diff --git a/crates/render/src/chart.rs b/crates/render/src/chart.rs index 53794987a..8c71f7332 100644 --- a/crates/render/src/chart.rs +++ b/crates/render/src/chart.rs @@ -250,7 +250,19 @@ fn axis_ticks((lo, hi, st): (f64, f64, f64)) -> impl Iterator { (0..=n).map(move |k| lo + k as f64 * st) } +/// Most category-by-series cells one chart draws; ordinary charts hold a few hundred. +const MAX_CHART_CELLS: usize = 4_000_000; + +/// Whether the independent category and series lists make the drawing loops multiply past the budget. +fn over_cell_budget(c: &Chart) -> bool { + let ncat = c.categories.len().max(c.series.iter().map(|s| s.values.len()).max().unwrap_or(0)); + ncat.saturating_mul(c.series.len().max(1)) > MAX_CHART_CELLS +} + pub fn draw(ctx: &mut RenderContext, rctx: &Ctx, c: &Chart, m: Affine, w: f64, h: f64) { + if over_cell_budget(c) { + return; + } match c.kind { // Histograms and Pareto charts are drawn as the column (and line) chart of their bins. ChartType::Histogram | ChartType::Pareto => { @@ -1425,6 +1437,14 @@ mod tests { const AREA: Rect = Rect::new(0.0, 0.0, 400.0, 300.0); + #[test] + fn category_by_series_cells_are_budgeted() { + let mut c = Chart::sample(ChartType::Column); + assert!(!over_cell_budget(&c)); + c.categories = vec![String::new(); MAX_CHART_CELLS / c.series.len() + 1]; + assert!(over_cell_budget(&c)); + } + #[test] fn tiny_data_gets_several_ticks() { let sc = deckcraft_model::chart::axis_scale(1e-13, 5e-13, None, None, None, 8, true);