rootvg-tessellation 0.2.0

Tessellate paths into a RootVG mesh primitive
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99

// The following code was copied and modified from
// https://github.com/iced-rs/iced/blob/31d1d5fecbef50fa319cabd5d4194f1e4aaefa21/graphics/src/geometry/stroke.rs
// Iced license (MIT): https://github.com/iced-rs/iced/blob/31d1d5fecbef50fa319cabd5d4194f1e4aaefa21/LICENSE

use rootvg_core::color::PackedSrgb;

use crate::fill::FillStyle;

/// The style of a stroke.
#[derive(Debug, Clone)]
pub struct Stroke<'a> {
    /// The color or gradient of the stroke.
    ///
    /// By default, it is set to a [`Style::Solid`] with [`Color::BLACK`].
    pub style: FillStyle,
    /// The distance between the two edges of the stroke.
    pub width: f32,
    /// The shape to be used at the end of open subpaths when they are stroked.
    pub line_cap: LineCap,
    /// The shape to be used at the corners of paths or basic shapes when they
    /// are stroked.
    pub line_join: LineJoin,
    /// The dash pattern used when stroking the line.
    pub line_dash: LineDash<'a>,
}

impl<'a> Stroke<'a> {
    /// Sets the color of the [`Stroke`].
    pub fn with_color(self, color: PackedSrgb) -> Self {
        Stroke {
            style: FillStyle::Solid(color),
            ..self
        }
    }

    /// Sets the width of the [`Stroke`].
    pub fn with_width(self, width: f32) -> Self {
        Stroke { width, ..self }
    }

    /// Sets the [`LineCap`] of the [`Stroke`].
    pub fn with_line_cap(self, line_cap: LineCap) -> Self {
        Stroke { line_cap, ..self }
    }

    /// Sets the [`LineJoin`] of the [`Stroke`].
    pub fn with_line_join(self, line_join: LineJoin) -> Self {
        Stroke { line_join, ..self }
    }
}

impl<'a> Default for Stroke<'a> {
    fn default() -> Self {
        Stroke {
            style: FillStyle::Solid(PackedSrgb([0.0, 0.0, 0.0, 1.0])),
            width: 1.0,
            line_cap: LineCap::default(),
            line_join: LineJoin::default(),
            line_dash: LineDash::default(),
        }
    }
}

/// The shape used at the end of open subpaths when they are stroked.
#[derive(Debug, Clone, Copy, Default)]
pub enum LineCap {
    /// The stroke for each sub-path does not extend beyond its two endpoints.
    #[default]
    Butt,
    /// At the end of each sub-path, the shape representing the stroke will be
    /// extended by a square.
    Square,
    /// At the end of each sub-path, the shape representing the stroke will be
    /// extended by a semicircle.
    Round,
}

/// The shape used at the corners of paths or basic shapes when they are
/// stroked.
#[derive(Debug, Clone, Copy, Default)]
pub enum LineJoin {
    /// A sharp corner.
    #[default]
    Miter,
    /// A round corner.
    Round,
    /// A bevelled corner.
    Bevel,
}

/// The dash pattern used when stroking the line.
#[derive(Debug, Clone, Copy, Default)]
pub struct LineDash<'a> {
    /// The alternating lengths of lines and gaps which describe the pattern.
    pub segments: &'a [f32],

    /// The offset of [`LineDash::segments`] to start the pattern.
    pub offset: usize,
}