Add zDirection to options

src/ol/source/OSM.js

@@ -39,6 +39,9 @@ export const ATTRIBUTION =
  * @property {string} [url='https://{a-c}.tile.openstreetmap.org/{z}/{x}/{y}.png'] URL template.
  * Must include `{x}`, `{y}` or `{-y}`, and `{z}` placeholders.
  * @property {boolean} [wrapX=true] Whether to wrap the world horizontally.
+ * @property {number|import("../array.js").NearestDirectionFunction} [zDirection=0]
+ * Choose whether to use tiles with a higher or lower zoom level when between integer
+ * zoom levels. See {@link module:ol/tilegrid/TileGrid~TileGrid#getZForResolution}.
  */
 
 /**
@@ -81,6 +84,7 @@ class OSM extends XYZ {
       transition: options.transition,
       url: url,
       wrapX: options.wrapX,
+      zDirection: options.zDirection,
     });
   }
 }