diff --git a/src/stores/useModelStore.ts b/src/stores/useModelStore.ts
index d0f3a36..22461e5 100644
--- a/src/stores/useModelStore.ts
+++ b/src/stores/useModelStore.ts
@@ -1,5 +1,53 @@
 import { create } from 'zustand';
 
+// ── Persistência de placement (fineTuning + escala) e flags WebXR ─────
+const PLACEMENT_KEY = 'tsxr_placements_v1';
+const XRFEAT_KEY = 'xrFeatures';
+
+export interface XRFeatureFlags {
+  handTracking: boolean;
+  planeDetection: boolean;
+  hitTest: boolean;
+  domOverlay: boolean;
+  anchors: boolean;
+  meshDetection: boolean;
+  depthSensing: boolean;
+  layers: boolean;
+  bodyTracking: boolean;
+}
+const DEFAULT_XR_FEATURES: XRFeatureFlags = {
+  handTracking: true, planeDetection: true, hitTest: true, domOverlay: true,
+  anchors: true, meshDetection: true, depthSensing: true, layers: true,
+  bodyTracking: true,
+};
+function loadXRFeatures(): XRFeatureFlags {
+  try {
+    const raw = localStorage.getItem(XRFEAT_KEY);
+    if (raw) return { ...DEFAULT_XR_FEATURES, ...JSON.parse(raw) };
+  } catch {}
+  return { ...DEFAULT_XR_FEATURES };
+}
+function saveXRFeatures(f: XRFeatureFlags) {
+  try { localStorage.setItem(XRFEAT_KEY, JSON.stringify(f)); } catch {}
+}
+
+interface StoredPlacement { fineTuning: FineTuning; }
+function loadPlacements(): Record<string, StoredPlacement> {
+  try {
+    const raw = localStorage.getItem(PLACEMENT_KEY);
+    if (raw) return JSON.parse(raw);
+  } catch {}
+  return {};
+}
+function savePlacement(fileName: string, fineTuning: FineTuning) {
+  try {
+    const all = loadPlacements();
+    all[fileName] = { fineTuning };
+    localStorage.setItem(PLACEMENT_KEY, JSON.stringify(all));
+  } catch {}
+}
+
+
 export interface ScaleRatio {
   label: string;     // e.g. "1:50", "2:1", "1:1"
   factor: number;    // render multiplier: 1:50 => 0.02, 2:1 => 2, 1:1 => 1