diff --git a/common/main/gauges.h b/common/main/gauges.h
index f3c8d7d91..e84bb5a4b 100644
--- a/common/main/gauges.h
+++ b/common/main/gauges.h
@@ -103,7 +103,7 @@ constexpr rgb_array_wrapper player_rgb{};
 // window user is one of the WBU_ constants.  If rear_view_flag is
 // set, show a rear view.  If label is non-NULL, print the label at
 // the top of the window.
-void do_cockpit_window_view(int win, vobjptridx_t viewer, int rear_view_flag, int user, const char *label);
+void do_cockpit_window_view(int win, vobjptr_t viewer, int rear_view_flag, int user, const char *label);
 void do_cockpit_window_view(int win, int user);
 #endif
 
diff --git a/similar/main/gauges.cpp b/similar/main/gauges.cpp
index 6106686e9..cbe450ae5 100644
--- a/similar/main/gauges.cpp
+++ b/similar/main/gauges.cpp
@@ -3272,7 +3272,7 @@ void do_cockpit_window_view(int win,int user)
 	}
 }
 
-void do_cockpit_window_view(int win,const vobjptridx_t viewer,int rear_view_flag,int user,const char *label)
+void do_cockpit_window_view(int win,const vobjptr_t viewer,int rear_view_flag,int user,const char *label)
 {
 	grs_canvas window_canv;
 	static grs_canvas overlap_canv;