diff --git a/common/main/cntrlcen.h b/common/main/cntrlcen.h
index 1fc90585b..899f2db2a 100644
--- a/common/main/cntrlcen.h
+++ b/common/main/cntrlcen.h
@@ -23,11 +23,9 @@ COPYRIGHT 1993-1999 PARALLAX SOFTWARE CORPORATION.  ALL RIGHTS RESERVED.
  *
  */
 
-#ifndef _CNTRLCEN_H
-#define _CNTRLCEN_H
+#pragma once
 
-#include "vecmat.h"
-#include "switch.h"
+#include <physfs.h>
 
 #ifdef __cplusplus
 #include "fwdobject.h"
@@ -48,6 +46,7 @@ struct control_center_triggers : public prohibit_void_ptr<control_center_trigger
 extern control_center_triggers ControlCenterTriggers;
 
 #if defined(DXX_BUILD_DESCENT_I) || defined(DXX_BUILD_DESCENT_II)
+#include "vecmat.h"
 struct reactor {
 #if defined(DXX_BUILD_DESCENT_II)
 	int model_num;
@@ -148,5 +147,3 @@ static inline void control_center_triggers_read(control_center_triggers *cct, PH
 void control_center_triggers_write(const control_center_triggers *cct, PHYSFS_file *fp);
 
 #endif
-
-#endif /* _CNTRLCEN_H */
diff --git a/common/main/fwdobject.h b/common/main/fwdobject.h
index 4452d9feb..2a65e27aa 100644
--- a/common/main/fwdobject.h
+++ b/common/main/fwdobject.h
@@ -13,8 +13,11 @@
 #include "objnum.h"
 #include "segnum.h"
 #include "fwdvalptridx.h"
+#include "maths.h"
 
 struct bitmap_index;
+struct vms_vector;
+struct vms_matrix;
 
 const unsigned MAX_OBJECTS = 350;
 const unsigned MAX_USED_OBJECTS	= MAX_OBJECTS - 20;