diff --git a/public/admin/plan.html b/public/admin/plan.html
new file mode 100644
index 0000000..dfa258a
--- /dev/null
+++ b/public/admin/plan.html
@@ -0,0 +1,237 @@
+<!doctype html>
+<html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1">
+<title>Placement Plan — Newbury Exhibit</title>
+<style>
+  body { font-family: system-ui, sans-serif; margin: 0; background: #666; }
+  #controls { padding: 10px 16px; display: flex; gap: 14px; flex-wrap: wrap; align-items: center; background: #0d1226; color: #e8ecff; }
+  .page { background: #fff; color: #000; margin: 10px auto; box-shadow: 0 2px 10px rgba(0,0,0,.5); position: relative; overflow: hidden; }
+  .page svg { display: block; }
+  .pgHead { position: absolute; top: 2mm; left: 5mm; right: 5mm; font-size: 8pt; display: flex; justify-content: space-between; }
+  @media print {
+    body { background: #fff; }
+    #hdr, #controls { display: none !important; }
+    .page { margin: 0; box-shadow: none; page-break-after: always; }
+  }
+</style></head>
+<body>
+<div id="hdr"></div>
+<div id="controls"></div>
+<div id="pages"></div>
+
+<script src="/vendor/cv.js"></script>
+<script src="/vendor/svd.js"></script>
+<script src="/vendor/posit1.js"></script>
+<script src="/vendor/aruco.js"></script>
+<script src="/vendor/dictionaries/aruco_4x4_1000.js"></script>
+<script type="module">
+import { requireAuth, styles, nav } from './admin.js';
+document.getElementById('hdr').innerHTML = nav('plan');
+document.head.insertAdjacentHTML('beforeend', `<style>@media screen {${styles}}</style>`);
+await requireAuth();
+
+const scene = await (await fetch('/api/scene')).json();
+const dic = new AR.Dictionary('ARUCO_4X4_1000');
+
+const PAPER = { A4: [210, 297], A3: [297, 420] };
+const MARGIN = 10;   // mm printable margin
+const OVERLAP = 10;  // mm tile overlap for joining
+
+const opts = { scale: '1', paper: 'A4', anchors: true, buildings: true, spawns: true, paths: true };
+
+document.getElementById('controls').innerHTML = `
+  <label>Scale <select id="scale">
+    <option value="1">1:1 (true size — tape it down)</option>
+    <option value="2">1:2</option>
+    <option value="5">1:5</option>
+    <option value="fit">Fit one page</option>
+  </select></label>
+  <label>Paper <select id="paper"><option>A4</option><option>A3</option></select></label>
+  ${['anchors','buildings','spawns','paths'].map(k =>
+    `<label><input type="checkbox" id="ly-${k}" checked> ${k}</label>`).join('')}
+  <span style="flex:1"></span>
+  <button class="primary" onclick="print()">Print…</button>
+  <span id="pgCount" style="opacity:.7;font-size:.85rem"></span>`;
+['scale','paper'].forEach(id => document.getElementById(id).onchange = e => { opts[id] = e.target.value; build(); });
+['anchors','buildings','spawns','paths'].forEach(k =>
+  document.getElementById('ly-' + k).onchange = e => { opts[k] = e.target.checked; build(); });
+
+// ---------- geometry ----------
+function extent() {
+  let minX = 0, minZ = 0, maxX = 100, maxZ = 100;
+  const eat = (x, z, pad = 10) => {
+    minX = Math.min(minX, x - pad); maxX = Math.max(maxX, x + pad);
+    minZ = Math.min(minZ, z - pad); maxZ = Math.max(maxZ, z + pad);
+  };
+  for (const a of scene.anchors || []) eat(a.position[0], a.position[2]);
+  for (const b of scene.buildings || []) eat(b.position[0], b.position[2], Math.max(b.size[0], b.size[2]) / 2 + 5);
+  for (const s of scene.spawns || []) eat(s.position[0], s.position[2]);
+  for (const p of scene.paths || []) for (const q of p.points || []) eat(q[0], q[2]);
+  return { minX, minZ, maxX, maxZ, w: maxX - minX, h: maxZ - minZ };
+}
+
+const brgOf = a => a.mount === 'wall'
+  ? ((a.yawDeg % 360) + 360) % 360
+  : (((180 + (a.yawDeg || 0)) % 360) + 360) % 360;
+
+/* Build the plan as SVG inner markup in mm units at scale k (world cm * 10 / k).
+ * Page mapping: +X east = right, N (+Z) = UP the page. */
+function planSVG(ex, k) {
+  const S = 10 / k;                       // mm per world-cm
+  const X = x => (x - ex.minX) * S;
+  const Y = z => (ex.maxZ - z) * S;       // N up
+  const px = v => +v.toFixed(2);
+  let g = '';
+
+  // grid: 10 cm light, 50 cm dark, labels every 50 cm
+  for (let x = Math.ceil(ex.minX / 10) * 10; x <= ex.maxX; x += 10) {
+    const major = x % 50 === 0;
+    g += `<line x1="${px(X(x))}" y1="0" x2="${px(X(x))}" y2="${px(Y(ex.minZ))}" stroke="${major ? '#999' : '#ddd'}" stroke-width="${major ? 0.3 : 0.15}"/>`;
+    if (major) g += `<text x="${px(X(x))}" y="${px(Y(ex.minZ)) - 1}" font-size="3" text-anchor="middle" fill="#666">${x}</text>`;
+  }
+  for (let z = Math.ceil(ex.minZ / 10) * 10; z <= ex.maxZ; z += 10) {
+    const major = z % 50 === 0;
+    g += `<line x1="0" y1="${px(Y(z))}" x2="${px(X(ex.maxX))}" y2="${px(Y(z))}" stroke="${major ? '#999' : '#ddd'}" stroke-width="${major ? 0.3 : 0.15}"/>`;
+    if (major) g += `<text x="1" y="${px(Y(z)) - 0.8}" font-size="3" fill="#666">${z}</text>`;
+  }
+
+  // compass rose (top-left)
+  g += `<g transform="translate(12,14)">
+    <circle r="8" fill="none" stroke="#000" stroke-width="0.4"/>
+    <path d="M0,2 L0,-6 M-1.6,-3.6 L0,-6 L1.6,-3.6" stroke="#000" stroke-width="0.7" fill="none"/>
+    <text y="-9.5" font-size="4" text-anchor="middle" font-weight="bold">N (+Z, back)</text>
+    <text y="13" font-size="3" text-anchor="middle" fill="#444">grid 10 cm</text></g>`;
+
+  if (opts.paths) for (const p of scene.paths || []) {
+    const pts = (p.points || []);
+    if (pts.length < 2) continue;
+    const lp = p.mode === 'loop' ? [...pts, pts[0]] : pts;
+    g += `<polyline points="${lp.map(q => `${px(X(q[0]))},${px(Y(q[2]))}`).join(' ')}" fill="none" stroke="#8a2be2" stroke-width="0.5" stroke-dasharray="2 1.2"/>`;
+    for (let i = 0; i < lp.length - 1; i++) {  // direction arrow per segment midpoint
+      const mx = (X(lp[i][0]) + X(lp[i + 1][0])) / 2, my = (Y(lp[i][2]) + Y(lp[i + 1][2])) / 2;
+      const ang = Math.atan2(Y(lp[i + 1][2]) - Y(lp[i][2]), X(lp[i + 1][0]) - X(lp[i][0])) * 180 / Math.PI;
+      g += `<path d="M-1.8,-1.2 L1.8,0 L-1.8,1.2 Z" transform="translate(${px(mx)},${px(my)}) rotate(${px(ang)})" fill="#8a2be2"/>`;
+    }
+    pts.forEach((q, i) => {
+      g += `<circle cx="${px(X(q[0]))}" cy="${px(Y(q[2]))}" r="1.4" fill="#fff" stroke="#8a2be2" stroke-width="0.5"/>
+        <text x="${px(X(q[0]) + 2)}" y="${px(Y(q[2]) - 1.5)}" font-size="2.6" fill="#8a2be2">${p.id}·${i + 1} (y=${q[1]})</text>`;
+    });
+  }
+
+  if (opts.buildings) for (const b of scene.buildings || []) {
+    const w = b.size[0] * S, d = b.size[2] * S;
+    g += `<g transform="translate(${px(X(b.position[0]))},${px(Y(b.position[2]))}) rotate(${px(-(b.yawDeg || 0))})">
+      <rect x="${px(-w / 2)}" y="${px(-d / 2)}" width="${px(w)}" height="${px(d)}" fill="#dbe8ff" fill-opacity="0.6" stroke="#4a7fd0" stroke-width="0.4"/>
+      <text font-size="3.2" text-anchor="middle" fill="#2a4f90">${b.name || 'building'}</text>
+      <text y="4" font-size="2.6" text-anchor="middle" fill="#2a4f90">h=${b.size[1]} cm</text></g>`;
+  }
+
+  if (opts.spawns) for (const s of scene.spawns || []) {
+    g += `<circle cx="${px(X(s.position[0]))}" cy="${px(Y(s.position[2]))}" r="2.2" fill="#ffd166" fill-opacity="0.7" stroke="#b57f0b" stroke-width="0.4"/>
+      <text x="${px(X(s.position[0]) + 3)}" y="${px(Y(s.position[2]) + 1)}" font-size="2.8" fill="#7a5500">${s.id} (y=${s.position[1]})</text>`;
+  }
+
+  if (opts.anchors) for (const a of scene.anchors || []) {
+    const cx = X(a.position[0]), cy = Y(a.position[2]);
+    const brg = brgOf(a);
+    if (a.mount === 'wall') {
+      // vertical marker: footprint line perpendicular to facing, arrow shows facing
+      const half = (a.sizeMM / 10) * S / 2;
+      g += `<g transform="translate(${px(cx)},${px(cy)}) rotate(${px(brg)})">
+        <line x1="${px(-half)}" y1="0" x2="${px(half)}" y2="0" stroke="#c0392b" stroke-width="1"/>
+        <path d="M0,0 L0,${px(-half)} M-1.5,${px(-half + 2)} L0,${px(-half)} L1.5,${px(-half + 2)}" stroke="#c0392b" stroke-width="0.5" fill="none"/></g>
+        <text x="${px(cx + half + 1)}" y="${px(cy)}" font-size="3" fill="#c0392b">#${a.markerId} WALL faces ${brg}° · y=${a.position[1]}</text>`;
+      continue;
+    }
+    // flat marker: true-size crest pattern rotated so its top edge faces brg (clockwise from N=up)
+    const sz = (a.sizeMM / 10) * S;       // mm on page
+    const cell = sz / 6;
+    const code = dic.codeList[a.markerId] || '';
+    let cells = `<rect x="${px(-sz / 2)}" y="${px(-sz / 2)}" width="${px(sz)}" height="${px(sz)}" fill="#000"/>`;
+    for (let yy = 0; yy < 4; yy++) for (let xx = 0; xx < 4; xx++)
+      if (code[yy * 4 + xx] === '1')
+        cells += `<rect x="${px(-sz / 2 + (xx + 1) * cell)}" y="${px(-sz / 2 + (yy + 1) * cell)}" width="${px(cell)}" height="${px(cell)}" fill="#fff"/>`;
+    g += `<g transform="translate(${px(cx)},${px(cy)}) rotate(${px(brg)})">${cells}
+      <path d="M0,${px(-sz / 2 - 1)} L0,${px(-sz / 2 - 5)} M-1.5,${px(-sz / 2 - 3.2)} L0,${px(-sz / 2 - 5)} L1.5,${px(-sz / 2 - 3.2)}" stroke="#0a8f6b" stroke-width="0.6" fill="none"/></g>
+      <text x="${px(cx + sz / 2 + 1.5)}" y="${px(cy + 1)}" font-size="3" fill="#0a8f6b" font-weight="bold">#${a.markerId}</text>
+      <text x="${px(cx + sz / 2 + 1.5)}" y="${px(cy + 4.5)}" font-size="2.4" fill="#0a8f6b">top→${brg}°</text>`;
+  }
+  return g;
+}
+
+// ---------- pages ----------
+function build() {
+  const ex = extent();
+  const [pw, ph] = PAPER[opts.paper];
+  const availW = pw - 2 * MARGIN, availH = ph - 2 * MARGIN;
+
+  let k;
+  if (opts.scale === 'fit') k = Math.max((ex.w * 10) / availW, (ex.h * 10) / availH, 1);
+  else k = parseFloat(opts.scale);
+
+  const S = 10 / k;
+  const totW = ex.w * S, totH = ex.h * S;   // mm
+  const inner = planSVG(ex, k);
+
+  const stepW = availW - OVERLAP, stepH = availH - OVERLAP;
+  const cols = Math.max(1, Math.ceil((totW - OVERLAP) / stepW));
+  const rows = Math.max(1, Math.ceil((totH - OVERLAP) / stepH));
+
+  const pages = document.getElementById('pages');
+  pages.innerHTML = '';
+  const scaleLabel = opts.scale === 'fit' ? `1:${k.toFixed(1)}` : `1:${k}` + (k === 1 ? ' — TRUE SIZE: crest patterns are usable, tape sheet down' : '');
+
+  // overview page (always first): whole plan fit on one page with tile grid
+  const fitK = Math.max((ex.w * 10) / availW, (ex.h * 10) / availH, 1);
+  const ovW = ex.w * 10 / fitK, ovH = ex.h * 10 / fitK;
+  let tileGrid = '';
+  if (cols * rows > 1) {
+    const rr = (10 / fitK) / S; // convert tile mm to overview mm
+    for (let r = 0; r < rows; r++) for (let c = 0; c < cols; c++) {
+      const tx = c * stepW * rr, ty = r * stepH * rr;
+      tileGrid += `<rect x="${tx.toFixed(1)}" y="${ty.toFixed(1)}" width="${(availW * rr).toFixed(1)}" height="${(availH * rr).toFixed(1)}"
+        fill="none" stroke="#e74c3c" stroke-width="0.4" stroke-dasharray="2 1"/>
+        <text x="${(tx + 2).toFixed(1)}" y="${(ty + 5).toFixed(1)}" font-size="5" fill="#e74c3c" font-weight="bold">${String.fromCharCode(65 + r)}${c + 1}</text>`;
+    }
+  }
+  pages.insertAdjacentHTML('beforeend', `
+    <div class="page" style="width:${pw}mm;height:${ph}mm">
+      <div class="pgHead"><b>Newbury Exhibit — placement plan (overview, 1:${fitK.toFixed(1)})</b>
+      <span>${cols * rows > 1 ? `${cols * rows} tile pages follow at ${scaleLabel} — red boxes show tiles` : `scale ${scaleLabel}`}</span></div>
+      <svg width="${ovW}mm" height="${ovH}mm" viewBox="0 0 ${ex.w * 10 / fitK} ${ex.h * 10 / fitK}"
+        style="margin:${MARGIN + 4}mm ${MARGIN}mm">
+        <g transform="scale(${(10 / fitK) / S})">${inner}</g>${tileGrid}
+      </svg>
+    </div>`);
+
+  // tile pages
+  if (!(opts.scale === 'fit')) {
+    for (let r = 0; r < rows; r++) for (let c = 0; c < cols; c++) {
+      const vx = c * stepW, vy = r * stepH;
+      const label = `${String.fromCharCode(65 + r)}${c + 1}`;
+      const joins = [
+        c + 1 < cols ? `right joins ${String.fromCharCode(65 + r)}${c + 2}` : '',
+        r + 1 < rows ? `bottom joins ${String.fromCharCode(66 + r)}${c + 1}` : '',
+      ].filter(Boolean).join(' · ');
+      // crop marks at the overlap boundary
+      const cm = `<g stroke="#e74c3c" stroke-width="0.3">
+        ${[[OVERLAP / 2, 0], [availW - OVERLAP / 2, 0]].map(([x]) =>
+          `<line x1="${vx + x}" y1="${vy}" x2="${vx + x}" y2="${vy + 4}"/><line x1="${vx + x}" y1="${vy + availH - 4}" x2="${vx + x}" y2="${vy + availH}"/>`).join('')}
+        ${[[0, OVERLAP / 2], [0, availH - OVERLAP / 2]].map(([, y]) =>
+          `<line x1="${vx}" y1="${vy + y}" x2="${vx + 4}" y2="${vy + y}"/><line x1="${vx + availW - 4}" y1="${vy + y}" x2="${vx + availW}" y2="${vy + y}"/>`).join('')}
+      </g>`;
+      pages.insertAdjacentHTML('beforeend', `
+        <div class="page" style="width:${pw}mm;height:${ph}mm">
+          <div class="pgHead"><b>Tile ${label}</b><span>${scaleLabel}${joins ? ' · ' + joins : ''} · overlap ${OVERLAP} mm</span></div>
+          <svg width="${availW}mm" height="${availH}mm" viewBox="${vx} ${vy} ${availW} ${availH}"
+            style="margin:${MARGIN + 4}mm ${MARGIN}mm ${MARGIN - 4}mm">
+            ${inner}${cm}
+          </svg>
+        </div>`);
+    }
+  }
+  document.getElementById('pgCount').textContent =
+    `${pages.children.length} page${pages.children.length === 1 ? '' : 's'} · plan ${ex.w}×${ex.h} cm`;
+}
+build();
+</script>
+</body></html>
