scale spawned object to match given bounding sphere diameter

Assets/_PROJECT/Scripts/ModeGeneration/ModelGenerationUtils.cs

@@ -76,7 +76,7 @@ public class ModelGenerationUtils : MonoBehaviour
                     }
                 }
 
-                throw new System.Exception("Failed to generate 3D model!");
+                throw new Exception("Failed to generate 3D model!");
             }
         });
     }
@@ -96,22 +96,22 @@ public class ModelGenerationUtils : MonoBehaviour
             return await SpawnModel(gltf, objectName);
         }
 
-        throw new System.Exception("Failed to load GameObject from model" + modelPath);
+        throw new Exception("Failed to load GameObject from model" + modelPath);
     }
 
-    public async Task<GameObject> SpawnModel(byte[] modelBinary)
+    public async Task<GameObject> SpawnModel(byte[] modelBinary, float boundingSphereDiameter = 0)
     {
         var gltf = new GltfImport();
         bool loadSuccess = await gltf.Load(modelBinary);
         if (loadSuccess)
         {
-            return await SpawnModel(gltf, "GeneratedModel");
+            return await SpawnModel(gltf, "GeneratedModel", boundingSphereDiameter);
         }
 
-        throw new System.Exception("Failed to load GameObject from binary!");
+        throw new Exception("Failed to load GameObject from binary!");
     }
 
-    public async Task<GameObject> SpawnModel(GltfImport gltfImport, string objectName)
+    public async Task<GameObject> SpawnModel(GltfImport gltfImport, string objectName, float boundingSphereDiameter = 0)
     {
         GameObject spawningParent = new GameObject("Parent-" + objectName);
 
@@ -125,11 +125,54 @@ public class ModelGenerationUtils : MonoBehaviour
             MeshRenderer renderer = spawnedObjectBody.GetComponent<MeshRenderer>();
             renderer.material.SetFloat("metallicFactor", 0);
 
+            AdjustScale(spawnedObjectBody, collider, boundingSphereDiameter);
+
             spawnedObjectBody.name = objectName;
             return spawnedObjectBody;
         }
 
-        throw new System.Exception("Failed to spawn GameObject " + objectName);
+        throw new Exception("Failed to spawn GameObject " + objectName);
+    }
+
+    private async void AdjustScale(GameObject obj, MeshCollider collider, float boundingSphereDiameter)
+    {
+
+        // Wait one frame to ensure collider cooking & bounds are valid
+        await Task.Yield();
+
+        // --- Compute current bounding sphere diameter (from world AABB) ---
+        Bounds b = collider.bounds; // world-space AABB
+        float currentDiameter = 2f * b.extents.magnitude;
+
+        if (boundingSphereDiameter <= 0f)
+        {
+            UnityEngine.Debug.Log("Not adjusting scale");
+            return;
+        }
+
+        if (currentDiameter <= Mathf.Epsilon)
+            throw new Exception("Spawned mesh has zero-sized bounds; cannot scale to target diameter.");
+
+        // --- Compute and apply uniform scale ---
+        float scaleFactor = boundingSphereDiameter / currentDiameter;
+        obj.transform.localScale *= scaleFactor;
+
+        // Give Unity a moment to recompute bounds after scaling, then do a corrective pass
+        await Task.Yield();
+
+        // Corrective pass (optional): re-measure and nudge scale to reduce residual error
+        Bounds b2 = collider.bounds;
+        float newDiameter = 2f * b2.extents.magnitude;
+
+        // Only correct if off by more than a tiny epsilon (1%)
+        const float tolerance = 0.01f; // 1%
+        float err = Mathf.Abs(newDiameter - boundingSphereDiameter) / boundingSphereDiameter;
+        if (err > tolerance && newDiameter > Mathf.Epsilon)
+        {
+            float correction = boundingSphereDiameter / newDiameter;
+            obj.transform.localScale *= correction;
+            // No need to wait again unless you need to read back the final diameter immediately
+        }
     }
 
 

Assets/_PROJECT/Scripts/ModeGeneration/NPCs/CafeWaiterNPC.cs

@@ -13,6 +13,7 @@ public class CafeWaiterNPC : NPCController
     public Transform backRoom;
     public Transform plate;
     public float backRoomMovingTime = 5f;
+    public float spawnedFoodDiameter = 0.5f;
 
     public int ignorePlayerCollisionLayer = 2;
 
@@ -135,7 +136,7 @@ public class CafeWaiterNPC : NPCController
         Sprite sprite = ModelGenerationUtils.CreateSprite(GeneratedTexture);
         string encodedTexture = Convert.ToBase64String(GeneratedTexture.EncodeToJPG());
         byte[] encodedModel = await TrellisClient.Instance.GenerateModel(encodedTexture);
-        GameObject spawnedObject = await ModelGenerationUtils.Instance.SpawnModel(encodedModel);
+        GameObject spawnedObject = await ModelGenerationUtils.Instance.SpawnModel(encodedModel, spawnedFoodDiameter);
 
         // Come back
         transform.DOMove(startingPosition, backRoomMovingTime).OnComplete(() =>
@@ -160,6 +161,7 @@ public class CafeWaiterNPC : NPCController
         spawnedObjectCollider.convex = true;
         spawnedObject.layer = ignorePlayerCollisionLayer;
 
-        spawnedObject.AddComponent<XRGrabInteractable>();
+        XRGrabInteractable grabComponent = spawnedObject.AddComponent<XRGrabInteractable>();
+        grabComponent.useDynamicAttach = true;
     }
 }