NOWN-DEV
764fcaa5a8
sheet.export_dxf writes an AutoCAD 2000 drawing with ELLIPSE and SPLINE entities for ellipses, splines and text outlines instead of chords, with curves: arcs for machines that read only lines and arcs. Perforation circles go through the same writer. Closes #1089.
671 lines
30 KiB
Rust
671 lines
30 KiB
Rust
//! The flat pattern's DXF drawing, as AutoCAD 2000 (`AC1015`), the oldest release that has the
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//! ELLIPSE and SPLINE entities.
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//!
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//! Curves stay exact: a circle is a CIRCLE, a circular arc an ARC, a whole ellipse one ELLIPSE
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//! and a conic arc of weight below 1 an elliptical ELLIPSE arc; Béziers (TrueType glyph
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//! outlines, spline pieces) and the other conics are SPLINEs of their own degree. The file holds
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//! what the entities refer to and what release 2000 needs to read them: the version, the
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//! handle seed, the units and the extents; the linetype, layer and block-record tables; the
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//! model and paper space blocks; handles, owners and the subclass markers of each entity; the
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//! root dictionary. Group codes follow Autodesk's public DXF reference.
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use std::f64::consts::TAU;
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use std::fmt::Write as _;
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use solidcraft_geom::{Loop2, Seg2, Vec2};
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/// A layer: its name and AutoCAD colour index (1 red, 3 green, 5 blue, 7 white or black).
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#[derive(Clone, Debug, PartialEq)]
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pub struct DxfLayer {
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pub name: String,
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pub color: i16,
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}
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/// The geometry of one entity (millimetres).
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#[derive(Clone, Debug, PartialEq)]
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pub enum DxfShape {
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Line(Vec2, Vec2),
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Circle {
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c: Vec2,
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r: f64,
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},
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/// Counter-clockwise from `a0` to `a1` (degrees).
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Arc {
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c: Vec2,
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r: f64,
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a0: f64,
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a1: f64,
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},
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/// An ellipse or an arc of one, counter-clockwise from parameter `t0` to `t1` (radians):
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/// the point at `t` is `c + major·cos t + perp(major)·ratio·sin t`, `major` being the
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/// vector from the centre to the end of the major axis and `ratio` the minor radius over
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/// the major one (0 < ratio ≤ 1). A whole ellipse runs from 0 to 2π.
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Ellipse {
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c: Vec2,
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major: Vec2,
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ratio: f64,
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t0: f64,
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t1: f64,
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},
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/// A clamped B-spline of `degree` over `ctrl`, rational when `weights` are given.
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Spline {
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degree: u8,
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knots: Vec<f64>,
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ctrl: Vec<Vec2>,
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weights: Option<Vec<f64>>,
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},
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}
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/// An entity on a layer.
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#[derive(Clone, Debug, PartialEq)]
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pub struct DxfEntity {
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pub layer: String,
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pub shape: DxfShape,
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}
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/// The entity of one profile segment, exactly: a line, an arc (a circle when it is a whole
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/// turn), an elliptical arc for a conic of weight below 1, a spline for a Bézier or any other conic.
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pub fn seg_shape(s: &Seg2) -> DxfShape {
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match *s {
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Seg2::Line { a, b } => DxfShape::Line(a, b),
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Seg2::Arc { center, radius, start, sweep } => {
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if (sweep.abs() - TAU).abs() < 1e-9 {
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return DxfShape::Circle { c: center, r: radius };
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}
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let (a0, a1) = if sweep >= 0.0 { (start, start + sweep) } else { (start + sweep, start) };
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DxfShape::Arc { c: center, r: radius, a0: a0.to_degrees().rem_euclid(360.0), a1: a1.to_degrees().rem_euclid(360.0) }
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}
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Seg2::Conic { a, apex, b, w } => match conic_ellipse(a, apex, b, w) {
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Some(e) => DxfShape::Ellipse { c: e.c, major: e.major, ratio: e.ratio, t0: wrap(e.t0), t1: wrap(e.t1) },
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None => bezier_spline(&[a, apex, b], ((w - 1.0).abs() > 1e-12).then(|| vec![1.0, w, 1.0])),
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},
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Seg2::Cubic { p0, p1, p2, p3 } => bezier_spline(&[p0, p1, p2, p3], None),
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Seg2::Bezier { n, p } => bezier_spline(p.get(..=(n as usize).clamp(1, 7)).unwrap_or(&p), None),
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}
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}
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/// The entities of a closed loop: one ELLIPSE when it is a whole ellipse of conic arcs, else
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/// one entity for each segment.
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pub fn loop_shapes(lp: &Loop2) -> Vec<DxfShape> {
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let arcs: Option<Vec<EllipseArc>> =
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lp.segs.iter().map(|s| if let Seg2::Conic { a, apex, b, w } = *s { conic_ellipse(a, apex, b, w) } else { None }).collect();
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if let Some(arcs) = arcs
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&& let Some(first) = arcs.first()
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&& arcs.iter().all(|e| e.same_ellipse(first))
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&& (arcs.iter().map(|e| e.t1 - e.t0).sum::<f64>() - TAU).abs() < 1e-7
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{
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return vec![DxfShape::Ellipse { c: first.c, major: first.major, ratio: first.ratio, t0: 0.0, t1: TAU }];
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}
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lp.segs.iter().map(seg_shape).collect()
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}
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/// A parameter reduced to [0, 2π); one within 1e-12 of a full turn is 0.
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fn wrap(t: f64) -> f64 {
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let r = t.rem_euclid(TAU);
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if r > TAU - 1e-12 { 0.0 } else { r }
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}
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/// An elliptical arc as DXF describes it (the parameters are not yet reduced to 0…2π).
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#[derive(Clone, Copy, Debug)]
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struct EllipseArc {
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c: Vec2,
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major: Vec2,
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ratio: f64,
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t0: f64,
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t1: f64,
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}
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impl EllipseArc {
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fn same_ellipse(&self, o: &EllipseArc) -> bool {
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let tol = 1e-7 * self.major.len().max(1.0);
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let parallel = self.major.cross(o.major).abs() <= tol * self.major.len();
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self.c.dist(o.c) <= tol && parallel && (self.major.len() - o.major.len()).abs() <= tol && (self.ratio - o.ratio).abs() <= 1e-9
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}
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}
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/// The ellipse a rational quadratic Bézier of weight `w` below 1 (end weights 1) lies on. The
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/// arc is `c + u·cos θ + v·sin θ` for θ from −α to α, `cos α = w`, with the conjugate
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/// semi-diameters `u` (from the centre towards the arc's middle) and `v` (towards its end).
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/// With `m` the middle of the chord, `apex − m = u·(1 − w²)/w` and `m − c = w·u`, so
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/// `c = m − (apex − m)·w²/(1 − w²)`, and `v = (b − m)/sin α`. The principal axes are where
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/// |u cos t + v sin t| is largest and smallest, tan 2t = 2 u·v / (u² − v²).
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fn conic_ellipse(a: Vec2, apex: Vec2, b: Vec2, w: f64) -> Option<EllipseArc> {
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// Within 1e-6 of 1 the centre is hundreds of metres away: a rational spline is exact too.
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if !(w > 1e-9 && w < 1.0 - 1e-6) {
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return None;
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}
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let m = (a + b) * 0.5;
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let c = m - (apex - m) * (w * w / (1.0 - w * w));
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let alpha = w.acos();
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let (u, v) = ((m - c) / w, (b - m) / alpha.sin());
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if !(c.is_finite() && u.is_finite() && v.is_finite()) || u.cross(v).abs() < 1e-18 {
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return None;
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}
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let t = 0.5 * (2.0 * u.dot(v)).atan2(u.dot(u) - v.dot(v));
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let major = u * t.cos() + v * t.sin();
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let minor = v * t.cos() - u * t.sin();
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if !(major.len() > 1e-12) {
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return None;
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}
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let ratio = (minor.len() / major.len()).clamp(1e-12, 1.0);
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// DXF runs counter-clockwise with the minor axis a quarter turn ahead of the major one. If
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// `minor` lies on the other side the arc, which runs a → b with increasing θ, is clockwise.
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let (t0, t1) = if major.cross(minor) > 0.0 { (-alpha - t, alpha - t) } else { (t - alpha, t + alpha) };
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Some(EllipseArc { c, major, ratio, t0, t1 })
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}
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/// A Bézier over `pts` (weights `weights`) as a clamped spline of degree `pts.len() − 1`.
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fn bezier_spline(pts: &[Vec2], weights: Option<Vec<f64>>) -> DxfShape {
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let degree = pts.len().saturating_sub(1).max(1);
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let knots = std::iter::repeat_n(0.0, degree + 1).chain(std::iter::repeat_n(1.0, degree + 1)).collect();
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DxfShape::Spline { degree: degree as u8, knots, ctrl: pts.to_vec(), weights }
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}
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impl DxfShape {
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/// Points on the shape (or its control polygon) for the drawing's extents.
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fn sample(&self, out: &mut Vec<Vec2>) {
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match self {
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DxfShape::Line(a, b) => out.extend([*a, *b]),
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DxfShape::Circle { c, r } => out.extend([*c - Vec2::new(*r, *r), *c + Vec2::new(*r, *r)]),
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DxfShape::Arc { c, r, a0, a1 } => {
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let sweep = (a1 - a0).rem_euclid(360.0);
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out.extend((0..=64).map(|i| *c + Vec2::from_angle((a0 + sweep * i as f64 / 64.0).to_radians()) * *r));
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}
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DxfShape::Ellipse { c, major, ratio, t0, t1 } => {
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let (minor, sweep) = (major.perp() * *ratio, if (t1 - t0 - TAU).abs() < 1e-12 { TAU } else { (t1 - t0).rem_euclid(TAU) });
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out.extend((0..=128).map(|i| {
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let t = t0 + sweep * i as f64 / 128.0;
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*c + *major * t.cos() + minor * t.sin()
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}));
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}
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// A spline lies within the hull of its control points.
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DxfShape::Spline { ctrl, .. } => out.extend(ctrl.iter().copied()),
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}
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}
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}
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/// Group codes and handles, in file order.
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struct Out {
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s: String,
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next: u64,
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}
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impl Out {
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fn code(&mut self, c: i32, v: impl std::fmt::Display) {
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let _ = write!(self.s, "{c:>3}\n{v}\n");
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}
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/// A real number: up to twelve decimals, at least one.
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fn num(&mut self, c: i32, v: f64) {
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let text = format!("{:.12}", if v.is_finite() { v } else { 0.0 });
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let text = text.trim_end_matches('0');
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let text = if text.ends_with('.') { format!("{text}0") } else { text.to_string() };
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self.code(c, if text == "-0.0" { "0.0" } else { text.as_str() });
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}
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/// A point in the plane at height 0: codes `c`, `c + 10`, `c + 20`.
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fn point(&mut self, c: i32, p: Vec2) {
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self.num(c, p.x);
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self.num(c + 10, p.y);
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self.num(c + 20, 0.0);
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}
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fn handle(&mut self) -> String {
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let h = format!("{:X}", self.next);
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self.next += 1;
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h
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}
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/// The start of a symbol table; returns its handle.
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fn table(&mut self, name: &str, entries: usize) -> String {
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let h = self.handle();
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self.code(0, "TABLE");
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self.code(2, name);
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self.code(5, &h);
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self.code(330, 0);
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self.code(100, "AcDbSymbolTable");
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self.code(70, entries);
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h
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}
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/// The start of a symbol table record.
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fn record(&mut self, kind: &str, subclass: &str, table: &str) {
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let h = self.handle();
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self.code(0, kind);
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self.code(5, h);
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self.code(330, table);
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self.code(100, "AcDbSymbolTableRecord");
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self.code(100, subclass);
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}
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/// A BLOCK and its ENDBLK, empty, owned by the block record `owner`.
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fn block(&mut self, owner: &str, name: &str, paper: bool) {
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for (kind, sub) in [("BLOCK", "AcDbBlockBegin"), ("ENDBLK", "AcDbBlockEnd")] {
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let h = self.handle();
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self.code(0, kind);
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self.code(5, h);
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self.code(330, owner);
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self.code(100, "AcDbEntity");
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if paper {
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self.code(67, 1);
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}
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self.code(8, "0");
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self.code(100, sub);
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if kind == "BLOCK" {
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self.code(2, name);
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self.code(70, 0);
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self.point(10, Vec2::ZERO);
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self.code(3, name);
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self.code(1, "");
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}
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}
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}
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}
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/// A DXF drawing (AutoCAD 2000, millimetres) of `entities`. `layers` are the layers they are on
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/// (layer `0` is always there).
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pub fn write_dxf_drawing(layers: &[DxfLayer], entities: &[DxfEntity]) -> String {
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let mut pts = Vec::new();
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for e in entities {
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e.shape.sample(&mut pts);
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}
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pts.retain(|p| p.is_finite());
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let (lo, hi) = pts
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.iter()
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.fold(None, |acc: Option<(Vec2, Vec2)>, p| {
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Some(acc.map_or((*p, *p), |(lo, hi)| (Vec2::new(lo.x.min(p.x), lo.y.min(p.y)), Vec2::new(hi.x.max(p.x), hi.y.max(p.y)))))
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})
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.unwrap_or((Vec2::ZERO, Vec2::ZERO));
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let mut layer_list = vec![DxfLayer { name: "0".into(), color: 7 }];
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for l in layers {
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if !layer_list.iter().any(|x| x.name == l.name) {
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layer_list.push(l.clone());
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}
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}
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// Everything but the header, which needs the handle seed.
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let mut o = Out { s: String::new(), next: 0x20 };
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let (model, paper) = (o.handle(), o.handle());
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let root = o.handle();
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o.code(0, "SECTION");
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o.code(2, "TABLES");
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let t = o.table("LTYPE", 3);
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for (name, description) in [("ByBlock", ""), ("ByLayer", ""), ("Continuous", "Solid line")] {
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o.record("LTYPE", "AcDbLinetypeTableRecord", &t);
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o.code(2, name);
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o.code(70, 0);
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o.code(3, description);
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o.code(72, 65);
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o.code(73, 0);
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o.num(40, 0.0);
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}
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o.code(0, "ENDTAB");
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let t = o.table("LAYER", layer_list.len());
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for l in &layer_list {
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o.record("LAYER", "AcDbLayerTableRecord", &t);
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o.code(2, &l.name);
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o.code(70, 0);
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o.code(62, l.color);
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o.code(6, "Continuous");
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}
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o.code(0, "ENDTAB");
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let t = o.table("BLOCK_RECORD", 2);
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for (h, name) in [(&model, "*Model_Space"), (&paper, "*Paper_Space")] {
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o.code(0, "BLOCK_RECORD");
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o.code(5, h);
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o.code(330, &t);
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o.code(100, "AcDbSymbolTableRecord");
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o.code(100, "AcDbBlockTableRecord");
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o.code(2, name);
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}
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o.code(0, "ENDTAB");
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o.code(0, "ENDSEC");
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o.code(0, "SECTION");
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o.code(2, "BLOCKS");
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o.block(&model, "*Model_Space", false);
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o.block(&paper, "*Paper_Space", true);
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o.code(0, "ENDSEC");
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o.code(0, "SECTION");
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o.code(2, "ENTITIES");
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for e in entities {
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let kind = match &e.shape {
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DxfShape::Line(..) => "LINE",
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DxfShape::Circle { .. } => "CIRCLE",
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DxfShape::Arc { .. } => "ARC",
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DxfShape::Ellipse { .. } => "ELLIPSE",
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DxfShape::Spline { .. } => "SPLINE",
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};
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let h = o.handle();
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o.code(0, kind);
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o.code(5, h);
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o.code(330, &model);
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o.code(100, "AcDbEntity");
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o.code(8, if e.layer.trim().is_empty() { "0" } else { e.layer.as_str() });
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match &e.shape {
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DxfShape::Line(a, b) => {
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o.code(100, "AcDbLine");
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o.point(10, *a);
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o.point(11, *b);
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}
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DxfShape::Circle { c, r } => {
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o.code(100, "AcDbCircle");
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o.point(10, *c);
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o.num(40, *r);
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}
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DxfShape::Arc { c, r, a0, a1 } => {
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o.code(100, "AcDbCircle");
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o.point(10, *c);
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o.num(40, *r);
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o.code(100, "AcDbArc");
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o.num(50, *a0);
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o.num(51, *a1);
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}
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DxfShape::Ellipse { c, major, ratio, t0, t1 } => {
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o.code(100, "AcDbEllipse");
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o.point(10, *c);
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o.point(11, *major);
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o.num(210, 0.0);
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o.num(220, 0.0);
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o.num(230, 1.0);
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o.num(40, *ratio);
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o.num(41, *t0);
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o.num(42, *t1);
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}
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DxfShape::Spline { degree, knots, ctrl, weights } => {
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o.code(100, "AcDbSpline");
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o.num(210, 0.0);
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o.num(220, 0.0);
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o.num(230, 1.0);
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// Flags: 4 rational, 8 planar.
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o.code(70, 8 + if weights.is_some() { 4 } else { 0 });
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o.code(71, degree);
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o.code(72, knots.len());
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o.code(73, ctrl.len());
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o.code(74, 0);
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// Knots, then weights, then control points: the order of the reference.
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for k in knots {
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o.num(40, *k);
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}
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for w in weights.iter().flatten() {
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o.num(41, *w);
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}
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for p in ctrl {
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o.point(10, *p);
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}
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}
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}
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}
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o.code(0, "ENDSEC");
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o.code(0, "SECTION");
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o.code(2, "OBJECTS");
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o.code(0, "DICTIONARY");
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o.code(5, root.as_str());
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o.code(330, 0);
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o.code(100, "AcDbDictionary");
|
||
o.code(281, 1);
|
||
o.code(0, "ENDSEC");
|
||
o.code(0, "EOF");
|
||
|
||
let mut head = Out { s: String::new(), next: 0 };
|
||
head.code(0, "SECTION");
|
||
head.code(2, "HEADER");
|
||
head.code(9, "$ACADVER");
|
||
head.code(1, "AC1015");
|
||
head.code(9, "$HANDSEED");
|
||
head.code(5, format!("{:X}", o.next));
|
||
head.code(9, "$INSUNITS");
|
||
head.code(70, 4);
|
||
head.code(9, "$MEASUREMENT");
|
||
head.code(70, 1);
|
||
head.code(9, "$EXTMIN");
|
||
head.point(10, lo);
|
||
head.code(9, "$EXTMAX");
|
||
head.point(10, hi);
|
||
head.code(0, "ENDSEC");
|
||
head.s + &o.s
|
||
}
|
||
|
||
#[cfg(test)]
|
||
mod tests {
|
||
use std::f64::consts::{FRAC_1_SQRT_2, FRAC_PI_2, PI};
|
||
|
||
use super::*;
|
||
use crate::{Geom2, read_dxf};
|
||
|
||
/// The conic quarter of the ellipse `c ± u`, `c ± v` from `c + u` to `c + v`.
|
||
fn quarter(c: Vec2, u: Vec2, v: Vec2) -> Seg2 {
|
||
Seg2::Conic { a: c + u, apex: c + u + v, b: c + v, w: FRAC_1_SQRT_2 }
|
||
}
|
||
|
||
/// The ellipse of 50 × 24 round (50, 40): its four quarters, counter-clockwise from (75, 40).
|
||
fn oval() -> [Seg2; 4] {
|
||
let (c, u, v) = (Vec2::new(50.0, 40.0), Vec2::new(25.0, 0.0), Vec2::new(0.0, 12.0));
|
||
[quarter(c, u, v), quarter(c, v, -u), quarter(c, -u, -v), quarter(c, -v, u)]
|
||
}
|
||
|
||
fn ellipse_point(e: &DxfShape, t: f64) -> Vec2 {
|
||
let DxfShape::Ellipse { c, major, ratio, .. } = e else { panic!("{e:?}") };
|
||
*c + *major * t.cos() + major.perp() * (*ratio * t.sin())
|
||
}
|
||
|
||
/// A DXF text as (group code, value) pairs.
|
||
fn pairs(dxf: &str) -> Vec<(i32, String)> {
|
||
let lines: Vec<&str> = dxf.lines().collect();
|
||
lines.chunks(2).map(|c| (c[0].trim().parse().unwrap(), c.get(1).unwrap_or(&"").trim().to_string())).collect()
|
||
}
|
||
|
||
/// The entities of the ENTITIES section: their type and group codes.
|
||
fn entities(dxf: &str) -> Vec<(String, Vec<(i32, String)>)> {
|
||
let p = pairs(dxf);
|
||
let start = p.iter().position(|(c, v)| (*c, v.as_str()) == (2, "ENTITIES")).unwrap();
|
||
let mut out: Vec<(String, Vec<(i32, String)>)> = Vec::new();
|
||
for (c, v) in &p[start + 1..] {
|
||
match (*c, v.as_str()) {
|
||
(0, "ENDSEC") => break,
|
||
(0, kind) => out.push((kind.to_string(), Vec::new())),
|
||
_ => out.last_mut().unwrap().1.push((*c, v.clone())),
|
||
}
|
||
}
|
||
out
|
||
}
|
||
|
||
fn values(e: &(String, Vec<(i32, String)>), code: i32) -> Vec<f64> {
|
||
e.1.iter().filter(|(c, _)| *c == code).map(|(_, v)| v.parse().unwrap()).collect()
|
||
}
|
||
|
||
fn near(a: &[f64], b: &[f64]) -> bool {
|
||
a.len() == b.len() && a.iter().zip(b).all(|(x, y)| (x - y).abs() < 1e-9)
|
||
}
|
||
|
||
#[test]
|
||
fn a_conic_arc_below_weight_one_is_an_elliptical_arc() {
|
||
// By hand: the first quarter of the 25 × 12 ellipse round (50, 40) runs from (75, 40)
|
||
// over the corner (75, 52) to (50, 52) with weight cos 45°. Its centre is
|
||
// m − (apex − m)·w²/(1 − w²) = (62.5, 46) − (12.5, 6)·1 = (50, 40); the semi-diameters
|
||
// u = (m − c)/w and v = (b − m)/sin 45° are (25, 12) and (−25, 12) over √2, which are
|
||
// equally long, so the principal axes are 45° from them: the major one is
|
||
// (u − v)/√2 = (25, 0), the minor one (u + v)/√2 = (0, 12), the ratio 12/25 and, from
|
||
// (75, 40) to (50, 52), the parameters 0 to π/2.
|
||
let [first, second, ..] = oval();
|
||
let DxfShape::Ellipse { c, major, ratio, t0, t1 } = seg_shape(&first) else { panic!("{:?}", seg_shape(&first)) };
|
||
assert!(c.dist(Vec2::new(50.0, 40.0)) < 1e-9 && major.dist(Vec2::new(25.0, 0.0)) < 1e-9, "{c:?} {major:?}");
|
||
assert!((ratio - 0.48).abs() < 1e-12 && t0.abs() < 1e-9 && (t1 - FRAC_PI_2).abs() < 1e-9, "{ratio} {t0} {t1}");
|
||
// Whatever axis the second quarter is described by, its arc starts and ends at the
|
||
// segment's ends and every point of it lies on the segment.
|
||
let tilt = |v: Vec2| Vec2::from_angle(0.3) * v.x + Vec2::from_angle(0.3).perp() * v.y;
|
||
let (centre, u, v) = (Vec2::new(5.0, -2.0), tilt(Vec2::new(15.0, 0.0)), tilt(Vec2::new(0.0, 8.0)));
|
||
let general = quarter(centre, u, v).split_at(0.3).1;
|
||
for seg in [first, second, quarter(centre, u, v), quarter(centre, v, -u).reversed(), general, general.reversed()] {
|
||
let e = seg_shape(&seg);
|
||
let DxfShape::Ellipse { t0, t1, .. } = e else { panic!("{e:?}") };
|
||
let sweep = (t1 - t0).rem_euclid(TAU);
|
||
for i in 0..=20 {
|
||
let p = ellipse_point(&e, t0 + sweep * i as f64 / 20.0);
|
||
assert!(seg.point_at(seg.closest_param(p)).dist(p) < 1e-9, "{seg:?} {p:?}");
|
||
}
|
||
let ends = [ellipse_point(&e, t0), ellipse_point(&e, t0 + sweep)];
|
||
assert!(ends.iter().any(|p| p.dist(seg.start()) < 1e-9) && ends.iter().any(|p| p.dist(seg.end()) < 1e-9), "{ends:?} {seg:?}");
|
||
}
|
||
}
|
||
|
||
#[test]
|
||
fn four_quarters_are_one_ellipse() {
|
||
let quarters = oval();
|
||
let reversed = Loop2 { segs: quarters.iter().rev().map(Seg2::reversed).collect() };
|
||
let shifted = Loop2 { segs: quarters.iter().cycle().skip(2).take(4).copied().collect() };
|
||
for lp in [Loop2 { segs: quarters.to_vec() }, reversed, shifted] {
|
||
let shapes = loop_shapes(&lp);
|
||
let [DxfShape::Ellipse { c, major, ratio, t0, t1 }] = shapes.as_slice() else { panic!("{shapes:?}") };
|
||
assert!(
|
||
c.dist(Vec2::new(50.0, 40.0)) < 1e-9 && (major.len() - 25.0).abs() < 1e-9 && major.cross(Vec2::X).abs() < 1e-9,
|
||
"{c:?} {major:?}"
|
||
);
|
||
assert!((ratio - 0.48).abs() < 1e-12 && *t0 == 0.0 && *t1 == TAU, "{ratio} {t0} {t1}");
|
||
}
|
||
// Three quarters and a line are pieces: three ELLIPSE arcs and a LINE.
|
||
let (q, line) = (oval(), Seg2::Line { a: Vec2::new(50.0, 28.0), b: Vec2::new(50.0, 28.0) + Vec2::X });
|
||
let open = loop_shapes(&Loop2 { segs: vec![q[0], q[1], q[2], line] });
|
||
assert!(matches!(open.as_slice(), [DxfShape::Ellipse { t1, .. }, _, _, DxfShape::Line(..)] if (*t1 - FRAC_PI_2).abs() < 1e-9), "{open:?}");
|
||
// A circle of arcs is the caller's business, but a whole turn is one CIRCLE.
|
||
let turn = Seg2::Arc { center: Vec2::new(3.0, 4.0), radius: 2.0, start: -PI, sweep: -TAU };
|
||
assert_eq!(seg_shape(&turn), DxfShape::Circle { c: Vec2::new(3.0, 4.0), r: 2.0 });
|
||
}
|
||
|
||
#[test]
|
||
fn beziers_and_the_other_conics_are_splines() {
|
||
let p = [Vec2::new(0.0, 0.0), Vec2::new(1.0, 2.0), Vec2::new(3.0, 3.0), Vec2::new(4.0, 0.0)];
|
||
let cubic = seg_shape(&Seg2::Cubic { p0: p[0], p1: p[1], p2: p[2], p3: p[3] });
|
||
assert_eq!(cubic, DxfShape::Spline { degree: 3, knots: vec![0.0, 0.0, 0.0, 0.0, 1.0, 1.0, 1.0, 1.0], ctrl: p.to_vec(), weights: None });
|
||
// A quadratic (a glyph curve) is a parabola: degree 2, not rational. Weight 2 is a
|
||
// hyperbola: rational. Weight 1 − 10⁻⁹ is no ellipse a reader could place: rational too.
|
||
let conic = |w: f64| seg_shape(&Seg2::Conic { a: p[0], apex: p[1], b: p[3], w });
|
||
let degree_2 = |s: &DxfShape, weights: Option<Vec<f64>>| {
|
||
*s == DxfShape::Spline { degree: 2, knots: vec![0.0, 0.0, 0.0, 1.0, 1.0, 1.0], ctrl: vec![p[0], p[1], p[3]], weights }
|
||
};
|
||
assert!(degree_2(&conic(1.0), None));
|
||
assert!(degree_2(&conic(2.0), Some(vec![1.0, 2.0, 1.0])));
|
||
assert!(degree_2(&conic(1.0 - 1e-9), Some(vec![1.0, 1.0 - 1e-9, 1.0])));
|
||
// A quintic piece: six control points and twelve knots.
|
||
let mut q = [Vec2::ZERO; 8];
|
||
for (i, s) in q.iter_mut().enumerate() {
|
||
*s = Vec2::new(i as f64, (i * i) as f64);
|
||
}
|
||
let DxfShape::Spline { degree, knots, ctrl, weights } = seg_shape(&Seg2::Bezier { n: 5, p: q }) else { panic!() };
|
||
assert_eq!((degree, knots.len(), ctrl.len(), weights), (5, 12, 6, None));
|
||
assert!(knots[..6].iter().all(|k| *k == 0.0) && knots[6..].iter().all(|k| *k == 1.0) && ctrl[5] == q[5]);
|
||
}
|
||
|
||
#[test]
|
||
fn drawings_carry_version_units_extents_and_handles() {
|
||
let ents = vec![
|
||
DxfEntity { layer: "OUTLINE".into(), shape: DxfShape::Line(Vec2::new(-1.0, 2.0), Vec2::new(10.0, 2.0)) },
|
||
DxfEntity { layer: "OUTLINE".into(), shape: DxfShape::Circle { c: Vec2::new(5.0, 5.0), r: 4.0 } },
|
||
DxfEntity { layer: "CUT".into(), shape: DxfShape::Line(Vec2::ZERO, Vec2::X) },
|
||
];
|
||
let dxf = write_dxf_drawing(&[DxfLayer { name: "OUTLINE".into(), color: 7 }, DxfLayer { name: "CUT".into(), color: 1 }], &ents);
|
||
let p = pairs(&dxf);
|
||
let after = |var: &str| &p[p.iter().position(|(c, v)| (*c, v.as_str()) == (9, var)).unwrap() + 1..];
|
||
assert_eq!(after("$ACADVER")[0], (1, "AC1015".to_string()));
|
||
assert_eq!(after("$INSUNITS")[0], (70, "4".to_string()));
|
||
// The circle reaches (1, 1) to (9, 9), the first line starts at x = −1 and the last at y = 0.
|
||
assert_eq!(&after("$EXTMIN")[..3], &[(10, "-1.0".to_string()), (20, "0.0".to_string()), (30, "0.0".to_string())]);
|
||
assert_eq!(&after("$EXTMAX")[..2], &[(10, "10.0".to_string()), (20, "9.0".to_string())]);
|
||
// Layer 0 and the two layers are in the LAYER table, each entity is on one of them,
|
||
// and the entities belong to the model space block record.
|
||
let layer_table = p.iter().position(|(c, v)| (*c, v.as_str()) == (2, "LAYER")).unwrap();
|
||
let names: Vec<&str> = p[layer_table..]
|
||
.iter()
|
||
.take_while(|(c, v)| (*c, v.as_str()) != (0, "ENDTAB"))
|
||
.filter(|(c, _)| *c == 2)
|
||
.map(|(_, v)| v.as_str())
|
||
.collect();
|
||
assert_eq!(names, ["LAYER", "0", "OUTLINE", "CUT"]);
|
||
// (The first "*Model_Space" is the BLOCK_RECORD, whose handle is four pairs before its name.)
|
||
let model_at = p.iter().position(|(c, v)| (*c, v.as_str()) == (2, "*Model_Space")).unwrap();
|
||
let model = p[model_at - 4].1.clone();
|
||
assert_eq!(p[model_at - 4].0, 5);
|
||
for e in entities(&dxf) {
|
||
assert!(e.1.contains(&(330, model.clone())) && e.1.contains(&(100, "AcDbEntity".to_string())), "{e:?}");
|
||
assert!(names.contains(&e.1.iter().find(|(c, _)| *c == 8).unwrap().1.as_str()));
|
||
}
|
||
// Handles are unique and the seed is above all of them.
|
||
let seed_at = p.iter().position(|(c, v)| (*c, v.as_str()) == (9, "$HANDSEED")).unwrap() + 1;
|
||
let handles: Vec<u64> =
|
||
p.iter().enumerate().filter(|(i, (c, _))| *i != seed_at && *c == 5).map(|(_, (_, v))| u64::from_str_radix(v, 16).unwrap()).collect();
|
||
let mut sorted = handles.clone();
|
||
sorted.sort_unstable();
|
||
sorted.dedup();
|
||
assert_eq!(sorted.len(), handles.len());
|
||
assert!(handles.len() > ents.len() && handles.iter().all(|h| *h < u64::from_str_radix(&p[seed_at].1, 16).unwrap()));
|
||
assert!(dxf.ends_with(" 0\nEOF\n"));
|
||
// No entities: a valid, empty drawing.
|
||
assert_eq!(entities(&write_dxf_drawing(&[], &[])).len(), 0);
|
||
}
|
||
|
||
#[test]
|
||
fn what_is_written_is_what_the_reader_gets_back() {
|
||
let quarter_one = seg_shape(&oval()[0]);
|
||
let cubic = [Vec2::new(0.0, 0.0), Vec2::new(5.0, 10.0), Vec2::new(15.0, 10.0), Vec2::new(20.0, 0.0)];
|
||
let shapes = vec![
|
||
DxfShape::Line(Vec2::new(0.0, 0.0), Vec2::new(10.0, 0.0)),
|
||
DxfShape::Circle { c: Vec2::new(5.0, 5.0), r: 2.0 },
|
||
DxfShape::Arc { c: Vec2::ZERO, r: 3.0, a0: 0.0, a1: 90.0 },
|
||
loop_shapes(&Loop2 { segs: oval().to_vec() }).remove(0),
|
||
quarter_one,
|
||
seg_shape(&Seg2::Cubic { p0: cubic[0], p1: cubic[1], p2: cubic[2], p3: cubic[3] }),
|
||
];
|
||
let ents: Vec<DxfEntity> = shapes.into_iter().map(|shape| DxfEntity { layer: "0".into(), shape }).collect();
|
||
let dxf = write_dxf_drawing(&[], &ents);
|
||
let back = read_dxf(&dxf).unwrap();
|
||
assert_eq!(back.len(), 6, "{back:?}");
|
||
assert!(matches!(&back[0], Geom2::Line(a, b) if a.dist(Vec2::ZERO) < 1e-9 && b.dist(Vec2::new(10.0, 0.0)) < 1e-9));
|
||
assert!(matches!(&back[1], Geom2::Circle(c, r) if c.dist(Vec2::new(5.0, 5.0)) < 1e-9 && (r - 2.0).abs() < 1e-9));
|
||
assert!(
|
||
matches!(&back[2], Geom2::Arc { c, a, b } if c.dist(Vec2::ZERO) < 1e-9 && a.dist(Vec2::new(3.0, 0.0)) < 1e-9 && b.dist(Vec2::new(0.0, 3.0)) < 1e-9)
|
||
);
|
||
// The whole ellipse: centre, end of the major axis, minor radius.
|
||
assert!(
|
||
matches!(&back[3], Geom2::Ellipse { c, major, minor } if c.dist(Vec2::new(50.0, 40.0)) < 1e-9 && major.dist(Vec2::new(75.0, 40.0)) < 1e-9 && (minor - 12.0).abs() < 1e-9),
|
||
"{:?}",
|
||
back[3]
|
||
);
|
||
// The reader makes an elliptical arc a spline through points of it: from (75, 40) to (50, 52).
|
||
let Geom2::Spline { pts, control: false, .. } = &back[4] else { panic!("{:?}", back[4]) };
|
||
let on_ellipse = |p: &Vec2| (((p.x - 50.0) / 25.0).powi(2) + ((p.y - 40.0) / 12.0).powi(2) - 1.0).abs() < 1e-9;
|
||
assert!(
|
||
pts.first().is_some_and(|p| p.dist(Vec2::new(75.0, 40.0)) < 1e-9) && pts.last().is_some_and(|p| p.dist(Vec2::new(50.0, 52.0)) < 1e-9)
|
||
);
|
||
assert!(pts.iter().all(on_ellipse));
|
||
// The cubic: degree and control points.
|
||
let Geom2::Spline { pts, control: true, degree: 3 } = &back[5] else { panic!("{:?}", back[5]) };
|
||
assert!(pts.iter().zip(&cubic).all(|(a, b)| a.dist(*b) < 1e-9) && pts.len() == 4);
|
||
|
||
// The numbers in the file itself, which the reader does not keep: the ellipse...
|
||
let file = entities(&dxf);
|
||
assert_eq!(file.iter().map(|e| e.0.as_str()).collect::<Vec<_>>(), ["LINE", "CIRCLE", "ARC", "ELLIPSE", "ELLIPSE", "SPLINE"]);
|
||
assert!(near(&values(&file[3], 10), &[50.0]) && near(&values(&file[3], 20), &[40.0]) && near(&values(&file[3], 11), &[25.0]));
|
||
assert!(near(&values(&file[3], 21), &[0.0]) && near(&values(&file[3], 40), &[0.48]) && near(&values(&file[3], 41), &[0.0]));
|
||
assert!(near(&values(&file[3], 42), &[TAU]) && near(&values(&file[3], 230), &[1.0]));
|
||
// ...the elliptical arc from parameter 0 to π/2...
|
||
assert!(near(&values(&file[4], 41), &[0.0]) && near(&values(&file[4], 42), &[FRAC_PI_2]) && near(&values(&file[4], 40), &[0.48]));
|
||
// ...and the spline: planar, degree 3, eight knots, four control points.
|
||
let spline = &file[5];
|
||
assert_eq!(values(spline, 70), [8.0]);
|
||
assert_eq!((values(spline, 71), values(spline, 72), values(spline, 73), values(spline, 74)), (vec![3.0], vec![8.0], vec![4.0], vec![0.0]));
|
||
assert!(near(&values(spline, 40), &[0.0, 0.0, 0.0, 0.0, 1.0, 1.0, 1.0, 1.0]));
|
||
assert!(near(&values(spline, 10), &[0.0, 5.0, 15.0, 20.0]) && near(&values(spline, 20), &[0.0, 10.0, 10.0, 0.0]));
|
||
assert!(values(spline, 41).is_empty());
|
||
}
|
||
|
||
#[test]
|
||
fn a_rational_spline_lists_knots_then_weights_then_control_points() {
|
||
let hyperbola = seg_shape(&Seg2::Conic { a: Vec2::ZERO, apex: Vec2::new(1.0, 2.0), b: Vec2::new(3.0, 0.0), w: 2.0 });
|
||
let dxf = write_dxf_drawing(&[], &[DxfEntity { layer: "0".into(), shape: hyperbola }]);
|
||
let e = &entities(&dxf)[0];
|
||
assert_eq!(values(e, 70), [12.0]);
|
||
assert!(near(&values(e, 41), &[1.0, 2.0, 1.0]) && near(&values(e, 40), &[0.0, 0.0, 0.0, 1.0, 1.0, 1.0]));
|
||
let at = |code: i32| e.1.iter().position(|(c, _)| *c == code).unwrap();
|
||
let last = |code: i32| e.1.iter().rposition(|(c, _)| *c == code).unwrap();
|
||
assert!(last(40) < at(41) && last(41) < at(10), "{:?}", e.1);
|
||
}
|
||
}
|