diff --git a/web/pose_3d.js b/web/pose_3d.js
index 6bedc7e..3ad8f1c 100644
--- a/web/pose_3d.js
+++ b/web/pose_3d.js
@@ -784,6 +784,7 @@ async function pollState() {
     updateNuwaInputsFromCfg();
     updateD435InputsFromCfg();
     applyCloudParamsFromCfg(s.cloud_params);
+    applyCrossCameraFromCfg(s.cross_camera);
     applyCalibratedD435UCS();
     // Applica TUTTI i giunti reali sul modello URDF (29 motori G1)
     state.joints = s.joints || null;  // snapshot per tag locator save
@@ -1972,6 +1973,75 @@ async function pollTags() {
   }
 }
 
+// Costruisce una THREE.Matrix4 (row-major via .set) da {scale,R,t}: p' = s·R·p + t.
+function matrixFromAlign(cc) {
+  if (!cc || !Array.isArray(cc.R) || cc.R.length !== 3 || !Array.isArray(cc.t)) return null;
+  const s = Number.isFinite(cc.scale) ? cc.scale : 1;
+  const R = cc.R, t = cc.t;
+  return new THREE.Matrix4().set(
+    s*R[0][0], s*R[0][1], s*R[0][2], t[0],
+    s*R[1][0], s*R[1][1], s*R[1][2], t[1],
+    s*R[2][0], s*R[2][1], s*R[2][2], t[2],
+    0, 0, 0, 1,
+  );
+}
+
+async function doAlign() {
+  const ids = ($('p3FrontTagIds')?.value || '0-49').trim();
+  const alignId = parseInt($('p3AlignTagId')?.value, 10) || 0;
+  const status = $('p3AlignStatus');
+  if (status) { status.textContent = 'allineamento…'; status.style.color = 'var(--dim)'; }
+  try {
+    const r = await jsonFetch(
+      `/api/pose_3d/align?ids=${encodeURIComponent(ids)}&align_id=${alignId}`,
+      { method: 'POST' });
+    if (!r.found_in_both) {
+      if (status) { status.textContent = r.error || 'tag non visto da entrambe'; status.style.color = 'var(--danger)'; }
+      return;
+    }
+    state.align.matrix = matrixFromAlign(r);
+    state.align.id = r.align_id;
+    if (status) {
+      status.textContent = `scala=${r.scale.toFixed(3)} · rmse=${r.rmse_mm.toFixed(1)}mm · n=${r.n_corners}`;
+      status.style.color = 'var(--ok)';
+    }
+    applyNuwaCloudPlacement();
+  } catch (e) {
+    if (status) { status.textContent = `errore: ${e?.message || e}`; status.style.color = 'var(--danger)'; }
+  }
+}
+
+// Persistenza del solo flag + align_id (la matrice la salva il backend in /align).
+async function saveCrossCameraFlag() {
+  try {
+    await jsonFetch('/api/config', {
+      method: 'PUT',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ pose_3d: { cross_camera: {
+        enabled: $('p3AlignEnabled')?.checked === true,
+        align_id: parseInt($('p3AlignTagId')?.value, 10) || 0,
+      } } }),
+    });
+  } catch (e) { console.warn('[pose_3d] save cross_camera failed:', e?.message || e); }
+}
+
+// Ripopola UI + matrice dalla config (guardato come applyCloudParamsFromCfg).
+function applyCrossCameraFromCfg(cc) {
+  if (state.cross_camera_populated) return;
+  if (!cc || Object.keys(cc).length === 0) { state.cross_camera_populated = true; return; }
+  const en = $('p3AlignEnabled'); if (en) en.checked = cc.enabled === true;
+  const id = $('p3AlignTagId'); if (id && Number.isFinite(cc.align_id)) id.value = String(cc.align_id);
+  state.align.enabled = cc.enabled === true;
+  state.align.id = cc.align_id || 0;
+  const m = matrixFromAlign(cc);
+  if (m) state.align.matrix = m;
+  const status = $('p3AlignStatus');
+  if (status && Number.isFinite(cc.rmse_mm)) {
+    status.textContent = `caricata · scala=${(cc.scale||1).toFixed(3)} · rmse=${cc.rmse_mm.toFixed(1)}mm`;
+  }
+  state.cross_camera_populated = true;
+}
+
 function bindFrontTagFinder() {
   const cb = $('p3ShowFrontTags');
   if (!cb) return;
@@ -1990,6 +2060,13 @@ function bindFrontTagFinder() {
 
 function bindCloudControls() {
   $('p3CloudAcquireBtn')?.addEventListener('click', acquireClouds);
+  $('p3AlignBtn')?.addEventListener('click', doAlign);
+  $('p3AlignEnabled')?.addEventListener('change', () => {
+    state.align.enabled = $('p3AlignEnabled').checked === true;
+    saveCrossCameraFlag();
+    applyNuwaCloudPlacement();
+  });
+  $('p3AlignTagId')?.addEventListener('change', saveCrossCameraFlag);
   $('p3CloudClearBtn')?.addEventListener('click', clearClouds);
   $('p3ShowNuwaCloud')?.addEventListener('change', applyCloudVisibility);
   $('p3ShowD435Cloud')?.addEventListener('change', applyCloudVisibility);