the total area of a Cell or the area by layer.
• Included the possibility of creating objects in user-defined units, not only nanometers.

Version 0.1.0 (May 1, 2009)

• Initial release.