diff --git a/src/tools/snapping.test.ts b/src/tools/snapping.test.ts
index e154ec8..469a0ef 100644
--- a/src/tools/snapping.test.ts
+++ b/src/tools/snapping.test.ts
@@ -12,7 +12,7 @@
 import { describe, it, expect } from "vitest";
 import { computeSnap, wallLayerBoundarySegments } from "./snapping";
 import { DEFAULT_SNAP } from "./types";
-import type { Project, Vec2, Wall } from "../model/types";
+import type { Drawing2D, Project, Vec2, Wall } from "../model/types";
 
 /** Minimalprojekt mit einer dreischichtigen Wand (0.1 / 0.15 / 0.2 m). */
 function wallProject(wall: Wall): Project {
@@ -134,3 +134,95 @@ describe("computeSnap — fängt auf Wand-Schichttrennlinien", () => {
     expect(result!.point.y).toBeCloseTo(0.025, 6);
   });
 });
+
+// ── Kreis-/Bogen-Snaps (Center/Quadrant/Bogen-Endpunkt) ──────────────────────
+
+/** Minimalprojekt mit gegebenen 2D-Geometrien auf dem Geschoss „eg". */
+function drawProject(geoms: Drawing2D["geom"][]): Project {
+  return {
+    id: "t",
+    name: "T",
+    lineStyles: [],
+    hatches: [],
+    components: [{ id: "c", name: "C", color: "#ccc", hatchId: "none", joinPriority: 10 }],
+    wallTypes: [],
+    drawingLevels: [
+      {
+        id: "eg",
+        name: "EG",
+        kind: "floor",
+        visible: true,
+        locked: false,
+        floorHeight: 2.6,
+        cutHeight: 1.0,
+        baseElevation: 0,
+      },
+    ],
+    layers: [{ code: "20", name: "Zeichnung", color: "#0a0a0a", lw: 0.5, visible: true, locked: false }],
+    walls: [],
+    doors: [],
+    openings: [],
+    ceilings: [],
+    stairs: [],
+    rooms: [],
+    drawings2d: geoms.map((geom, i) => ({
+      id: `d${i}`,
+      type: "drawing2d" as const,
+      levelId: "eg",
+      categoryCode: "20",
+      geom,
+    })),
+    context: [],
+  };
+}
+
+function snapAt(project: Project, raw: Vec2, settings = DEFAULT_SNAP) {
+  return computeSnap({
+    raw,
+    project,
+    levelId: "eg",
+    visibleCodes: new Set(["20"]),
+    settings,
+    draftPoints: [],
+    lastPoint: null,
+    pxPerMeter: 100,
+    shift: false,
+    ctrl: false,
+  });
+}
+
+describe("computeSnap — Kreis/Bogen", () => {
+  const withCenter = { ...DEFAULT_SNAP, center: true };
+
+  it("fängt Mittelpunkt + Quadranten eines Kreises (center aktiv)", () => {
+    const p = drawProject([{ shape: "circle", center: { x: 0, y: 0 }, r: 1 }]);
+    const c = snapAt(p, { x: 0, y: 0 }, withCenter);
+    expect(c?.kind).toBe("center");
+    expect(c!.point.x).toBeCloseTo(0, 6);
+    expect(c!.point.y).toBeCloseTo(0, 6);
+    const q = snapAt(p, { x: 1, y: 0 }, withCenter);
+    expect(q?.kind).toBe("quadrant");
+    expect(q!.point.x).toBeCloseTo(1, 6);
+    expect(q!.point.y).toBeCloseTo(0, 6);
+  });
+
+  it("fängt Bogen-Endpunkte (endpoint per Default aktiv)", () => {
+    // Viertelbogen um (5,0), r=1, 0…90° → Endpunkte (6,0) und (5,1).
+    const p = drawProject([
+      { shape: "arc", center: { x: 5, y: 0 }, r: 1, a0: 0, a1: Math.PI / 2 },
+    ]);
+    const e = snapAt(p, { x: 6, y: 0 });
+    expect(e?.kind).toBe("endpoint");
+    expect(e!.point.x).toBeCloseTo(6, 6);
+    expect(e!.point.y).toBeCloseTo(0, 6);
+  });
+
+  it("bietet Quadranten AUSSERHALB der Bogen-Spanne NICHT an", () => {
+    // Viertelbogen 0…90°: der West-Quadrant (4,0) liegt NICHT im Bogen.
+    const p = drawProject([
+      { shape: "arc", center: { x: 5, y: 0 }, r: 1, a0: 0, a1: Math.PI / 2 },
+    ]);
+    const r = snapAt(p, { x: 4, y: 0 }, withCenter);
+    expect(r?.kind).not.toBe("quadrant");
+  });
+});
diff --git a/src/tools/snapping.ts b/src/tools/snapping.ts
index 3321b29..4bbbe9a 100644
--- a/src/tools/snapping.ts
+++ b/src/tools/snapping.ts
@@ -108,6 +108,28 @@ function collectSegments(input: SnapInput): Seg[] {
   return segs;
 }
 
+/** Kreis-/Bogen-Geometrie für Center-/Quadrant-/Endpunkt-Snaps. `arc=null` =
+ *  Vollkreis (keine Endpunkte, alle vier Quadranten). */
+interface CircleGeom {
+  center: Vec2;
+  r: number;
+  arc: { a0: number; a1: number } | null;
+}
+
+/** Sammelt sichtbare Kreise/Bögen des aktiven Geschosses (aus `drawings2d`). */
+function collectCircles(input: SnapInput): CircleGeom[] {
+  const out: CircleGeom[] = [];
+  for (const d of input.project.drawings2d) {
+    if (d.levelId !== input.levelId) continue;
+    if (!input.visibleCodes.has(d.categoryCode)) continue;
+    const g = d.geom;
+    if (g.shape === "circle") out.push({ center: g.center, r: g.r, arc: null });
+    else if (g.shape === "arc")
+      out.push({ center: g.center, r: g.r, arc: { a0: g.a0, a1: g.a1 } });
+  }
+  return out;
+}
+
 /** Lotfußpunkt von p auf die Strecke a-b, auf das Segment geklemmt. */
 function perpFoot(p: Vec2, a: Vec2, b: Vec2): Vec2 {
   const dx = b.x - a.x, dy = b.y - a.y;
@@ -184,6 +206,34 @@ export function computeSnap(input: SnapInput): SnapResult | null {
     for (const [a, b] of segs) consider(perpFoot(raw, a, b), "onEdge");
   }
 
+  // Kreis-/Bogen-Snaps: Mittelpunkt + Quadranten (Ost/Nord/West/Süd); bei Bögen
+  // nur die Quadranten IM Bogen-Bereich, plus die beiden Bogen-Endpunkte. Center/
+  // Quadrant hängen an der `center`-Einstellung, die Endpunkte an `endpoint`.
+  if (settings.center || settings.endpoint) {
+    const TAU = Math.PI * 2;
+    const norm = (x: number) => ((x % TAU) + TAU) % TAU;
+    const onCircle = (c: CircleGeom, ang: number): Vec2 => ({
+      x: c.center.x + c.r * Math.cos(ang),
+      y: c.center.y + c.r * Math.sin(ang),
+    });
+    for (const c of collectCircles(input)) {
+      if (settings.center) {
+        consider(c.center, "center");
+        // Volle CCW-Spanne (0 ⇒ Vollkreis); Quadrant nur, wenn im Bogen liegt.
+        const sweep = c.arc ? norm(c.arc.a1 - c.arc.a0) || TAU : TAU;
+        for (let q = 0; q < 4; q++) {
+          const ang = q * (Math.PI / 2);
+          if (c.arc && norm(ang - c.arc.a0) > sweep + 1e-9) continue;
+          consider(onCircle(c, ang), "quadrant");
+        }
+      }
+      if (settings.endpoint && c.arc) {
+        consider(onCircle(c, c.arc.a0), "endpoint");
+        consider(onCircle(c, c.arc.a1), "endpoint");
+      }
+    }
+  }
+
   if (best) return best;
 
   // Ortho / Winkelraster (Projektion relativ zum letzten Punkt).