CHANGELOG.md

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

Unreleased

Added

Changed

1.4.1 - 2022-6-13

Fixed

• Bug in plotting polarization of a nomral incidence source for some angle_phi.
• Bloch vector values required to be real rather than complex.
• Web security mitigation.

1.4.0 - 2022-6-3

Fixed

• Bug in plotting when alpha is turned off in permittivity overlay.
• Bug in plotting polarization of an angled incidence source (S,P -> P,S).
• Throw warning if user tries to download data instances in yaml or json format.
• Arrow length plotting issues for infinite sources.
• Issues with nonuniform mesh not extending exactly to simulation boundaries.

Added

• Bloch periodic boundary conditions, enabling modeling of angled plane wave.
• GeometryGroup object to associate several Geometry intances in a single Structure leading to improved performance for many objects.
• Ability to uniquely specify boundary conditions on all 6 Simulation boundaries.
• Options in field montitors for spatial downsampling and evaluation at yee grid centers.
• BatchData.load() can load the data for a batch directly from a directory.
• Utility for updating Simulation objects from old versions of Tidy3d to current version.
• Explicit web. functions for downloading only simulation.json and tidy3d.log files.

Changed

• Batch objects automatically download their json file upon download and load.
• Uses shapely instead of gdspy to merge polygons from a gds cell.
• ComponentModeler (S matrix tool) stores the Batch rather than the BatchData.
• Custom caching of properties to speed up subsequent calculations.
• Tidy3d configuration now done through setting attributes of tidy3d.config object.

1.3.3 - 2022-5-18

Fixed

• Bug in Cylinder.inside when axis != 2.

Added

• AstigmaticGaussianBeam source.

Changed

• Internal functions that may require hashing the simulation many times now use a make_static decorator. This pre-computes the simulation hash and stores it, and makes sure that the simulation has not changed at the beginning and end of the function execution.
• Speeding up initialization of PolySlab when there is no dilation or slant angle.
• Allow customizing data range that colormap covers in plot_field.
• Speeding up of the automatic grid generation using Rtree and other improvements.
• Better handling of http response errors.
• In web.monitor, the estimated cost is only displayed when available; avoid "Unable to get cost" warning.
• In PolySlab.from_gds, the selected polygons are first merged if possible, before the PolySlab-s are made. This avoids bugs e.g. in the case of slanted walls.

1.3.2 - 2022-4-30

Fixed

• Bug in nonuniform mesh where the simulation background medium may be taken into account if higher than other structures overriding it.

1.3.1 - 2022-4-29

Added

Changed

• The copy() method of Tidy3d components is deep by default.
• Maximum allowed number of distinct materials is now 65530.

Fixed

• Monitor/source opacity values also applied to associated arrows.
• Auto meshing in the presence of symmetries ignores anything outside of the main symmetry quadrant.
• If an interface is completely covered by another structure, it is ignored by the mesher.

1.3.0 - 2022-4-26

Added

• New grid_spec Field in Simulation that allows more flexibility in defining the mesh.
• GridSpec1d class defining how the meshing along each dimension should be done, with sublcasses UniformGrid and CustomGrid that cover the functionality previously offered by supplying a float or a list of floats to Simulation.grid_size. New functionality offered by AutoGrid subclass, with the mesh automatically generated based on the minimum required steps per wavelength.
• New PointDipole source.
• Opacity kwargs for monitor and source in sim.plot.
• Separated plotly-based requirements from core requrements file, can be added with "pip install tidy3d-beta[plotly]".

Changed

• Simulation.grid_spec uses the default GridSpec, which has AutoGrid(min_steps_per_wvl=10) in each direction. To initialize a Simulation then it is no longer needed to provide grid information, if sources are added to the simulation. Otherwise an error will be raised asking to provide a wavelength for the auto mesh.
• VolumeSource is now called UniformCurrentSource.
• S-matrix module now places the monitors exactly at the port locations and offsets the source slightly for numerical reasons (more accurate).
• Fixed bug in PolySlab visualization with sidewalls.
• Inheritance structure of Source reorganized.
• Better handling of only one td.inf in Box.from_bounds.
• Added proper label to intensity plots.
• Made all attributes Field() objects in data.py to clean up docs.
• Proper handling of Medium.eps_model at frequency of td.inf and None.

Removed

• Simulation.grid_size is removed in favor of Simulation.grid_spec.

1.2.2 - 2022-4-16

Added

• SimulationDataApp GUI for visualizing contents of SimulationData in tidy3d.plugings.
• SimulationPlotly interface for generating Simulation.plot() figures using plotly instead of matplotlib.
• New PermittivityMonitor and PermittivityData to store the complex relative permittivity as used in the simulation.
• The maximum credit cost for a simulation can now be queried using web.estimate_cost. It is also displayed by default during web.upload.

Changed

• Faster plotting for matplotlib and plotly.
• SimulationData normalization keeps track of source index and can be normalized when loading directly from .hdf5 file.
• Monitor data with symmetries now store the minimum required data to file and expands the symmetries on the fly.
• Significant speedup in plotting complicated simulations without patch transparency.
• When a list of dl is provided as a grid_size along a given direction, the grid is placed such that the total size np.sum(dl) is centered at the simulation center. Previously, a grid boundary was always placed at the simulation center.

1.2.1 - 2022-3-30

Added

Changed

• webapi functions now only authenticate when needed.
• Credentials storing folder only created when needed.
• Added maximum number of attemtps in authentication.
• Made plotly plotting faster.
• Cached Simulation.medium and Simulation.medium_map computation.

1.2.0 - 2022-3-28

Added

• PolySlab geometries support dilation and angled sidewalls.
• Percent done monitoring of jobs running longer than 10 seconds.
• Can use vectorized spherical coordinates in tidy3d.plugins.Near2Far.
• ModeSolver returns a ModeSolverData object similar to SimulationData, containing all the information about the modes.
• ModeFieldMonitor and ModeFieldData allow the results of a mode solve run server-side to be stored.
• Plotting of ModeFieldData fields in SimulationData.plot_field and ModeSolverData.plot_field.
• Ordering of modes by polarization fraction can be specified in ModeSpec.
• Angled mode sources.

Changed

• Significant speed improvement for Near2Far calculations.
• freq no longer passed to ModeSolver upon init, instead a list of freqs passed to ModeSolver.solve.
• Mode solver now returns ModeSolverData object containing information about the mode fields and propagation constants as data arrays over frequency and mode index.
• Reorganized some of the internal Source classes.
• Major improvements to Batch objects. Batch.run() returns a BatchData object that maps task_name to SimulationData.
• Infinity stored as str in json outputs, conforming to json file specifications.
• No longer need to specify one of x/y/z in SimulationData.plot_field if the monitor has a zero-sized dimension.
• Simulation.run_time but must be > 0 to upload to server.

1.1.1 - 2022-3-2

Added

Changed

• Fixed issue where smatrix was not uploaded to pyPI.

1.1.0 - 2022-3-1

Added

• Simulation symmetries now fully functional.
• Ability to perform near-to-far transformations from multiple surface monitors oriented along the x, y or z directions using tidy3d.plugins.Near2Far.
• tidy3d.plugins.ComponentModeler tool for scattering matrix calculations.

Changed

• Major enhancements to near field to far field transformation tool: multiple monitors supported with arbitrary configuration, user control over sampling point density.
• Fixed visualization bug in symmetry.

1.0.2 - 2022-2-24

Added

• Clarified license terms to not include scripts written using the tidy3d python API.
• Simulation symmetries are now enabled but currently only affect the mode solver, if the mode plane lies on the simulation center and there's a symmetry.
• Validator that mode objects with symmetries are either entirely in the main quadrant, or lie on the symmetry axis.
• Simulation.plotly() makes a plotly figure of the cross section.
• Dispersion fitter can parse urls from refractiveindex.info
• Clarified license terms to not include scripts written using the tidy3d python API.

Changed

• Fixed a bug in python 3.6 where polyslab vertices loaded differently from file.

1.0.1 - 2022-2-16

Added

• Selmeier.from_dispersion() method to quickly make a single-pole fit for lossless weakly dispersive materials.
• Stable dispersive material fits via webservice.
• Allow to load dispersive data directly by providing URL to txt or csv file
• Validates simulation based on discretized size.

Changed

• Polyslab.from_gds returns a list of PolySlab objects imported from all polygons in given layer and dtype, can optionally specify single dtype.
• Warning about structure close to PML disabled if Absorber type.
• Source dft now ignores insignificant time amplitudes for speed.
• New color schemes for plots.

1.0.0 - 2022-1-31

Added

• Stable dispersive material fits via webservice.

Changed

• Refined and updated documentation.

0.2.0 - 2022-1-29

Added

• FieldMonitor.surface() to split volume monitors into their surfaces.
• Units and annotation to data.
• Faster preprocessing.
• Web authentication using environment variables TIDY3D_USER and TIDY3D_PASS.
• callback_url in web API to put job metadata when a job is finished.
• Support for non uniform grid size definition.
• Gaussian beam source.
• Automated testing through tox and github actions.

0.1.1 - 2021-11-09

Added

• PML parameters and padding Grid with pml pixels by @momchil-flex in #64
• Documentation by @tylerflex in #63
• Gds import from @tylerflex in #69
• Loggin by @tylerflex in #70
• Multi-pole Drude medium by @weiliangjin2021 in #73
• Mode Solver: from @tylerflex in #74
• Near2Far from @tylerflex in #77

Changed

• Separated docs from @tylerflex in #78

0.1.0 - 2021-10-21

Added

• Web API implemented by converting simulations to old tidy3D

Alpha Release Changes

22.1.1

• Solver speed improvement (gain depending on simulation + hardware details).
• Bringing the speed of the non-angled mode solver back to pre-21.4.2 levels.

21.4.4

• Improvements to subpixel averaging for dispersive materials.
• Enabled web login using environment variables TIDY3D_USER and TIDY3D_PASS.

21.4.3

• Bugfix when running simulation with zero run_time.
• More internal logging.
• Fixed unstable 'Li1993_293K' variant of cSi in the material library.

21.4.2.2

• Bugfix when downloading data on Windows.
• Bugfix in material fitting tool when target tolerance is not reached.

21.4.2

• New Gaussian beam source and example usage <examples/GratingCoupler.html>__.
• Modal sources and monitors in bent and in angled waveguides with tutorial <examples/Modes_bent_angled.html>__.
• Nyquist-limit sampling in frequency-domain monitors (much faster without loss of accuracy).
• Support for Drude model of material dispersion.
• Small bugfixes to some of the other dispersion models.
• PEC boundaries applied by default at the truncation of any boundary with PML, avoiding potential issues with using periodic boundaries under the PML instead.
• Source normalization no longer adding a spurious frequency-dependent phase to the fields.
• Fixed bug in unpacking monitor fields with symmetries and interpolate=False.
• Lots of streamlining on the backend side.

21.4.1

• Fixed bug with zero-size monitor plotting.
• Fixed bug with empty simulation run introduced in 21.4.0.

21.4.0

• A few small fixes.

21.3.1.6

• Fixed nonlinear constraint in dispersive material fitting tool.
• Fixed potential issue when a monitor stores neither 'E' nor 'H'.
• Fixed some backwards compatibility issues introduced in 21.3.1.5.

21.3.1.5

• Frequency monitors can now optionally store the complex permittivity at the same locations where the E-fields are recorded, at the monitor frequencies.
• Frequency monitors now also have an 'interpolate' keyword, which defaults to True and reproduces the behavior of previous versions. If set to False, however, the raw fields evaluated at their corresponding Yee grid locations are returned, instead of the fields interpolated to the Yee cell centers. This also affects the returned permittivity, if requested.
• Reorganized internal source time dependence handling, enabling more complicated functionality in the future, like custom source time.
• Total field in the simulation now sampled at the time step of the peak of the source time dependence, for better estimation of the shutoff factor.
• A number of bug fixes, especially in the new plotting introduced in 21.3.1.4.

21.3.1.4

• Reorganized plotting:
• Speeding up structure visualizations.
• Structures now shown based on primitive definitions rather than grid discretization. This then shows the physical structures but not what the simulation "sees". Will add an option to display the grid lines in next version.
• Bumped down matplotlib version requirement to 3.2 and python version requirement to 3.6.
• Improved handling of PEC interfaces.- Reorganized and extended internal logging.
• Added tidy3d.__version__.
• A number of fixes to the example notebooks and the colab integration.

21.3.1.3

• Bumping back python version requirement from 3.8 to 3.7.

21.3.1.2

• Hotfix to an internal bug in some simulation runs.

21.3.1.1

• New dispersion fitting tool for material data and accompanying tutorial <examples/Fitting.html>__.
• (beta) Non-uniform Cartesian meshing now supported. The grid coordinates are provided by hand to Simulation. Next step is implementing auto-meshing.
• DispersionModel objects can now be directly used as materials.
• Fixed bug to Cylinder subpixel averaging.
• Small bugs fixes/added checks for some edge cases.

21.3.1.0

• Rehash of symmetries and support for mode sources and monitors with symmetries.
• Anisotropic materials (diagonal epsilon tensor).
• Rehashed error handling to output more runtime errors to tidy3d.log.
• Job and Batch classes for better simulation handling (eventually to fully replace webapi functions).
• A large number of small improvements and bug fixes.