DXF-Import: CIRCLE/ARC als echte glatte Kreis-/Bogen-Formen (statt tesselliertem Vieleck)

src/io/dxfParser.test.ts

@@ -471,6 +471,52 @@ describe("textsToDrawings", () => {
   });
 });
 
+describe("parseDxf — Kurven behalten echte Geometrie (curve)", () => {
+  it("CIRCLE trägt curve {kind:circle}", () => {
+    const c = onlyContour(dxf(circle(10, 20, 5, 4)));
+    expect(c.curve?.kind).toBe("circle");
+    expect(c.curve?.cx).toBeCloseTo(10, 9);
+    expect(c.curve?.cy).toBeCloseTo(20, 9);
+    expect(c.curve?.r).toBeCloseTo(4, 9);
+  });
+
+  it("ARC trägt curve {kind:arc} mit Winkeln (Radiant)", () => {
+    const c = onlyContour(dxf(arc(0, 0, 10, 0, 90)));
+    expect(c.curve?.kind).toBe("arc");
+    expect(c.curve?.r).toBeCloseTo(10, 9);
+    expect(c.curve?.a0).toBeCloseTo(0, 9);
+    expect(c.curve?.a1).toBeCloseTo(Math.PI / 2, 9);
+  });
+});
+
+describe("contoursToDrawings — Kurven → glatte Formen", () => {
+  it("curve circle → {shape:\"circle\"}", () => {
+    const set: ContourSet = {
+      id: "s", type: "contourSet", name: "c",
+      contours: [{ z: 0, closed: true, pts: [{ x: 0, y: 0 }], curve: { kind: "circle", cx: 1, cy: 2, r: 3, a0: 0, a1: Math.PI * 2 } }],
+    };
+    const [d] = contoursToDrawings([set], "lvl", "active", "C", (s) => s);
+    expect(d.geom.shape).toBe("circle");
+    if (d.geom.shape === "circle") {
+      expect(d.geom.r).toBeCloseTo(3, 9);
+      expect(d.geom.center.x).toBeCloseTo(1, 9);
+    }
+  });
+
+  it("curve arc → {shape:\"arc\"}", () => {
+    const set: ContourSet = {
+      id: "s", type: "contourSet", name: "c",
+      contours: [{ z: 0, closed: false, pts: [{ x: 0, y: 0 }], curve: { kind: "arc", cx: 0, cy: 0, r: 5, a0: 0, a1: 1 } }],
+    };
+    const [d] = contoursToDrawings([set], "lvl", "active", "C", (s) => s);
+    expect(d.geom.shape).toBe("arc");
+    if (d.geom.shape === "arc") {
+      expect(d.geom.r).toBeCloseTo(5, 9);
+      expect(d.geom.a1).toBeCloseTo(1, 9);
+    }
+  });
+});
+
 describe("contoursToDrawings — HATCH-Füllung", () => {
   it("gefüllte Kontur → Drawing2D mit fillColor und polyline-Form", () => {
     const set: ContourSet = {

src/io/dxfParser.ts

@@ -444,7 +444,13 @@ function arcContour(e: DxfEntity): Contour | null {
     const t = start + (sweep * i) / segs;
     pts.push({ x: cx + r * Math.cos(t), y: cy + r * Math.sin(t) });
   }
-  return { z, pts, closed: false, layer: e.layer };
+  return {
+    z,
+    pts,
+    closed: false,
+    layer: e.layer,
+    curve: { kind: "arc", cx, cy, r, a0: start, a1: start + sweep },
+  };
 }
 
 /** CIRCLE → geschlossener Kreis-Linienzug (voller Umlauf, letzter Punkt weggelassen). */
@@ -471,7 +477,13 @@ function circleContour(e: DxfEntity): Contour | null {
     const t = (Math.PI * 2 * i) / segs;
     pts.push({ x: cx + r * Math.cos(t), y: cy + r * Math.sin(t) });
   }
-  return { z, pts, closed: true, layer: e.layer };
+  return {
+    z,
+    pts,
+    closed: true,
+    layer: e.layer,
+    curve: { kind: "circle", cx, cy, r, a0: 0, a1: Math.PI * 2 },
+  };
 }
 
 /**

src/io/dxfToDrawings.ts

@@ -102,6 +102,14 @@ export function textsToDrawings(
 
 /** Eine Kontur → 2D-Geometrie (line bei 2 offenen Punkten, sonst polyline). */
 function contourGeom(contour: Contour): Drawing2DGeom | null {
+  // Echte Kurve (CIRCLE/ARC) → GLATTE Kreis-/Bogen-Form statt tesselliertem Vieleck.
+  const c = contour.curve;
+  if (c) {
+    if (c.kind === "circle") {
+      return { shape: "circle", center: { x: c.cx, y: c.cy }, r: c.r };
+    }
+    return { shape: "arc", center: { x: c.cx, y: c.cy }, r: c.r, a0: c.a0, a1: c.a1 };
+  }
   const pts = contour.pts;
   if (pts.length < 2) return null;
   if (pts.length === 2 && !contour.closed) {