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ggplot_rs/geom/
jitter.rs

1use crate::aes::Aesthetic;
2use crate::coord::Coord;
3use crate::data::DataFrame;
4use crate::position::jitter::PositionJitter;
5use crate::position::Position;
6use crate::render::backend::{DrawBackend, PointShape, PointStyle};
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/// Jittered scatter plot — like GeomPoint but with PositionJitter by default.
16pub struct GeomJitter {
17    pub size: f64,
18    pub color: (u8, u8, u8),
19    pub alpha: f64,
20    /// Horizontal jitter (data units); `None` = 0.4 × data resolution.
21    pub width: Option<f64>,
22    /// Vertical jitter (data units); `None` = 0.4 × data resolution.
23    pub height: Option<f64>,
24}
25
26impl Default for GeomJitter {
27    fn default() -> Self {
28        GeomJitter {
29            size: 3.0,
30            color: (0, 0, 0),
31            alpha: 1.0,
32            width: None,
33            height: None,
34        }
35    }
36}
37
38impl Geom for GeomJitter {
39    fn draw(
40        &self,
41        data: &DataFrame,
42        coord: &dyn Coord,
43        scales: &ScaleSet,
44        _theme: &Theme,
45        backend: &mut dyn DrawBackend,
46    ) -> Result<(), RenderError> {
47        let x_col = data
48            .column("x")
49            .ok_or(RenderError::MissingAesthetic("x".into()))?;
50        let y_col = data
51            .column("y")
52            .ok_or(RenderError::MissingAesthetic("y".into()))?;
53        let color_col = data.column("color");
54        let size_col = data.column("size");
55        let alpha_col = data.column("alpha");
56        let shape_col = data.column("shape");
57
58        let plot_area = backend.plot_area();
59        let x_scale = scales.get(&Aesthetic::X);
60        let y_scale = scales.get(&Aesthetic::Y);
61
62        for i in 0..data.nrows() {
63            let nx = x_scale.map(|s| s.map(&x_col[i])).unwrap_or(0.0);
64            let ny = y_scale.map(|s| s.map(&y_col[i])).unwrap_or(0.0);
65            let (px, py) = coord.transform((nx, ny), &plot_area);
66
67            let (r, g, b) = if let Some(cc) = color_col {
68                scales
69                    .map_color(&Aesthetic::Color, &cc[i])
70                    .unwrap_or(self.color)
71            } else {
72                self.color
73            };
74
75            let alpha = alpha_col.and_then(|c| c[i].as_f64()).unwrap_or(self.alpha);
76            let size = size_col.and_then(|c| c[i].as_f64()).unwrap_or(self.size);
77            let shape = shape_col
78                .and_then(|c| scales.map_shape(&c[i]))
79                .unwrap_or(PointShape::Circle);
80
81            backend.draw_shape(
82                (px, py),
83                size,
84                &PointStyle {
85                    color: (r, g, b),
86                    alpha,
87                    filled: true,
88                    shape,
89                },
90            )?;
91        }
92
93        Ok(())
94    }
95
96    fn required_aes(&self) -> Vec<Aesthetic> {
97        vec![Aesthetic::X, Aesthetic::Y]
98    }
99
100    fn default_stat(&self) -> Box<dyn Stat> {
101        Box::new(StatIdentity)
102    }
103
104    fn default_position(&self) -> Box<dyn Position> {
105        Box::new(PositionJitter {
106            width: self.width,
107            height: self.height,
108            ..PositionJitter::default()
109        })
110    }
111
112    fn default_params(&self) -> GeomParams {
113        GeomParams::default()
114    }
115
116    fn name(&self) -> &str {
117        "jitter"
118    }
119
120    fn set_series_color(&mut self, color: (u8, u8, u8)) {
121        self.color = color;
122    }
123}