window: Track output scales
diff --git a/clients/window.h b/clients/window.h
index 7db9c63..c0a7cb6 100644
--- a/clients/window.h
+++ b/clients/window.h
@@ -504,6 +504,9 @@
 enum wl_output_transform
 output_get_transform(struct output *output);
 
+uint32_t
+output_get_scale(struct output *output);
+
 void
 keysym_modifiers_add(struct wl_array *modifiers_map,
 		     const char *name);