Phiflow

New features:
- TensorFlow: Seamless TensorFlow data pipeline integration, standard U-net architecture in `phi.tf.standard_networks`, CUDA resampling operator
- Improved support for point clouds and sampled fields (`SampledField`), RK4 advection
- Symbolic field math, `Noise` field to replace `math.randfreq()`
- Support for `STICKY` / `NO_SLIP` domain boundaries and moving/rotating obstacles
- Web interface: Quad view, improved color maps and more configuration settings, configurable axis order using `physics_config.x_first()`

Breaking changes:
- Change in `math.resample()` for `'constant'` boundaries. This affects only values sampled close to the boundary.
- Inflows now use antialiased geometry by default.
- (minor) Removed keyword arguments from `Field.at()` and `Field.sample_at()`.
- (minor) `Scene.copy_calling_script()` now has different keyword arguments.
- (minor) `GeometryMask` only holds one `Geometry` and behaves in line with `AnalyticField`.
- (minor) `math.resample()`: No longer accepts boundary `'zero'` as an alias for `'constant'`.

Deprecations:
- `load_state()`: Use `build_graph_input()` instead.
- `buoyancy()`: Use `density * -gravity * factor` in conjunction with `Field.at()` instead.
- `StaggeredGrid.from_scalar()`: Use `Field.at()` instead.
- `world.add_all()`: Use `world.add()` instead.
- `Dataset.add(), Dataset.remove()`: Mutable datasets are not supported.
- `Geometry.value_at()`: Use `Geometry.lies_inside()` instead.
- `union_mask()`: Use `mask(union())` instead.

This is the last official version with Python 2 and Python 3 support.

Version Highlights:
- Periodic pressure solve
- Improved structs: `content_type`, global item context, batched structs

Breaking Changes:
- (minor) Removed `item_condition` argument from `placeholder()`. Use the context item condition instead.
- (minor) `CenteredGrid.dtype` now returns a `CenteredGrid`. Same for `StaggeredGrid`.
- (minor) Passing `item_condition=None` anywhere now uses the context item condition. Use `item_condition=ALL_ITEMS` to iterate over all items.
- (minor) `StructBackend` now validates returned values by default. Replace it with `StructBackend(target_content_type=struct.INVALID)` to revert to old behavior.

Deprecations:
- `math.types`: Use `Struct.dtype` instead.
- `StateCollection.default_physics`
- `struct.unsafe()`: Set `content_type` to non-data instead.

Pull request https://github.com/tum-pbs/PhiFlow/pull/10

Version Highlights:
- Experimental support for PyTorch oprations
- Add struct traits
- Add ConstantVelocity

Breaking Changes: None

Deprecations:
- `TFApp`: Use `LearningApp` instead
- `CollectiveState`: Use `StateCollection` instead
- `Fan`: Use `Accelerator` instead

Pull request https://github.com/tum-pbs/PhiFlow/pull/5

Version Highlights:
- **GUI-2.0**: Improved web interface with multiple pages and experimental 3D WebGL renderer
- **Documentation**: Google Colab notebooks and better demo descriptions

Breaking Changes: None

Deprecations:
- `App.stride`: Use framerate instead of stride in App constructor
- `world.add`: Explicitly create a Physics object when adding a state to the world.

Pull request https://github.com/tum-pbs/PhiFlow/pull/2

This is the first public version of Φ-Flow.

Version Highlights:
- MIT license
- Travis-CI for automated testing

Φ-Flow 1.0.0 has built-in support for the following simulations:
- Burgers' equation in 1D, 2D, 3D
- Incompressible fluids in n-d
- Heat equation in 1D, 2D, 3D
- Schrödinger equation in 2D


Pre-release versions

Major refactoring was performed before release, renaming (among others): Smoke → Fluid, anytype → unsafe.

Version 0.4 introduced the Field API, bringing with it a new data layout for staggered grids.

Version 0.3 introduced structs and used them to split state and physics into different objects. It made the channel order (ZYX) consistent with the first dimension pointing upward.