lyon_tessellation/lib.rs
1#![doc(html_logo_url = "https://nical.github.io/lyon-doc/lyon-logo.svg")]
2#![deny(bare_trait_objects)]
3#![deny(unconditional_recursion)]
4#![allow(clippy::float_cmp)]
5#![allow(clippy::too_many_arguments)]
6#![no_std]
7
8// TODO: Tessellation pipeline diagram needs to be updated.
9
10//! Tessellation of 2D fill and stroke operations.
11//!
12//! <svg viewBox="0 0 600.0 300.0" height="300" width="600">
13//! <g transform="translate(0,-752.36216)">
14//! <path style="fill:none;stroke:#ff9955;" d="m 346.4,790.7 186.8,11.2 -213.6,25.9 196.8,12.7 -185.1,41.4 192.4,24.4 -205.5,10.3 194.1,33.4 -97.3,25.5 -96.9,-58.9"/>
15//! <path style="fill:#ffb380;stroke:none;" d="m 59.1,965.3 -15.1,-48.7 13.0,-34.4 -11.5,-54.2 26.7,-37.1 73.2,-19.2 114.4,30.4 -17.0,38.0 1.1,15.3 13.4,-8.1 14.8,6.8 -5.2,48.2 -16.8,4.8 -11.4,43.5 -40.4,29.9 -31.3,-3.0 0,28.2 19.0,8.3 -44.2,19.0 -10.6,-25.1 9.9,-3.8 0,-28.2 z"/>
16//! <path style="fill:#de8787;stroke:none;" d="m 106.4,853.1 2.2,67.9 49.6,0.7 13.7,-22.9 -20.6,-3.8 -4.5,-44.2 -17.5,-13.7 z"/>
17//! <path style="fill:#a02c2c;stroke:none;" d="m 108.74845,940.94089 61.08369,3.05419 -13.74383,15.27092 -33.59604,-3.05418 z"/>
18//! <path style="fill:#784421;stroke:none;" d="m 176.93475,845.6345 20.51653,4.85918 -5.39908,30.7748 -12.68786,-1.88968 z"/>
19//! <path style="fill:#784421;stroke:none;" d="m 78.4,882.0 9.4,-3.2 3.7,-30.7 -13.2,8.6 z"/>
20//! <path style="fill:none;stroke:#ff9955;stroke-linecap:round;stroke-linejoin:round;" d="m 333.2,965.3 -15.1,-48.7 13.0,-34.4 -11.5,-54.2 26.7,-37.1 73.2,-19.2 114.4,30.4 -17.0,38.0 1.2,15.3 13.2,-8.0 14.8,6.8 -5.2,48.2 -16.8,4.8 -11.4,43.5 -40.4,29.9 -31.3,-3.0 0,28.2 19.0,8.3 -44.2,19.0 -10.6,-25.1 9.9,-3.8 0,-28.2 z"/>
21//! <path style="fill:none;stroke:#de8787;stroke-linecap:round;stroke-linejoin:round;" d="m 380.5,853.1 2.2,67.9 49.6,0.7 13.7,-22.9 -20.6,-3.8 -4.5,-44.2 -17.5,-13.7 z"/>
22//! <path style="fill:none;stroke:#a02c2c;stroke-linecap:round;stroke-linejoin:round;" d="m 382.8,940.9 61.0,3.0 -13.7,15.2 -33.5,-3.0 z"/>
23//! <path style="fill:none;stroke:#803300;stroke-linecap:round;stroke-linejoin:round;" d="m 451.0,845.6 20.5,4.8 -5.3,30.7 -12.6,-1.8 z"/>
24//! <path style="fill:none;stroke:#803300;stroke-linecap:round;stroke-linejoin:round;" d="m 352.5,882.0 9.4,-3.2 3.7,-30.7 -13.2,8.6 z"/>
25//! <path style="fill:none;stroke:#803300;stroke-linecap:round;stroke-linejoin:round;" d="m 352.5,856.4 9.3,22.2"/>
26//! <path style="fill:none;stroke:#de8787;stroke-linecap:round;stroke-linejoin:round;" d="m 380.8,853.3 40.2,-2.5 -38.3,70.1 42.6,-25.9 6.6,26.5"/>
27//! <path style="fill:none;stroke:#803300;stroke-linecap:round;stroke-linejoin:round;" d="m 471.4,850.4 -17.6,28.6"/>
28//! <path style="fill:none;stroke:#a02c2c;stroke-linecap:round;stroke-linejoin:round;" d="m 443.3,943.9 -46.7,12.2"/>
29//! <path style="fill:none;stroke:#ff9955;stroke-linecap:round;stroke-linejoin:round;" d="m 540.7,902.0 -22.5,-46.9 5.7,51.7"/>
30//! <path style="fill:none;stroke:#ff9955;stroke-linecap:round;stroke-linejoin:round;" d="m 512.2,950.2 -71.0,27.1 -26.1,-1.7 25.3,30.1 -25.1,-1.7 44.0,10.3 -53.8,-6.1"/>
31//! <path style="fill:none;stroke:#ff9955;stroke-linecap:round;stroke-linejoin:round;" d="m 518.5,8.3 27.5,-1.2"/>
32//! </g>
33//! </svg>
34//!
35//! This crate is reexported in [lyon](https://docs.rs/lyon/).
36//!
37//! ## Overview
38//!
39//! The most interesting types and traits of this crate are:
40//!
41//! * [FillTessellator](struct.FillTessellator.html) - Tessellator for complex path fill operations.
42//! * [StrokeTessellator](struct.StrokeTessellator.html) - Tessellator for complex path stroke operations.
43//! * [`GeometryBuilder`](geometry_builder/trait.GeometryBuilder.html) - (See the documentation of the
44//! [geometry_builder module](geometry_builder/index.html)) which the above two are built on. This trait
45//! provides an interface for types that help with building and assembling the vertices and triangles that
46//! form the tessellation, usually in the form of arbitrary vertex and index buffers.
47//!
48//! ## The tessellation pipeline
49//!
50//! <svg xmlns="http://www.w3.org/2000/svg" width="280mm" height="42mm" viewBox="0 0 280 42">
51//! <defs>
52//! <marker id="e" orient="auto" overflow="visible">
53//! <path fill="#59f" fill-rule="evenodd" stroke="#59f" stroke-width=".532" d="M-4 0l-2 2 7-2-7-2z"/>
54//! </marker>
55//! <marker id="d" orient="auto" overflow="visible">
56//! <path fill-rule="evenodd" stroke="#000" stroke-width=".532" d="M-4 0l-2 2 7-2-7-2z"/>
57//! </marker>
58//! <marker id="c" orient="auto" overflow="visible">
59//! <path fill="#59f" fill-rule="evenodd" stroke="#59f" stroke-width=".532" d="M-4 0l-2 2 7-2-7-2z"/>
60//! </marker>
61//! <marker id="b" orient="auto" overflow="visible">
62//! <path fill-rule="evenodd" stroke="#000" stroke-width=".532" d="M-4 0l-2 2 7-2-7-2z"/>
63//! </marker>
64//! <marker id="a" orient="auto" overflow="visible">
65//! <path fill-rule="evenodd" stroke="#000" stroke-width=".532" d="M-4 0l-2 2 7-2-7-2z"/>
66//! </marker>
67//! </defs>
68//! <path fill="#fff" stroke="#000" stroke-opacity=".56" stroke-width=".26" stroke-miterlimit="4.27" d="M39.55 17.37h15.8l2.15-1.7 2.06 1.7h15.36V38.8H39.55zM194.65 31.3h21.58l2.1-1.83 2.04 1.82h35.07v7.07h-60.8zM77.7 19.5h54.6l3.3-2.58 3.17 2.57h52.56v19H77.7z" color="#000" overflow="visible" stroke-linecap="round" stroke-linejoin="round"/>
69//! <g color="#000">
70//! <path fill="#80b3ff" d="M194.6 20.37h50.65v8.73H194.6z" overflow="visible"/>
71//! <path fill="#d5f6ff" d="M194.6 19.3h50.65v8.74H194.6z" overflow="visible"/>
72//! </g>
73//! <g color="#000">
74//! <path fill="#2a7fff" d="M221.6 5.74h21.56v8.73H221.6z" overflow="visible"/>
75//! <path fill="#d5f6ff" d="M221.6 4.68h21.56v8.73H221.6z" overflow="visible"/>
76//! </g>
77//! <g color="#000">
78//! <path fill="#2a7fff" d="M154.38 5.74h47.4v8.73h-47.4z" overflow="visible"/>
79//! <path fill="#d5f6ff" d="M154.38 4.68h47.4v8.73h-47.4z" overflow="visible"/>
80//! </g>
81//! <g color="#000">
82//! <path fill="#2a7fff" d="M91.94 5.74h39.34v8.73H91.94z" overflow="visible"/>
83//! <path fill="#d5f6ff" d="M91.94 4.68h39.34v8.73H91.94z" overflow="visible"/>
84//! </g>
85//! <g color="#000">
86//! <path fill="#2a7fff" d="M3.04 5.74H75.2v8.73H3.03z" overflow="visible"/>
87//! <path fill="#d5f6ff" d="M3.04 4.68H75.2v8.73H3.03z" overflow="visible"/>
88//! </g>
89//! <text x="93.73" y="266.09" stroke-width=".26" style="line-height:6.61458302px" font-size="5.29" font-family="Sans" letter-spacing="0" word-spacing="0" transform="translate(0 -255)">
90//! <tspan x="93.73" y="266.09">FillTessellator</tspan>
91//! </text>
92//! <text x="155.37" y="265.58" stroke-width=".26" style="line-height:6.61458302px" font-size="5.29" font-family="Sans" letter-spacing="0" word-spacing="0" transform="translate(0 -255)">
93//! <tspan x="155.37" y="265.58">GeometryBuilder</tspan>
94//! </text>
95//! <text x="223.1" y="266.02" stroke-width=".26" style="line-height:6.61458302px" font-size="5.29" font-family="Sans" letter-spacing="0" word-spacing="0" transform="translate(0 -255)">
96//! <tspan x="223.1" y="266.02">output</tspan>
97//! </text>
98//! <text x="196.17" y="280.9" stroke-width=".26" style="line-height:6.61458302px" font-size="5.29" font-family="Sans" letter-spacing="0" word-spacing="0" transform="translate(0 -255)">
99//! <tspan x="196.17" y="280.9">VertexConstructor</tspan>
100//! </text>
101//! <text x="5.13" y="266.09" stroke-width=".26" style="line-height:6.61458302px" font-size="5.29" font-family="Sans" letter-spacing="0" word-spacing="0" transform="translate(0 -255)">
102//! <tspan x="5.13" y="266.09">Iterator<PathEvent></tspan>
103//! </text>
104//! <text x="79.79" y="282.2" stroke-width=".26" style="line-height:6.61458302px" font-size="5.29" font-family="Sans" letter-spacing="0" word-spacing="0" transform="translate(0 -255)">
105//! <tspan x="79.79" y="282.2" fill="navy" font-size="4.23">builder.add_vertex(FillVertex) -> VertexId;</tspan><tspan x="79.79" y="289.09" fill="navy" font-size="4.23">builder.add_triangle(VertexId, <tspan stroke-width=".07" style="line-height:1.75010836px;font-variant-ligatures:normal;font-variant-position:normal;font-variant-caps:normal;font-variant-numeric:normal;font-variant-alternates:normal;font-variant-east-asian:normal;font-feature-settings:normal;text-indent:0;text-align:start;text-decoration-line:none;text-decoration-style:solid;text-decoration-color:#000000;text-transform:none;text-orientation:mixed;shape-padding:0" white-space="normal">VertexId, VertexId);</tspan></tspan>
106//! </text>
107//! <path fill="none" stroke="#000" stroke-width=".3" stroke-miterlimit="4.4" d="M76.94 265l13.64-.1" marker-end="url(#a)" transform="translate(0 -255)"/>
108//! <path fill="none" stroke="#000" stroke-width=".3" stroke-miterlimit="4.4" d="M132.86 265l19.55-.1" marker-end="url(#b)" transform="translate(0 -255)"/>
109//! <path fill="#59f" fill-rule="evenodd" stroke="#59f" stroke-width=".3" stroke-miterlimit="4.4" d="M203.38 264.53l8.27 8.26" marker-end="url(#c)" transform="translate(0 -255)"/>
110//! <path fill="none" stroke="#000" stroke-width=".3" stroke-miterlimit="4.4" d="M203.38 264.53l16 .06" marker-end="url(#d)" transform="translate(0 -255)"/>
111//! <text x="196.69" y="291.41" stroke-width=".26" style="line-height:6.61458302px" font-size="5.29" font-family="Sans" letter-spacing="0" word-spacing="0" transform="translate(0 -255)">
112//! <tspan x="196.69" y="291.41" fill="navy" font-size="4.23">FillVertex -> CustomVertex</tspan>
113//! </text>
114//! <path fill="#59f" fill-rule="evenodd" stroke="#59f" stroke-width=".3" stroke-miterlimit="4.4" d="M212.97 272.98l6.75-6.5" marker-end="url(#e)" transform="translate(0 -255)"/>
115//! <g fill="none" stroke="#000" stroke-width=".26">
116//! <path d="M7.2 30.1l2.98 1.72h3.24l1.78-1.8 2.62-.75 2.08 1.83-1.6 2.87-5.64 1.54-3.5-1.62zM32.6 30.1l-3 1.72H26.4l-1.78-1.8-2.62-.75-2.08 1.83 1.6 2.87 5.64 1.54 3.5-1.62zM15 20.67l-.5 4.42 1.34 1 1.63-1.57-1.06-4.03zM24.53 20.67l.5 4.42-1.33 1-1.63-1.57 1.06-4.03z"/>
117//! </g>
118//! <path fill="#b7c8c4" fill-rule="evenodd" stroke="#000" stroke-width=".15" d="M251.68 19.5l2.98 1.74h3.23l1.78-1.8 2.62-.75 2.07 1.82-1.6 2.87-5.63 1.53-3.5-1.63z" stroke-linecap="round" stroke-linejoin="round"/>
119//! <path fill="#b7c8c4" fill-rule="evenodd" stroke="#000" stroke-width=".15" d="M277.07 19.5l-2.98 1.74h-3.24l-1.8-1.8-2.6-.75-2.1 1.82L266 23.4l5.63 1.53 3.5-1.63zM259.48 10.08l-.5 4.42 1.33 1 1.65-1.55-1.07-4.03zM269 10.08l.52 4.42-1.34 1-1.64-1.55 1.07-4.03z" stroke-linecap="round" stroke-linejoin="round"/>
120//! <path fill="none" stroke="#000" stroke-width=".15" d="M258.97 14.5l2.98-.55-2.47-3.87M266.54 13.95l2.98.55-1.9-4.58M254.66 21.24l-1 2.06 4.23-2.06-.76 3.7 2.54-5.5 3.1 3.95-.48-4.7M275.1 23.3l-1-2.06-2.5 3.7-.74-3.7-4.4-2.55-.48 4.7 4.88-2.16" stroke-linecap="round" stroke-linejoin="round"/>
121//! <text x="43.5" y="277.68" stroke-width=".26" style="line-height:6.61458349px" font-size="5.29" font-family="Sans" letter-spacing="0" word-spacing="0" transform="translate(0 -255)">
122//! <tspan x="43.5" y="277.68" fill="navy" font-size="3.88">MoveTo(Point)</tspan><tspan x="43.5" y="284.66" fill="navy" font-size="3.88">LineTo(Point)</tspan><tspan x="43.5" y="291.65" fill="navy" font-size="3.88">Close</tspan>
123//! </text>
124//! </svg>
125//!
126//! The figure above shows a simplified summary of each step of the fill tessellation pipeline.
127//!
128//! ### The input: iterators
129//!
130//! The path tessellators are not tied to a particular data structure. Instead they consume
131//! iterators of flattened path events.
132//! A [Path struct](https://docs.rs/lyon_path/*/lyon_path/struct.Path.html) in the crate
133//! [lyon_path](https://docs.rs/lyon_path/*/lyon_path/) is provided for convenience
134//! (but is optional).
135//!
136//! ### The output: geometry builders
137//!
138//! The tessellators are parametrized over a type implementing the
139//! [GeometryBuilder trait](geometry_builder/trait.GeometryBuilder.html).
140//! This trait provides some simple methods to add vertices and triangles, without enforcing
141//! any particular representation for the resulting geometry. This is important because each
142//! application will usually want to work with its own vertex type tailored a certain rendering
143//! model.
144//!
145//! Applications can implement the ```GeometryBuilder<Point>``` trait in order to
146//! generate vertex buffers and index buffers with custom vertex types.
147//!
148//! The structs [VertexBuffers](geometry_builder/struct.VertexBuffers.html) and
149//! [geometry_builder::BuffersBuilder](geometry_builder/struct.BuffersBuilder.html) are provided
150//! for convenience. `VertexBuffers<T>` is contains a `Vec<T>` for the vertices and a `Vec<u16>`
151//! for the indices.
152//!
153//! `BuffersBuilder` is generic over a `VertexConstructor<InputVertex, OutputVertex>` trait which
154//! creates the application's output vertices from the tessellator input vertices (either `FillVertex`
155//! or `StrokeVertex`).
156//!
157//! ### Rendering the tessellated geometry
158//!
159//! The tessellators produce geometry in the form of vertex and index buffers which are expected
160//! to be rendered using the equivalent of OpenGL's `glDrawElements` with mode `GL_TRIANGLES` available
161//! under various names in the different graphics APIs.
162//! There is an [example](https://github.com/nical/lyon/tree/main/examples/wgpu) showing how
163//! it can be done with wgpu.
164//!
165//! ### Flattening and tolerance
166//!
167//! Most tessellators in this crate currently operate on flattened paths (paths or shapes represented
168//! by sequences of line segments). when paths contain bézier curves or arcs, the latter need to be
169//! approximated with sequences of line segments. This approximation depends on a `tolerance` parameter
170//! which represents the maximum distance between a curve and its flattened approximation.
171//!
172//! More explanation about flattening and tolerance in the [lyon_geom crate](https://docs.rs/lyon_geom/#flattening).
173//!
174//! ## Examples
175//!
176//! - [Tessellating path fills](fill/struct.FillTessellator.html#examples).
177//! - [Tessellating path strokes](stroke/struct.StrokeTessellator.html#examples).
178//! - [Generating custom vertices](geometry_builder/index.html#generating-custom-vertices).
179//! - [Generating completely custom output](geometry_builder/index.html#generating-a-completely-custom-output).
180//! - [Writing a tessellator](geometry_builder/index.html#writing-a-tessellator).
181//!
182
183#![allow(dead_code)]
184//#![allow(needless_return, new_without_default_derive)] // clippy
185
186extern crate alloc;
187
188#[cfg(any(test, feature = "std"))]
189extern crate std;
190
191pub use lyon_path as path;
192
193#[cfg(test)]
194use lyon_extra as extra;
195
196#[cfg(feature = "serialization")]
197#[macro_use]
198pub extern crate serde;
199
200mod basic_shapes;
201mod error;
202mod event_queue;
203mod fill;
204pub mod geometry_builder;
205mod math_utils;
206mod monotone;
207mod stroke;
208
209#[cfg(test)]
210#[rustfmt::skip]
211mod earcut_tests;
212#[cfg(test)]
213mod fill_tests;
214#[cfg(test)]
215mod fuzz_tests;
216
217pub use crate::path::math;
218
219pub use crate::path::geom;
220
221#[doc(inline)]
222pub use crate::event_queue::*;
223
224#[doc(inline)]
225pub use crate::fill::*;
226
227#[doc(inline)]
228pub use crate::stroke::*;
229
230#[doc(inline)]
231pub use crate::geometry_builder::{
232 BuffersBuilder, FillGeometryBuilder, FillVertexConstructor, GeometryBuilder,
233 GeometryBuilderError, StrokeGeometryBuilder, StrokeVertexConstructor, VertexBuffers,
234};
235
236#[doc(inline)]
237pub use crate::error::*;
238
239pub use crate::path::{AttributeIndex, Attributes, FillRule, LineCap, LineJoin, Side};
240
241use crate::path::EndpointId;
242
243use core::ops::{Add, Sub};
244use alloc::vec::Vec;
245
246/// Before or After. Used to describe position relative to a join.
247#[derive(Copy, Clone, Debug, PartialEq)]
248#[cfg_attr(feature = "serialization", derive(Serialize, Deserialize))]
249pub(crate) enum Order {
250 Before,
251 After,
252}
253
254impl Order {
255 pub fn opposite(self) -> Self {
256 match self {
257 Order::Before => Order::After,
258 Order::After => Order::Before,
259 }
260 }
261
262 pub fn is_before(self) -> bool {
263 self == Order::Before
264 }
265
266 pub fn is_after(self) -> bool {
267 self == Order::After
268 }
269}
270
271pub use fill::FillVertex;
272pub use stroke::StrokeVertex;
273
274/// Where a vertex produced by a tessellator comes from in the original path.
275///
276/// In most cases, vertices come directly from an endpoint. However, Curve
277/// approximations and self-intersections can introduce vertices that are on
278/// one or several edges, at a certain parameter `t` between the two endpoints
279/// of the edge.
280#[derive(Copy, Clone, Debug, PartialEq)]
281pub enum VertexSource {
282 Endpoint {
283 id: EndpointId,
284 },
285 Edge {
286 from: EndpointId,
287 to: EndpointId,
288 t: f32,
289 },
290}
291
292impl VertexSource {
293 pub fn is_endpoint(&self) -> bool {
294 matches!(self, VertexSource::Endpoint { .. })
295 }
296
297 pub fn is_edge(&self) -> bool {
298 matches!(self, VertexSource::Edge { .. })
299 }
300}
301
302/// Vertical or Horizontal.
303#[derive(Copy, Clone, Debug, PartialEq)]
304#[cfg_attr(feature = "serialization", derive(Serialize, Deserialize))]
305pub enum Orientation {
306 Horizontal,
307 Vertical,
308}
309
310/// Parameters for the tessellator.
311#[derive(Copy, Clone, Debug, PartialEq)]
312#[cfg_attr(feature = "serialization", derive(Serialize, Deserialize))]
313#[non_exhaustive]
314pub struct StrokeOptions {
315 /// What cap to use at the start of each sub-path.
316 ///
317 /// Default value: `LineCap::Butt`.
318 pub start_cap: LineCap,
319
320 /// What cap to use at the end of each sub-path.
321 ///
322 /// Default value: `LineCap::Butt`.
323 pub end_cap: LineCap,
324
325 /// See the SVG specification.
326 ///
327 /// Default value: `LineJoin::Miter`.
328 pub line_join: LineJoin,
329
330 /// Line width
331 ///
332 /// Default value: `StrokeOptions::DEFAULT_LINE_WIDTH`.
333 pub line_width: f32,
334
335 /// Index of a custom attribute defining a per-vertex
336 /// factor to modulate the line width.
337 ///
338 /// Default value: `None`.
339 pub variable_line_width: Option<AttributeIndex>,
340
341 /// See the SVG specification.
342 ///
343 /// Must be greater than or equal to 1.0.
344 /// Default value: `StrokeOptions::DEFAULT_MITER_LIMIT`.
345 pub miter_limit: f32,
346
347 /// Maximum allowed distance to the path when building an approximation.
348 ///
349 /// See [Flattening and tolerance](index.html#flattening-and-tolerance).
350 /// Default value: `StrokeOptions::DEFAULT_TOLERANCE`.
351 pub tolerance: f32,
352}
353
354impl StrokeOptions {
355 /// Minimum miter limit as defined by the SVG specification.
356 ///
357 /// See [StrokeMiterLimitProperty](https://svgwg.org/specs/strokes/#StrokeMiterlimitProperty)
358 pub const MINIMUM_MITER_LIMIT: f32 = 1.0;
359 /// Default miter limit as defined by the SVG specification.
360 ///
361 /// See [StrokeMiterLimitProperty](https://svgwg.org/specs/strokes/#StrokeMiterlimitProperty)
362 pub const DEFAULT_MITER_LIMIT: f32 = 4.0;
363 pub const DEFAULT_LINE_CAP: LineCap = LineCap::Butt;
364 pub const DEFAULT_LINE_JOIN: LineJoin = LineJoin::Miter;
365 pub const DEFAULT_LINE_WIDTH: f32 = 1.0;
366 pub const DEFAULT_TOLERANCE: f32 = 0.1;
367
368 pub const DEFAULT: Self = StrokeOptions {
369 start_cap: Self::DEFAULT_LINE_CAP,
370 end_cap: Self::DEFAULT_LINE_CAP,
371 line_join: Self::DEFAULT_LINE_JOIN,
372 line_width: Self::DEFAULT_LINE_WIDTH,
373 variable_line_width: None,
374 miter_limit: Self::DEFAULT_MITER_LIMIT,
375 tolerance: Self::DEFAULT_TOLERANCE,
376 };
377
378 #[inline]
379 pub fn tolerance(tolerance: f32) -> Self {
380 Self::DEFAULT.with_tolerance(tolerance)
381 }
382
383 #[inline]
384 pub const fn with_tolerance(mut self, tolerance: f32) -> Self {
385 self.tolerance = tolerance;
386 self
387 }
388
389 #[inline]
390 pub const fn with_line_cap(mut self, cap: LineCap) -> Self {
391 self.start_cap = cap;
392 self.end_cap = cap;
393 self
394 }
395
396 #[inline]
397 pub const fn with_start_cap(mut self, cap: LineCap) -> Self {
398 self.start_cap = cap;
399 self
400 }
401
402 #[inline]
403 pub const fn with_end_cap(mut self, cap: LineCap) -> Self {
404 self.end_cap = cap;
405 self
406 }
407
408 #[inline]
409 pub const fn with_line_join(mut self, join: LineJoin) -> Self {
410 self.line_join = join;
411 self
412 }
413
414 #[inline]
415 pub const fn with_line_width(mut self, width: f32) -> Self {
416 self.line_width = width;
417 self
418 }
419
420 #[inline]
421 pub fn with_miter_limit(mut self, limit: f32) -> Self {
422 assert!(limit >= Self::MINIMUM_MITER_LIMIT);
423 self.miter_limit = limit;
424 self
425 }
426
427 #[inline]
428 pub const fn with_variable_line_width(mut self, idx: AttributeIndex) -> Self {
429 self.variable_line_width = Some(idx);
430 self
431 }
432}
433
434impl Default for StrokeOptions {
435 fn default() -> Self {
436 Self::DEFAULT
437 }
438}
439
440/// Parameters for the fill tessellator.
441#[derive(Copy, Clone, Debug, PartialEq)]
442#[cfg_attr(feature = "serialization", derive(Serialize, Deserialize))]
443#[non_exhaustive]
444pub struct FillOptions {
445 /// Maximum allowed distance to the path when building an approximation.
446 ///
447 /// See [Flattening and tolerance](index.html#flattening-and-tolerance).
448 ///
449 /// Default value: `FillOptions::DEFAULT_TOLERANCE`.
450 pub tolerance: f32,
451
452 /// Set the fill rule.
453 ///
454 /// See the [SVG specification](https://www.w3.org/TR/SVG/painting.html#FillRuleProperty).
455 ///
456 /// Default value: `EvenOdd`.
457 pub fill_rule: FillRule,
458
459 /// Whether to perform a vertical or horizontal traversal of the geometry.
460 ///
461 /// Default value: `Vertical`.
462 pub sweep_orientation: Orientation,
463
464 /// A fast path to avoid some expensive operations if the path is known to
465 /// not have any self-intersections.
466 ///
467 /// Do not set this to `false` if the path may have intersecting edges else
468 /// the tessellator may panic or produce incorrect results. In doubt, do not
469 /// change the default value.
470 ///
471 /// Default value: `true`.
472 pub handle_intersections: bool,
473}
474
475impl FillOptions {
476 /// Default flattening tolerance.
477 pub const DEFAULT_TOLERANCE: f32 = 0.1;
478 /// Default Fill rule.
479 pub const DEFAULT_FILL_RULE: FillRule = FillRule::EvenOdd;
480 /// Default orientation.
481 pub const DEFAULT_SWEEP_ORIENTATION: Orientation = Orientation::Vertical;
482
483 pub const DEFAULT: Self = FillOptions {
484 tolerance: Self::DEFAULT_TOLERANCE,
485 fill_rule: Self::DEFAULT_FILL_RULE,
486 sweep_orientation: Self::DEFAULT_SWEEP_ORIENTATION,
487 handle_intersections: true,
488 };
489
490 #[inline]
491 pub fn even_odd() -> Self {
492 Self::DEFAULT
493 }
494
495 #[inline]
496 pub fn tolerance(tolerance: f32) -> Self {
497 Self::DEFAULT.with_tolerance(tolerance)
498 }
499
500 #[inline]
501 pub fn non_zero() -> Self {
502 let mut options = Self::DEFAULT;
503 options.fill_rule = FillRule::NonZero;
504 options
505 }
506
507 #[inline]
508 pub const fn with_tolerance(mut self, tolerance: f32) -> Self {
509 self.tolerance = tolerance;
510 self
511 }
512
513 #[inline]
514 pub const fn with_fill_rule(mut self, rule: FillRule) -> Self {
515 self.fill_rule = rule;
516 self
517 }
518
519 #[inline]
520 pub const fn with_sweep_orientation(mut self, orientation: Orientation) -> Self {
521 self.sweep_orientation = orientation;
522 self
523 }
524
525 #[inline]
526 pub const fn with_intersections(mut self, intersections: bool) -> Self {
527 self.handle_intersections = intersections;
528 self
529 }
530}
531
532impl Default for FillOptions {
533 fn default() -> Self {
534 Self::DEFAULT
535 }
536}
537
538type Index = u32;
539
540/// A virtual vertex offset in a geometry.
541///
542/// The `VertexId`s are only valid between `GeometryBuilder::begin_geometry` and
543/// `GeometryBuilder::end_geometry`. `GeometryBuilder` implementations typically be translate
544/// the ids internally so that first `VertexId` after `begin_geometry` is zero.
545#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
546#[cfg_attr(feature = "serialization", derive(Serialize, Deserialize))]
547pub struct VertexId(pub Index);
548
549impl VertexId {
550 pub const INVALID: VertexId = VertexId(u32::MAX);
551
552 pub fn offset(self) -> Index {
553 self.0
554 }
555
556 pub fn to_usize(self) -> usize {
557 self.0 as usize
558 }
559
560 pub fn from_usize(v: usize) -> Self {
561 VertexId(v as Index)
562 }
563}
564
565impl Add<u32> for VertexId {
566 type Output = Self;
567 fn add(self, rhs: u32) -> Self {
568 VertexId(self.0 + rhs)
569 }
570}
571
572impl Sub<u32> for VertexId {
573 type Output = Self;
574 fn sub(self, rhs: u32) -> Self {
575 VertexId(self.0 - rhs)
576 }
577}
578
579impl From<u16> for VertexId {
580 fn from(v: u16) -> Self {
581 VertexId(v as Index)
582 }
583}
584impl From<u32> for VertexId {
585 fn from(v: u32) -> Self {
586 VertexId(v)
587 }
588}
589impl From<i32> for VertexId {
590 fn from(v: i32) -> Self {
591 VertexId(v as Index)
592 }
593}
594
595impl From<VertexId> for u16 {
596 fn from(v: VertexId) -> Self {
597 v.0 as u16
598 }
599}
600impl From<VertexId> for u32 {
601 fn from(v: VertexId) -> Self {
602 v.0
603 }
604}
605impl From<VertexId> for i32 {
606 fn from(v: VertexId) -> Self {
607 v.0 as i32
608 }
609}
610impl From<VertexId> for usize {
611 fn from(v: VertexId) -> Self {
612 v.0 as usize
613 }
614}
615
616pub(crate) struct SimpleAttributeStore {
617 data: Vec<f32>,
618 num_attributes: usize,
619 next_id: EndpointId,
620}
621
622impl path::AttributeStore for SimpleAttributeStore {
623 fn get(&self, id: EndpointId) -> Attributes {
624 let start = id.0 as usize * self.num_attributes;
625 let end = start + self.num_attributes;
626 &self.data[start..end]
627 }
628
629 fn num_attributes(&self) -> usize {
630 self.num_attributes
631 }
632}
633
634impl Default for SimpleAttributeStore {
635 fn default() -> Self {
636 SimpleAttributeStore::new(0)
637 }
638}
639
640impl SimpleAttributeStore {
641 pub fn new(num_attributes: usize) -> Self {
642 SimpleAttributeStore {
643 data: Vec::new(),
644 num_attributes,
645 next_id: EndpointId(0),
646 }
647 }
648
649 pub fn add(&mut self, attributes: Attributes) -> EndpointId {
650 debug_assert_eq!(attributes.len(), self.num_attributes);
651 self.data.extend_from_slice(attributes);
652 let id = self.next_id;
653 self.next_id.0 += 1;
654 id
655 }
656
657 pub fn reserve(&mut self, n: usize) {
658 self.data.reserve(n * self.num_attributes);
659 }
660
661 pub fn reset(&mut self, num_attributes: usize) {
662 self.data.clear();
663 self.next_id = EndpointId(0);
664 self.num_attributes = num_attributes;
665 }
666}
667
668#[test]
669fn test_without_miter_limit() {
670 let expected_limit = 4.0;
671 let stroke_options = StrokeOptions::default();
672
673 assert_eq!(expected_limit, stroke_options.miter_limit);
674}
675
676#[test]
677fn test_with_miter_limit() {
678 let expected_limit = 3.0;
679 let stroke_options = StrokeOptions::default().with_miter_limit(expected_limit);
680
681 assert_eq!(expected_limit, stroke_options.miter_limit);
682}
683
684#[test]
685#[should_panic]
686fn test_with_invalid_miter_limit() {
687 let _ = StrokeOptions::default().with_miter_limit(0.0);
688}