# vtkio A parser and writer for the Visualization Toolkit (VTK) [file formats](https://kitware.github.io/vtk-examples/site/VTKFileFormats/). [![On crates.io](https://img.shields.io/crates/v/vtkio.svg)](https://crates.io/crates/vtkio) [![On docs.rs](https://docs.rs/vtkio/badge.svg)](https://docs.rs/vtkio/) [![Build Status](https://github.com/elrnv/vtkio/workflows/CI/badge.svg)](https://github.com/elrnv/vtkio/actions) This is meant to be a feature complete parser of Legacy and XML VTK file formats. Both serial and parallel XML file formats are supported. The Legacy format parser is written using [nom](https://crates.io/crates/nom). XML VTK files are import and exported with [`quick-xml`](https://crates.io/crates/quick-xml) and [`serde`](https://crates.io/crates/serde) crates. # Usage To use this library simply add the crate name to your `Cargo.toml` file: ```rust [dependencies] vtkio = "0.7" ``` ## Examples Many sample files can be found in the `assets` directory. Below are some examples for using this library. ### Import/Export Below we load a VTK file named `tet.vtk`, modify it and write it back in Legacy ASCII format. ```rust use vtkio::model::*; // import model definition of a VTK file fn main() { use std::path::PathBuf; let file_path = PathBuf::from("assets/tet.vtk"); let mut vtk_file = Vtk::import(&file_path) .expect(&format!("Failed to load file: {:?}", file_path)); vtk_file.version = Version::new((4,2)); // arbitrary change vtk_file.export_ascii(&file_path) .expect(&format!("Failed to save file: {:?}", file_path)); } ``` The next two examples show how to create new `Vtk` instances manually. ### Simple triangular cell Here, we create a Vtk instance containing a single triangle represented as a cell of an unstructured grid. ```rust fn make_triangle() -> Vtk { Vtk { version: Version { major: 4, minor: 2 }, title: String::new(), byte_order: ByteOrder::BigEndian, file_path: None, data: DataSet::inline(UnstructuredGridPiece { points: IOBuffer::F64(vec![ // coordinates of node 0 -1.0, -1.0, 0.0, // coordinates of node 1 1.0, -1.0, 0.0, // coordinates of node 2 1.0, 1.0, 0.0, ]), cells: Cells { cell_verts: VertexNumbers::XML { // connect node 0, 1, 2 (in this order) connectivity: vec![0, 1, 2], // only one group of size 3 offsets: vec![3], }, // only one cell of type triangle types: vec![CellType::Triangle; 1], }, data: Attributes { ..Default::default() }, }), } } ``` ### Mixing Cell Types The following example creates a mesh with a triangle and a quadrilateral. ```rust fn make_mixed_flat_elements() -> Vtk { Vtk { version: Version { major: 4, minor: 2 }, title: String::new(), byte_order: ByteOrder::BigEndian, file_path: None, data: DataSet::inline(UnstructuredGridPiece { points: IOBuffer::F64(vec![ -1.0, -1.0, 0.0, 1.0, -1.0, 0.0, 1.0, 1.0, 0.0, -1.0, 1.0, 0.0, 2.0, -1.0, 0.2, 2.0, 1.0, 0.2, ]), cells: Cells { cell_verts: VertexNumbers::XML { connectivity: vec![ // nodes of triangle 0, 1, 2, // nodes of quadrilateral 1, 4, 5, 2, ], offsets: vec![ // number of nodes cell 1 3, // number of nodes cell 1 + number of nodes of cell 2 // 3 + 4 = 7 7 ], }, types: vec![ CellType::Triangle, CellType::Quad ], }, data: Attributes { ..Default::default() }, }), } } ``` ### Extract field data Once a Vtk file is read or loaded from a file, it is useful to extract useful data from it. In the following snippet, an "id" field attached to vertices is extracted from a Vtk struct. ```rust fn extract_id_field(vtk: Vtk) -> Vec { let pieces = if let DataSet::UnstructuredGrid { pieces, .. } = vtk.data { pieces } else { panic!("Wrong vtk data type"); }; // If piece is already inline, this just returns a piece data clone. let piece = pieces[0].load_piece_data(None).expect("Failed to load piece data"); let attribute = &piece.data.point[0]; if let Attribute::Field { data_array, .. } = attribute { data_array .iter() .find(|&DataArrayBase { name, .. }| name == "id") .expect("Failed to find id field") .data .cast_into::() .expect("Failed cast") } else { panic!("No field attribute found"); } } ``` ## Features There are two main features available: - XML File support via the `xml` feature flag (enabled by default). This allows importing and exporting VTK files in the modern XML format. If disabled, only the legacy file format is supported, however the build is faster since it does not include additional dependencies (`serde` and `quick-xml`) and code needed to parse and write XML files. - Compression via the `compression` feature flag (enabled by default). This flag exposes additional APIs to export and import compressed VTK files (only for XML format). This feature has no benefit when the `xml` feature is disabled. To disable the features above simply set `default-features` to `false`. To enable a specific feature add it to the list under `features`. For instance to disable only the `compression` feature, add the `vtkio` dependency as ```rust [dependencies] vtkio = { version = "0.7", default-features = false, features = ["xml"] } ``` To disable all additional features use ```rust [dependencies] vtkio = { version = "0.7", default-features = false } ``` # Changes Version 0.3 of the crate supports only Legacy VTK formats. For a list of changes introduced in the new versions of `vtkio` (v0.4+) see the [CHANGELOG](CHANGELOG.md). # License This repository is licensed under either of * Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or https://www.apache.org/licenses/LICENSE-2.0) * MIT License ([LICENSE-MIT](LICENSE-MIT) or https://opensource.org/licenses/MIT) at your option. Unless You explicitly state otherwise, any Contribution intentionally submitted for inclusion in the Work by You, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.