charton 0.5.0

A high-performance, layered charting system for Rust, featuring a flexible data core and multi-backend rendering.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60

use crate::coordinate::Rect;
use crate::facets::{Facet, FacetCell, FacetInfo, FacetLayout, FacetStrategy};
use crate::theme::Theme;

/// FacetGrid partitions data by two variables into a strict Row x Column matrix.
pub struct FacetGrid {
    pub row_field: String,
    pub col_field: String,
    pub strategy: FacetStrategy,
}

impl Facet for FacetGrid {
    fn fields(&self) -> Vec<String> {
        vec![self.row_field.clone(), self.col_field.clone()]
    }
    fn strategy(&self) -> FacetStrategy {
        self.strategy
    }

    fn compute_layout(
        &self,
        factors: &[Vec<String>],
        container: &Rect,
        theme: &Theme,
    ) -> FacetLayout {
        let rows_vals = &factors[0];
        let cols_vals = &factors[1];

        let n_rows = rows_vals.len();
        let n_cols = cols_vals.len();

        let header_h = theme.facet_label_size * 1.5;
        let gap = theme.facet_spacing;

        let panel_w = (container.width - (n_cols - 1) as f64 * gap) / n_cols as f64;
        let panel_h = (container.height - (n_rows - 1) as f64 * gap - n_rows as f64 * header_h)
            / n_rows as f64;

        let mut cells = Vec::new();
        for (r_idx, r_val) in rows_vals.iter().enumerate() {
            for (c_idx, c_val) in cols_vals.iter().enumerate() {
                let x = container.x + c_idx as f64 * (panel_w + gap);
                let header_y = container.y + r_idx as f64 * (panel_h + header_h + gap);

                cells.push(FacetCell {
                    rect: Rect::new(x, header_y + header_h, panel_w, panel_h),
                    header_rect: Rect::new(x, header_y, panel_w, header_h),
                    info: FacetInfo {
                        row: r_idx,
                        col: c_idx,
                        total_rows: n_rows,
                        total_cols: n_cols,
                        label: format!("{} | {}", r_val, c_val), // Combined label for now
                    },
                });
            }
        }
        FacetLayout { cells }
    }
}