1use super::*;
2use super::{Drawable, PointCollection};
3use crate::style::{Color, ShapeStyle, SizeDesc};
4use plotters_backend::{BackendCoord, DrawingBackend, DrawingErrorKind};
5
6/**
7A common trait for elements that can be interpreted as points: A cross, a circle, a triangle marker...
8
9This is used internally by Plotters and should probably not be included in user code.
10See [`EmptyElement`] for more information and examples.
11*/
12pub trait PointElement<Coord, Size: SizeDesc> {
13 /**
14 Point creator.
15
16 This is used internally by Plotters and should probably not be included in user code.
17 See [`EmptyElement`] for more information and examples.
18 */
19 fn make_point(pos: Coord, size: Size, style: ShapeStyle) -> Self;
20}
21
22/**
23A cross marker for visualizing data series.
24
25See [`EmptyElement`] for more information and examples.
26*/
27pub struct Cross<Coord, Size: SizeDesc> {
28 center: Coord,
29 size: Size,
30 style: ShapeStyle,
31}
32
33impl<Coord, Size: SizeDesc> Cross<Coord, Size> {
34 /**
35 Creates a cross marker.
36
37 See [`EmptyElement`] for more information and examples.
38 */
39 pub fn new<T: Into<ShapeStyle>>(coord: Coord, size: Size, style: T) -> Self {
40 Self {
41 center: coord,
42 size,
43 style: style.into(),
44 }
45 }
46}
47
48impl<'a, Coord: 'a, Size: SizeDesc> PointCollection<'a, Coord> for &'a Cross<Coord, Size> {
49 type Point = &'a Coord;
50 type IntoIter = std::iter::Once<&'a Coord>;
51 fn point_iter(self) -> std::iter::Once<&'a Coord> {
52 std::iter::once(&self.center)
53 }
54}
55
56impl<Coord, DB: DrawingBackend, Size: SizeDesc> Drawable<DB> for Cross<Coord, Size> {
57 fn draw<I: Iterator<Item = BackendCoord>>(
58 &self,
59 mut points: I,
60 backend: &mut DB,
61 ps: (u32, u32),
62 ) -> Result<(), DrawingErrorKind<DB::ErrorType>> {
63 if let Some((x, y)) = points.next() {
64 let size = self.size.in_pixels(&ps);
65 let (x0, y0) = (x - size, y - size);
66 let (x1, y1) = (x + size, y + size);
67 backend.draw_line((x0, y0), (x1, y1), &self.style)?;
68 backend.draw_line((x0, y1), (x1, y0), &self.style)?;
69 }
70 Ok(())
71 }
72}
73
74/**
75A triangle marker for visualizing data series.
76
77See [`EmptyElement`] for more information and examples.
78*/
79pub struct TriangleMarker<Coord, Size: SizeDesc> {
80 center: Coord,
81 size: Size,
82 style: ShapeStyle,
83}
84
85impl<Coord, Size: SizeDesc> TriangleMarker<Coord, Size> {
86 /**
87 Creates a triangle marker.
88
89 See [`EmptyElement`] for more information and examples.
90 */
91 pub fn new<T: Into<ShapeStyle>>(coord: Coord, size: Size, style: T) -> Self {
92 Self {
93 center: coord,
94 size,
95 style: style.into(),
96 }
97 }
98}
99
100impl<'a, Coord: 'a, Size: SizeDesc> PointCollection<'a, Coord> for &'a TriangleMarker<Coord, Size> {
101 type Point = &'a Coord;
102 type IntoIter = std::iter::Once<&'a Coord>;
103 fn point_iter(self) -> std::iter::Once<&'a Coord> {
104 std::iter::once(&self.center)
105 }
106}
107
108impl<Coord, DB: DrawingBackend, Size: SizeDesc> Drawable<DB> for TriangleMarker<Coord, Size> {
109 fn draw<I: Iterator<Item = BackendCoord>>(
110 &self,
111 mut points: I,
112 backend: &mut DB,
113 ps: (u32, u32),
114 ) -> Result<(), DrawingErrorKind<DB::ErrorType>> {
115 if let Some((x, y)) = points.next() {
116 let size = self.size.in_pixels(&ps);
117 let points = [-90, -210, -330]
118 .iter()
119 .map(|deg| f64::from(*deg) * std::f64::consts::PI / 180.0)
120 .map(|rad| {
121 (
122 (rad.cos() * f64::from(size) + f64::from(x)).ceil() as i32,
123 (rad.sin() * f64::from(size) + f64::from(y)).ceil() as i32,
124 )
125 });
126 backend.fill_polygon(points, &self.style.color.to_backend_color())?;
127 }
128 Ok(())
129 }
130}
131
132impl<Coord, Size: SizeDesc> PointElement<Coord, Size> for Cross<Coord, Size> {
133 fn make_point(pos: Coord, size: Size, style: ShapeStyle) -> Self {
134 Self::new(pos, size, style)
135 }
136}
137
138impl<Coord, Size: SizeDesc> PointElement<Coord, Size> for TriangleMarker<Coord, Size> {
139 fn make_point(pos: Coord, size: Size, style: ShapeStyle) -> Self {
140 Self::new(pos, size, style)
141 }
142}
143
144impl<Coord, Size: SizeDesc> PointElement<Coord, Size> for Circle<Coord, Size> {
145 fn make_point(pos: Coord, size: Size, style: ShapeStyle) -> Self {
146 Self::new(pos, size, style)
147 }
148}
149
150impl<Coord, Size: SizeDesc> PointElement<Coord, Size> for Pixel<Coord> {
151 fn make_point(pos: Coord, _: Size, style: ShapeStyle) -> Self {
152 Self::new(pos, style)
153 }
154}
155