BatchedMesh: addUpdateRanges (#27981)

src/objects/BatchedMesh.js

@@ -514,6 +514,7 @@ class BatchedMesh extends Mesh {
 			}
 
 			dstAttribute.needsUpdate = true;
+			dstAttribute.addUpdateRange( vertexStart * itemSize, vertexCount * itemSize );
 
 		}
 
@@ -537,6 +538,7 @@ class BatchedMesh extends Mesh {
 			}
 
 			dstIndex.needsUpdate = true;
+			dstIndex.addUpdateRange( indexStart, reservedRange.indexCount );
 
 		}