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* Build: line tables only in dev, no debug info for dependencies * Tests: one integration-test binary per crate Each crate's tests/*.rs becomes a module of tests/it/main.rs. Files that install process-wide state (the file io hooks, user aliases, SAVETIME and SAVEFILEPATH, user linetype and pattern files, registered fonts) stay their own test binaries. * xtask ci: nextest, tests without examples, one wasm check call
88 lines
3.4 KiB
Rust
88 lines
3.4 KiB
Rust
//! A model-space PNG plot with `fit: false` and no `scale` plots at 1:1, as PDF does (issue #713).
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use cadcraft_doc::{Common, Drawing, EntityKind, Line, Space};
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use cadcraft_geom::Vec3;
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use serde_json::{Value, json};
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/// The RGBA rows of an 8-bit RGBA PNG (the only kind the plotter writes).
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fn decode_rgba(png: &[u8]) -> (usize, Vec<Vec<u8>>) {
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let be = |i: usize| u32::from_be_bytes([png[i], png[i + 1], png[i + 2], png[i + 3]]) as usize;
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let (w, h) = (be(16), be(20));
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assert_eq!((png[24], png[25]), (8, 6), "8-bit RGBA");
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let mut idat = Vec::new();
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let mut at = 8;
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while at + 8 <= png.len() {
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let len = be(at);
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if &png[at + 4..at + 8] == b"IDAT" {
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idat.extend_from_slice(&png[at + 8..at + 8 + len]);
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}
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at += 12 + len;
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}
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let raw = miniz_oxide::inflate::decompress_to_vec_zlib(&idat).unwrap();
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let stride = w * 4;
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let mut rows: Vec<Vec<u8>> = Vec::with_capacity(h);
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for y in 0..h {
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let line = &raw[y * (stride + 1)..(y + 1) * (stride + 1)];
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let prev = if y > 0 { rows[y - 1].clone() } else { vec![0; stride] };
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let mut cur = line[1..].to_vec();
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for i in 0..stride {
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let a = if i >= 4 { i32::from(cur[i - 4]) } else { 0 };
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let b = i32::from(prev[i]);
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let c = if i >= 4 { i32::from(prev[i - 4]) } else { 0 };
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let add = match line[0] {
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0 => 0,
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1 => a,
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2 => b,
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3 => (a + b) / 2,
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4 => {
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let p = a + b - c;
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let (pa, pb, pc) = ((p - a).abs(), (p - b).abs(), (p - c).abs());
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if pa <= pb && pa <= pc {
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a
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} else if pb <= pc {
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b
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} else {
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c
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}
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}
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f => panic!("PNG filter {f}"),
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};
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cur[i] = cur[i].wrapping_add(add as u8);
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}
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rows.push(cur);
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}
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(w, rows)
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}
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/// Plotted length in millimetres of a 100-unit horizontal line in model space, on an A4
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/// landscape PNG at 100 dpi with 5 mm margins (printable area 287 × 200 mm).
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fn plotted_mm(opts: Value) -> f64 {
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let mut d = Drawing::new_metric();
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let line = EntityKind::Line(Line { a: Vec3::ZERO, b: Vec3::new(100.0, 0.0, 0.0) });
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d.add(&Space::Model, Common::default(), line).unwrap();
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let mut o =
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json!({"output": "png", "width": 210, "height": 297, "landscape": true, "margins": [5, 5, 5, 5], "resolution": 100, "lineweights": false});
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if let (Some(o), Some(e)) = (o.as_object_mut(), opts.as_object()) {
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o.extend(e.clone());
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}
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let (w, rows) = decode_rgba(&cadcraft_io::plotter::plot(&d, &Space::Model, &o).unwrap());
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let inked: Vec<usize> = (0..w).filter(|x| rows.iter().any(|r| r[x * 4] < 128)).collect();
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let (first, last) = (inked.first().unwrap(), inked.last().unwrap());
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(last - first) as f64 * 25.4 / 100.0
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}
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#[test]
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fn model_png_without_fit_or_scale_plots_one_to_one() {
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// One pixel is 0.254 mm at 100 dpi.
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for (opts, mm) in [
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(json!({"fit": false}), 100.0),
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(json!({"fit": false, "scale": 1}), 100.0),
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(json!({"fit": false, "scale": 0.5}), 50.0),
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(json!({"fit": true}), 287.0),
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(json!({}), 287.0),
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] {
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let got = plotted_mm(opts.clone());
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assert!((got - mm).abs() < 0.6, "{opts}: {got} mm, want {mm}");
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}
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}
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