diff --git a/common/main/object.h b/common/main/object.h
index 445c29a53..df30213bd 100644
--- a/common/main/object.h
+++ b/common/main/object.h
@@ -780,7 +780,7 @@ void dead_player_frame(void);
 
 #if defined(DXX_BUILD_DESCENT_II)
 // returns object number
-objnum_t drop_marker_object(vms_vector *pos, segnum_t segnum, vms_matrix *orient, int marker_num);
+objnum_t drop_marker_object(const vms_vector &pos, segnum_t segnum, const vms_matrix &orient, int marker_num);
 
 extern void wake_up_rendered_objects(vobjptridx_t gmissp, int window_num);
 
diff --git a/similar/main/automap.cpp b/similar/main/automap.cpp
index 825f52c52..87c43ad47 100644
--- a/similar/main/automap.cpp
+++ b/similar/main/automap.cpp
@@ -309,7 +309,7 @@ static void DropMarker (int player_marker_num)
 	if (MarkerObject[marker_num] != object_none)
 		obj_delete(MarkerObject[marker_num]);
 
-	MarkerObject[marker_num] = drop_marker_object(&playerp->pos,playerp->segnum,&playerp->orient,marker_num);
+	MarkerObject[marker_num] = drop_marker_object(playerp->pos,playerp->segnum,playerp->orient,marker_num);
 
 	if (Game_mode & GM_MULTI)
 		multi_send_drop_marker (Player_num,playerp->pos,player_marker_num,MarkerMessage[marker_num]);
@@ -330,7 +330,7 @@ void DropBuddyMarker(const vobjptr_t objp)
 	if (MarkerObject[marker_num] != object_none)
 		obj_delete(MarkerObject[marker_num]);
 
-	MarkerObject[marker_num] = drop_marker_object(&objp->pos, objp->segnum, &objp->orient, marker_num);
+	MarkerObject[marker_num] = drop_marker_object(objp->pos, objp->segnum, objp->orient, marker_num);
 
 }
 
diff --git a/similar/main/multi.cpp b/similar/main/multi.cpp
index 6c1cf2e09..5e70cde0d 100644
--- a/similar/main/multi.cpp
+++ b/similar/main/multi.cpp
@@ -2225,7 +2225,7 @@ static void multi_do_drop_marker (const playernum_t pnum, const ubyte *buf)
 	if (MarkerObject[(pnum*2)+mesnum] !=object_none && Objects[MarkerObject[(pnum*2)+mesnum]].type!=OBJ_NONE && MarkerObject[(pnum*2)+mesnum] !=0)
 		obj_delete(MarkerObject[(pnum*2)+mesnum]);
 
-	MarkerObject[(pnum*2)+mesnum] = drop_marker_object(&position,Objects[Players[pnum].objnum].segnum,&Objects[Players[pnum].objnum].orient,(pnum*2)+mesnum);
+	MarkerObject[(pnum*2)+mesnum] = drop_marker_object(position,Objects[Players[pnum].objnum].segnum,Objects[Players[pnum].objnum].orient,(pnum*2)+mesnum);
 }
 #endif
 
diff --git a/similar/main/object.cpp b/similar/main/object.cpp
index eb03056da..8c05fce11 100644
--- a/similar/main/object.cpp
+++ b/similar/main/object.cpp
@@ -2103,10 +2103,10 @@ void obj_detach_all(const vobjptr_t parent)
 
 #if defined(DXX_BUILD_DESCENT_II)
 //creates a marker object in the world.  returns the object number
-objnum_t drop_marker_object(vms_vector *pos,segnum_t segnum,vms_matrix *orient, int marker_num)
+objnum_t drop_marker_object(const vms_vector &pos,segnum_t segnum,const vms_matrix &orient, int marker_num)
 {
 	Assert(Marker_model_num != -1);
-	auto obj = obj_create(OBJ_MARKER, marker_num, segnum, *pos, orient, Polygon_models[Marker_model_num].rad, CT_NONE, MT_NONE, RT_POLYOBJ);
+	auto obj = obj_create(OBJ_MARKER, marker_num, segnum, pos, &orient, Polygon_models[Marker_model_num].rad, CT_NONE, MT_NONE, RT_POLYOBJ);
 	if (obj != object_none) {
 		obj->rtype.pobj_info.model_num = Marker_model_num;