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Move to the 2018 edition.
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Feb 26, 2019
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nical
Move to the 2018 edition.
08d1871
| #![doc(html_logo_url = "https://nical.github.io/lyon-doc/lyon-logo.svg")] | |
| #![deny(bare_trait_objects)] | |
| //! GPU-based 2D graphics rendering tools in Rust using path tessellation. | |
| //! | |
| //!  | |
| //! | |
| //! [](https://crates.io/crates/lyon) | |
| //! [](https://travis-ci.org/nical/lyon) | |
| //! | |
| //! # Crates | |
| //! | |
| //! This meta-crate (`lyon`) reexports the following sub-crates for convenience: | |
| //! | |
| //! * [](https://crates.io/crates/lyon_tessellation) | |
| //! [](https://docs.rs/lyon_tessellation) - | |
| //! **lyon_tessellation** - Path tessellation routines. | |
| //! * [](https://crates.io/crates/lyon_path) | |
| //! [](https://docs.rs/lyon_path) - | |
| //! **lyon_path** - Tools to build and iterate over paths. | |
| //! * [](https://crates.io/crates/lyon_algorithms) | |
| //! [](https://docs.rs/lyon_algorithms) - | |
| //! **lyon_algorithms** - Various 2d path related algorithms. | |
| //! * [](https://crates.io/crates/lyon_geom) | |
| //! [](https://docs.rs/lyon_geom) - | |
| //! **lyon_geom** - 2d utilities for cubic and quadratic bézier curves, arcs and more. | |
| //! * [](https://crates.io/crates/lyon_svg) | |
| //! [](https://docs.rs/lyon_svg) - | |
| //! **lyon_svg** - Create paths using SVG's path syntax. | |
| //! * [](https://crates.io/crates/lyon_extra) | |
| //! [](https://docs.rs/lyon_extra) - | |
| //! **lyon_extra** - Additional testing and debugging tools. | |
| //! * [](https://crates.io/crates/lyon_tess2) | |
| //! [](https://docs.rs/lyon_tess2) - | |
| //! **lyon_tess2** - Alternative fill tessellation implementation using [libtess2](https://github.com/memononen/libtess2). | |
| //! | |
| //! Each `lyon_<name>` crate is reexported as a `<name>` module in `lyon`. For example: | |
| //! | |
| //! ```ignore | |
| //! extern crate lyon_tessellation; | |
| //! use lyon_tessellation::FillTessellator; | |
| //! ``` | |
| //! | |
| //! Is equivalent to: | |
| //! | |
| //! ```ignore | |
| //! extern crate lyon; | |
| //! use lyon::tessellation::FillTessellator; | |
| //! ``` | |
| //! | |
| //! # Feature flags | |
| //! | |
| //! serialization using serde can be enabled on each crate using the | |
| //! `serialization` feature flag (disabled by default). | |
| //! | |
| //! When using the main crate `lyon`, the `lyon_svg`, `lyon_tess2` and | |
| //! `lyon_extra` dependencies are disabled by default. They can be added | |
| //! with the feature flags `svg`, `tess2` and `extra`. | |
| //! | |
| //! # Additional documentation and links | |
| //! | |
| //! * [very basic gfx-rs example](https://github.com/nical/lyon/tree/master/examples/gfx_basic). | |
| //! * [advanced gfx-rs example](https://github.com/nical/lyon/tree/master/examples/gfx_advanced). | |
| //! * There is some useful documentation on the project's [wiki](https://github.com/nical/lyon/wiki). | |
| //! * The source code is available on the project's [git repository](https://github.com/nical/lyon). | |
| //! * Interested in contributing? Pull requests are welcome. If you would like to help but don't know | |
| //! what to do specifically, have a look at the [github issues](https://github.com/nical/lyon/issues), | |
| //! some of which are tagged as [easy](https://github.com/nical/lyon/issues?q=is%3Aissue+is%3Aopen+label%3Aeasy). | |
| //! | |
| //! # Examples | |
| //! | |
| //! ## Tessellating a rounded rectangle | |
| //! | |
| //! The `lyon_tessellation` crate provides a collection of tessellation routines | |
| //! for common shapes such as rectangles and circles. Let's have a look at how | |
| //! to obtain the fill tessellation a rectangle with rounded corners: | |
| //! | |
| //! ``` | |
| //! use lyon::math::rect; | |
| //! use lyon::tessellation::{VertexBuffers, FillOptions, FillVertex}; | |
| //! use lyon::tessellation::basic_shapes::*; | |
| //! use lyon::tessellation::geometry_builder::simple_builder; | |
| //! | |
| //! fn main() { | |
| //! let mut geometry: VertexBuffers<FillVertex, u16> = VertexBuffers::new(); | |
| //! | |
| //! let options = FillOptions::tolerance(0.1); | |
| //! | |
| //! fill_rounded_rectangle( | |
| //! &rect(0.0, 0.0, 100.0, 50.0), | |
| //! &BorderRadii { | |
| //! top_left: 10.0, | |
| //! top_right: 5.0, | |
| //! bottom_left: 20.0, | |
| //! bottom_right: 25.0, | |
| //! }, | |
| //! &options, | |
| //! &mut simple_builder(&mut geometry), | |
| //! ); | |
| //! | |
| //! // The tessellated geometry is ready to be uploaded to the GPU. | |
| //! println!(" -- {} vertices {} indices", | |
| //! geometry.vertices.len(), | |
| //! geometry.indices.len() | |
| //! ); | |
| //! } | |
| //! | |
| //! ``` | |
| //! | |
| //! ## Building and tessellating an arbitrary path | |
| //! | |
| //! ``` | |
| //! extern crate lyon; | |
| //! use lyon::math::point; | |
| //! use lyon::path::Path; | |
| //! use lyon::path::builder::*; | |
| //! use lyon::tessellation::*; | |
| //! | |
| //! fn main() { | |
| //! // Build a Path. | |
| //! let mut builder = Path::builder(); | |
| //! builder.move_to(point(0.0, 0.0)); | |
| //! builder.line_to(point(1.0, 0.0)); | |
| //! builder.quadratic_bezier_to(point(2.0, 0.0), point(2.0, 1.0)); | |
| //! builder.cubic_bezier_to(point(1.0, 1.0), point(0.0, 1.0), point(0.0, 0.0)); | |
| //! builder.close(); | |
| //! let path = builder.build(); | |
| //! | |
| //! // Let's use our own custom vertex type instead of the default one. | |
| //! #[derive(Copy, Clone, Debug)] | |
| //! struct MyVertex { position: [f32; 2], normal: [f32; 2] }; | |
| //! | |
| //! // Will contain the result of the tessellation. | |
| //! let mut geometry: VertexBuffers<MyVertex, u16> = VertexBuffers::new(); | |
| //! | |
| //! let mut tessellator = FillTessellator::new(); | |
| //! | |
| //! { | |
| //! // Compute the tessellation. | |
| //! tessellator.tessellate_path( | |
| //! &path, | |
| //! &FillOptions::default(), | |
| //! &mut BuffersBuilder::new(&mut geometry, |vertex : FillVertex| { | |
| //! MyVertex { | |
| //! position: vertex.position.to_array(), | |
| //! normal: vertex.normal.to_array(), | |
| //! } | |
| //! }), | |
| //! ).unwrap(); | |
| //! } | |
| //! | |
| //! // The tessellated geometry is ready to be uploaded to the GPU. | |
| //! println!(" -- {} vertices {} indices", | |
| //! geometry.vertices.len(), | |
| //! geometry.indices.len() | |
| //! ); | |
| //! } | |
| //! ``` | |
| //! | |
| //! ## What is the tolerance variable in these examples? | |
| //! | |
| //! The tessellator operates on flattened paths (that only contains line segments) | |
| //! so we have to approximate the curves segments with sequences of line segments. | |
| //! To do so we pick a tolerance threshold which is the maximum distance allowed | |
| //! between the curve and its approximation. | |
| //! The documentation of the [lyon_geom](https://docs.rs/lyon_geom) crate provides | |
| //! more detailed explanations about this tolerance parameter. | |
| //! | |
| //! ## Rendering the tessellated geometry | |
| //! | |
| //! Lyon does not provide with any GPU abstraction or rendering backend (for now). | |
| //! It is up to the user of this crate to decide whether to use OpenGL, vulkan, gfx-rs, | |
| //! glium, or any low level graphics API and how to render it. | |
| //! The [basic](https://github.com/nical/lyon/tree/master/examples/gfx_basic) and | |
| //! [advanced](https://github.com/nical/lyon/tree/master/examples/gfx_advanced) gfx-rs | |
| //! examples can be used to get an idea of how to render the geometry (in this case | |
| //! using gfx-rs). | |
| //! | |
| pub extern crate lyon_tessellation; | |
| pub extern crate lyon_algorithms; | |
| #[cfg(feature = "extra")] pub extern crate lyon_extra; | |
| #[cfg(feature = "svg")] pub extern crate lyon_svg; | |
| #[cfg(feature = "libtess2")] pub extern crate lyon_tess2; | |
| pub use lyon_tessellation as tessellation; | |
| pub use lyon_algorithms as algorithms; | |
| pub use tessellation::path as path; | |
| pub use tessellation::geom as geom; | |
| #[cfg(feature = "svg")] pub use lyon_svg as svg; | |
| #[cfg(feature = "extra")] pub use lyon_extra as extra; | |
| #[cfg(feature = "libtess2")] pub use lyon_tess2 as tess2; | |
| pub use geom::math; |