diff --git a/src/lib/modelTransforms.ts b/src/lib/modelTransforms.ts
index 58d8807..c3ef211 100644
--- a/src/lib/modelTransforms.ts
+++ b/src/lib/modelTransforms.ts
@@ -33,3 +33,25 @@ export function worldToModelLocal(
   g.worldToLocal(v);
   return { x: v.x, y: v.y, z: v.z };
 }
+
+export function modelLocalToWorld(
+  modelId: string | null | undefined,
+  p: { x: number; y: number; z: number },
+): { x: number; y: number; z: number } | null {
+  const g = getModelLocalGroup(modelId);
+  if (!g) return null;
+  g.updateWorldMatrix(true, false);
+  const v = new THREE.Vector3(p.x, p.y, p.z);
+  g.localToWorld(v);
+  return { x: v.x, y: v.y, z: v.z };
+}
+
+export function getModelWorldScaleFactor(modelId: string | null | undefined): number {
+  const g = getModelLocalGroup(modelId);
+  if (!g) return 1;
+  g.updateWorldMatrix(true, false);
+  const s = new THREE.Vector3();
+  g.getWorldScale(s);
+  const factor = (Math.abs(s.x) + Math.abs(s.y) + Math.abs(s.z)) / 3;
+  return Number.isFinite(factor) && factor > 1e-6 ? factor : 1;
+}