ggplot_rs/scale/
mod.rs

1pub mod alpha;
2pub mod color;
3pub mod continuous;
4pub mod datetime;
5pub mod discrete;
6pub mod format;
7pub mod gradient;
8pub mod gradient_n;
9pub mod grey;
10pub mod linetype;
11pub mod linetype_manual;
12pub mod manual;
13pub mod palettes;
14pub mod scale_set;
15pub mod sec_axis;
16pub mod shape;
17pub mod shape_manual;
18pub mod size;
19pub mod transform;
20pub mod util;
21
22pub use scale_set::ScaleSet;
23
24use crate::aes::Aesthetic;
25use crate::data::Value;
26use crate::render::backend::{Linetype, PointShape};
27
28/// Trait for scales that map data values to visual properties.
29pub trait Scale: Send + Sync {
30    /// Which aesthetic this scale is for.
31    fn aesthetic(&self) -> Aesthetic;
32
33    /// Incorporate data values to determine domain.
34    fn train(&mut self, values: &[Value]);
35
36    /// Map a data value to a [0, 1] normalized position (position scales)
37    /// or to a concrete visual value index (color/size scales).
38    fn map(&self, value: &Value) -> f64;
39
40    /// Generate break positions and labels for axis/legend.
41    fn breaks(&self) -> Vec<(f64, String)>;
42
43    /// Human-readable name (axis title).
44    fn name(&self) -> &str;
45
46    /// Set the scale name.
47    fn set_name(&mut self, name: &str);
48
49    /// Apply transformation to raw data (e.g., log10).
50    fn transform(&self, value: &Value) -> Value {
51        value.clone()
52    }
53
54    /// Whether this is a discrete scale.
55    fn is_discrete(&self) -> bool {
56        false
57    }
58
59    /// Map a data value to an RGB color. Default returns None.
60    fn map_to_color(&self, _value: &Value) -> Option<(u8, u8, u8)> {
61        None
62    }
63
64    /// Map a data value to a point shape. Default returns None.
65    fn map_to_shape(&self, _value: &Value) -> Option<PointShape> {
66        None
67    }
68
69    /// Map a data value to a linetype. Default returns None.
70    fn map_to_linetype(&self, _value: &Value) -> Option<Linetype> {
71        None
72    }
73
74    /// Map a data value to a point size (radius in pixels). Default returns None.
75    fn map_to_size(&self, _value: &Value) -> Option<f64> {
76        None
77    }
78
79    /// Map a data value to an alpha (opacity) value. Default returns None.
80    fn map_to_alpha(&self, _value: &Value) -> Option<f64> {
81        None
82    }
83
84    /// Get the secondary axis specification, if any.
85    fn sec_axis(&self) -> Option<&sec_axis::SecAxis> {
86        None
87    }
88
89    /// Override the trained domain limits (used by coord_cartesian zoom).
90    fn set_limits(&mut self, _min: f64, _max: f64) {
91        // Default no-op. Continuous scales override this.
92    }
93
94    /// Return OOB filter limits if this scale was created with explicit limits
95    /// (e.g., via xlim/ylim). Data outside these limits should be removed before stats.
96    fn filter_limits(&self) -> Option<(f64, f64)> {
97        None
98    }
99
100    /// Return the trained data domain (min, max) for continuous scales.
101    /// Used by the colorbar legend to pass data-space values to map_to_color().
102    fn domain(&self) -> Option<(f64, f64)> {
103        None
104    }
105
106    /// Clone this scale into a boxed trait object.
107    fn clone_box(&self) -> Box<dyn Scale>;
108
109    /// Reset training state so the scale can be retrained on new data.
110    fn reset_training(&mut self) {}
111}
ggplot_rs/scale/mod.rs

ggplot_rs/scale/
mod.rs
