ggplot_rs/scale/
scale_set.rs

1use crate::aes::Aesthetic;
2use crate::data::{DataFrame, Value};
3use crate::render::backend::{Linetype, PointShape};
4use crate::scale::alpha::ScaleAlphaContinuous;
5use crate::scale::color::{ScaleColorContinuous, ScaleColorDiscrete};
6use crate::scale::continuous::ScaleContinuous;
7use crate::scale::datetime::ScaleDateTime;
8use crate::scale::discrete::ScaleDiscrete;
9use crate::scale::linetype::ScaleLinetypeDiscrete;
10use crate::scale::linewidth::ScaleLinewidthContinuous;
11use crate::scale::shape::ScaleShapeDiscrete;
12use crate::scale::size::ScaleSizeContinuous;
13
14use super::Scale;
15
16/// Registry of all scales for a plot. Handles auto-detection and training.
17pub struct ScaleSet {
18    scales: Vec<Box<dyn Scale>>,
19}
20
21impl ScaleSet {
22    pub fn new() -> Self {
23        ScaleSet { scales: Vec::new() }
24    }
25
26    /// Add a user-specified scale.
27    pub fn add(&mut self, scale: Box<dyn Scale>) {
28        // Replace existing scale for same aesthetic
29        let aes = scale.aesthetic();
30        self.scales.retain(|s| s.aesthetic() != aes);
31        self.scales.push(scale);
32    }
33
34    /// Give every scale the plot-level default locale (scales with their own
35    /// locale keep it; scales without numeric/date labels ignore it).
36    pub fn set_default_locale(&mut self, locale: &crate::locale::Locale) {
37        for s in &mut self.scales {
38            s.set_default_locale(locale);
39        }
40    }
41
42    /// Get a scale for a specific aesthetic.
43    pub fn get(&self, aes: &Aesthetic) -> Option<&dyn Scale> {
44        self.scales
45            .iter()
46            .find(|s| s.aesthetic() == *aes)
47            .map(|s| s.as_ref())
48    }
49
50    /// Get mutable scale for a specific aesthetic.
51    pub fn get_mut(&mut self, aes: &Aesthetic) -> Option<&mut Box<dyn Scale>> {
52        self.scales.iter_mut().find(|s| s.aesthetic() == *aes)
53    }
54
55    /// Ensure a scale exists for a given aesthetic. Auto-detect type from data.
56    pub fn ensure_scale(&mut self, aes: &Aesthetic, data: &DataFrame) {
57        if self.get(aes).is_some() {
58            return;
59        }
60        // OHLC values live on the y scale (via the geom's ymin/ymax extents);
61        // they get no scale of their own.
62        if matches!(
63            aes,
64            Aesthetic::Open
65                | Aesthetic::High
66                | Aesthetic::Low
67                | Aesthetic::Close
68                | Aesthetic::Slope
69                | Aesthetic::Intercept
70                // Reference-line intercepts live on the x / y scale; the
71                // build creates that scale from them only if no layer did
72                // (so a `geom_vline(0)` added first can't force a
73                // continuous scale onto a discrete axis).
74                | Aesthetic::Xintercept
75                | Aesthetic::Yintercept
76                // Interactive aesthetics carry their value straight through
77                // to the mark's attributes — no visual mapping, no legend.
78                | Aesthetic::Tooltip
79                | Aesthetic::DataAttr(_)
80                // Boxplot stat="identity" hinges/outliers (B3-5) live on
81                // the y scale (via `column_aesthetic`/`Y_FAMILY`/the
82                // build's stat_aes training list), not a scale of their
83                // own.
84                | Aesthetic::Lower
85                | Aesthetic::Middle
86                | Aesthetic::Upper
87                | Aesthetic::Outliers
88        ) {
89            return;
90        }
91        let values = data.column(aes.col_name());
92
93        let is_discrete = match values {
94            Some(vals) => vals
95                .iter()
96                .any(|v| matches!(v, Value::Str(_) | Value::Bool(_))),
97            None => false,
98        };
99
100        let is_datetime = match values {
101            Some(vals) => vals.iter().any(|v| v.is_datetime()),
102            None => false,
103        };
104
105        match aes {
106            Aesthetic::Color | Aesthetic::Fill => {
107                if is_discrete {
108                    let scale = ScaleColorDiscrete::new(aes.clone());
109                    self.scales.push(Box::new(scale));
110                } else {
111                    let scale = ScaleColorContinuous::new(aes.clone());
112                    self.scales.push(Box::new(scale));
113                }
114            }
115            Aesthetic::Shape => {
116                let scale = ScaleShapeDiscrete::new();
117                self.scales.push(Box::new(scale));
118            }
119            Aesthetic::Linetype => {
120                let scale = ScaleLinetypeDiscrete::new();
121                self.scales.push(Box::new(scale));
122            }
123            Aesthetic::Size => {
124                let scale = ScaleSizeContinuous::new();
125                self.scales.push(Box::new(scale));
126            }
127            Aesthetic::Linewidth => {
128                let scale = ScaleLinewidthContinuous::new();
129                self.scales.push(Box::new(scale));
130            }
131            Aesthetic::Alpha => {
132                let scale = ScaleAlphaContinuous::new();
133                self.scales.push(Box::new(scale));
134            }
135            _ => {
136                if is_discrete {
137                    let scale = ScaleDiscrete::new().for_aesthetic(aes.clone());
138                    self.scales.push(Box::new(scale));
139                } else if is_datetime {
140                    let scale = ScaleDateTime::new().for_aesthetic(aes.clone());
141                    self.scales.push(Box::new(scale));
142                } else {
143                    let scale = ScaleContinuous::new().for_aesthetic(aes.clone());
144                    self.scales.push(Box::new(scale));
145                }
146            }
147        }
148    }
149
150    /// Train all scales on data from one layer.
151    pub fn train_layer(&mut self, data: &DataFrame) {
152        for scale in &mut self.scales {
153            let col_name = scale.aesthetic().col_name().to_string();
154            if let Some(values) = data.column(&col_name) {
155                scale.train(values);
156            }
157        }
158    }
159
160    /// Map a single value through the appropriate scale.
161    pub fn map_value(&self, aes: &Aesthetic, value: &Value) -> f64 {
162        self.get(aes).map(|s| s.map(value)).unwrap_or(0.0)
163    }
164
165    /// Map a value to an RGB color through the appropriate color/fill scale.
166    pub fn map_color(&self, aes: &Aesthetic, value: &Value) -> Option<(u8, u8, u8)> {
167        self.get(aes).and_then(|s| s.map_to_color(value))
168    }
169
170    /// The `aes` scale's configured na-pattern, if any (`ScaleFillBinned::
171    /// na_pattern`, #206) — a geom checks this for a row/key it would
172    /// otherwise draw with the scale's flat na colour, before falling
173    /// back to [`map_color`](Self::map_color)'s plain result.
174    pub fn na_fill_pattern(&self, aes: &Aesthetic) -> Option<crate::render::backend::FillPattern> {
175        self.get(aes).and_then(|s| s.na_fill_pattern())
176    }
177
178    /// Map a value to a point shape through the shape scale.
179    pub fn map_shape(&self, value: &Value) -> Option<PointShape> {
180        self.get(&Aesthetic::Shape)
181            .and_then(|s| s.map_to_shape(value))
182    }
183
184    /// Map a value to a linetype through the linetype scale.
185    pub fn map_linetype(&self, value: &Value) -> Option<Linetype> {
186        self.get(&Aesthetic::Linetype)
187            .and_then(|s| s.map_to_linetype(value))
188    }
189
190    /// Map a value to a point size through the size scale.
191    pub fn map_size(&self, value: &Value) -> Option<f64> {
192        self.get(&Aesthetic::Size)
193            .and_then(|s| s.map_to_size(value))
194    }
195
196    /// Map a value to an alpha (opacity) through the alpha scale.
197    pub fn map_alpha(&self, value: &Value) -> Option<f64> {
198        self.get(&Aesthetic::Alpha)
199            .and_then(|s| s.map_to_alpha(value))
200    }
201
202    /// Map a value to a stroke width through the linewidth scale.
203    pub fn map_linewidth(&self, value: &Value) -> Option<f64> {
204        self.get(&Aesthetic::Linewidth)
205            .and_then(|s| s.map_to_size(value))
206    }
207
208    /// Override the domain limits for a scale (used by coord_cartesian zoom).
209    pub fn set_limits(&mut self, aes: &Aesthetic, min: f64, max: f64) {
210        if let Some(scale) = self.get_mut(aes) {
211            scale.set_limits(min, max);
212        }
213    }
214
215    /// Get the secondary axis for an aesthetic, if one exists.
216    pub fn sec_axis(&self, aes: &Aesthetic) -> Option<&crate::scale::sec_axis::SecAxis> {
217        self.get(aes).and_then(|s| s.sec_axis())
218    }
219
220    /// Get all scales.
221    pub fn iter(&self) -> impl Iterator<Item = &dyn Scale> {
222        self.scales.iter().map(|s| s.as_ref())
223    }
224}
225
226impl Clone for ScaleSet {
227    fn clone(&self) -> Self {
228        ScaleSet {
229            scales: self.scales.iter().map(|s| s.clone_box()).collect(),
230        }
231    }
232}
233
234impl Default for ScaleSet {
235    fn default() -> Self {
236        Self::new()
237    }
238}
ggplot_rs/scale/scale_set.rs

ggplot_rs/scale/
scale_set.rs
