ggplot_rs/geom/
errorbar.rs

1use crate::aes::Aesthetic;
2use crate::coord::Coord;
3use crate::data::DataFrame;
4use crate::position::identity::PositionIdentity;
5use crate::position::Position;
6use crate::render::backend::{DrawBackend, LineStyle, Linetype};
7use crate::render::RenderError;
8use crate::scale::ScaleSet;
9use crate::stat::identity::StatIdentity;
10use crate::stat::Stat;
11use crate::theme::Theme;
12
13use super::{Geom, GeomParams};
14
15/// Error bar geometry — vertical bars with whisker caps.
16pub struct GeomErrorbar {
17    pub color: (u8, u8, u8),
18    pub width: f64,
19    pub cap_width: f64,
20    pub alpha: f64,
21}
22
23impl Default for GeomErrorbar {
24    fn default() -> Self {
25        GeomErrorbar {
26            color: (0, 0, 0),
27            width: 1.0,
28            cap_width: 0.03,
29            alpha: 1.0,
30        }
31    }
32}
33
34impl Geom for GeomErrorbar {
35    fn draw(
36        &self,
37        data: &DataFrame,
38        coord: &dyn Coord,
39        scales: &ScaleSet,
40        _theme: &Theme,
41        backend: &mut dyn DrawBackend,
42    ) -> Result<(), RenderError> {
43        let x_col = data
44            .column("x")
45            .ok_or(RenderError::MissingAesthetic("x".into()))?;
46        let ymin_col = data
47            .column("ymin")
48            .ok_or(RenderError::MissingAesthetic("ymin".into()))?;
49        let ymax_col = data
50            .column("ymax")
51            .ok_or(RenderError::MissingAesthetic("ymax".into()))?;
52
53        let plot_area = backend.plot_area();
54        let x_scale = scales.get(&Aesthetic::X);
55        let y_scale = scales.get(&Aesthetic::Y);
56
57        let style = LineStyle {
58            color: self.color,
59            alpha: self.alpha,
60            width: self.width,
61            linetype: Linetype::Solid,
62        };
63
64        for i in 0..data.nrows() {
65            let nx = x_scale.map(|s| s.map(&x_col[i])).unwrap_or(0.0);
66            let ny_min = y_scale.map(|s| s.map(&ymin_col[i])).unwrap_or(0.0);
67            let ny_max = y_scale.map(|s| s.map(&ymax_col[i])).unwrap_or(0.0);
68
69            let (cx, top) = coord.transform((nx, ny_max), &plot_area);
70            let (_, bottom) = coord.transform((nx, ny_min), &plot_area);
71
72            // Vertical bar
73            backend.draw_line(&[(cx, top), (cx, bottom)], &style)?;
74
75            // Top cap
76            let (cap_l, _) = coord.transform((nx - self.cap_width, ny_max), &plot_area);
77            let (cap_r, _) = coord.transform((nx + self.cap_width, ny_max), &plot_area);
78            backend.draw_line(&[(cap_l, top), (cap_r, top)], &style)?;
79
80            // Bottom cap
81            let (cap_l, _) = coord.transform((nx - self.cap_width, ny_min), &plot_area);
82            let (cap_r, _) = coord.transform((nx + self.cap_width, ny_min), &plot_area);
83            backend.draw_line(&[(cap_l, bottom), (cap_r, bottom)], &style)?;
84        }
85
86        Ok(())
87    }
88
89    fn required_aes(&self) -> Vec<Aesthetic> {
90        vec![Aesthetic::X, Aesthetic::Ymin, Aesthetic::Ymax]
91    }
92
93    fn default_stat(&self) -> Box<dyn Stat> {
94        Box::new(StatIdentity)
95    }
96    fn default_position(&self) -> Box<dyn Position> {
97        Box::new(PositionIdentity)
98    }
99    fn default_params(&self) -> GeomParams {
100        GeomParams::default()
101    }
102    fn name(&self) -> &str {
103        "errorbar"
104    }
105
106    fn set_series_color(&mut self, color: (u8, u8, u8)) {
107        self.color = color;
108    }
109}
ggplot_rs/geom/errorbar.rs

ggplot_rs/geom/
errorbar.rs
