vello_bench/src/flatten.rs

// Copyright 2025 the Vello Authors
// SPDX-License-Identifier: Apache-2.0 OR MIT

use crate::data::get_data_items;
use criterion::Criterion;
use vello_common::flatten;
use vello_common::flatten::FlattenCtx;
use vello_common::geometry::RectU16;
use vello_common::kurbo::Stroke;
use vello_common::kurbo::StrokeCtx;
use vello_cpu::Level;
use vello_cpu::kurbo::Affine;

pub fn flatten(c: &mut Criterion) {
    let mut g = c.benchmark_group("flatten");

    macro_rules! flatten_single {
        ($item:expr) => {
            let expanded_strokes = $item.expanded_strokes();

            g.bench_function($item.name.clone(), |b| {
                // Reuse allocations to better simulate real-world use.
                let mut line_buf: Vec<flatten::Line> = vec![];
                let mut temp_buf: Vec<flatten::Line> = vec![];
                let mut flatten_ctx = FlattenCtx::default();

                b.iter(|| {
                    line_buf.clear();

                    for path in &$item.fills {
                        flatten::fill(
                            Level::new(),
                            &path.path,
                            path.transform,
                            &mut temp_buf,
                            &mut flatten_ctx,
                            RectU16::new(0, 0, $item.width, $item.height),
                        );
                        line_buf.extend(&temp_buf);
                    }

                    for stroke in &expanded_strokes {
                        flatten::fill(
                            Level::new(),
                            stroke,
                            Affine::IDENTITY,
                            &mut temp_buf,
                            &mut flatten_ctx,
                            RectU16::new(0, 0, $item.width, $item.height),
                        );
                        line_buf.extend(&temp_buf);
                    }

                    std::hint::black_box(&line_buf);
                })
            });
        };
    }

    for item in get_data_items() {
        flatten_single!(item);
    }
}

pub fn strokes(c: &mut Criterion) {
    let mut g = c.benchmark_group("strokes");

    macro_rules! expand_single {
        ($item:expr) => {
            g.bench_function($item.name.clone(), |b| {
                let mut stroke_ctx = StrokeCtx::default();

                b.iter(|| {
                    let mut paths = vec![];

                    for path in &$item.strokes {
                        let stroke = Stroke {
                            width: path.stroke_width as f64,
                            ..Default::default()
                        };
                        flatten::expand_stroke(path.path.iter(), &stroke, 0.25, &mut stroke_ctx);
                        paths.push(stroke_ctx.output().clone());
                    }

                    std::hint::black_box(&paths);
                })
            });
        };
    }

    for item in get_data_items() {
        expand_single!(item);
    }
}