diff --git a/src/blitter/null.cpp b/src/blitter/null.cpp
index 87b456c4a4..f2e001cce7 100644
--- a/src/blitter/null.cpp
+++ b/src/blitter/null.cpp
@@ -1,5 +1,8 @@
+/* $Id$ */
+
+/** @file null.cpp A blitter that doesn't blit. */
+
 #include "../stdafx.h"
-#include "../variables.h"
 #include "null.hpp"
 
 static FBlitter_Null iFBlitter_Null;
diff --git a/src/cargo_type.h b/src/cargo_type.h
index ca2f4a239f..521ce9b020 100644
--- a/src/cargo_type.h
+++ b/src/cargo_type.h
@@ -1,5 +1,6 @@
 /* $Id$ */
-/** @file openttd.h */
+
+/** @file cargo_type.h Types related to cargos... */
 
 #ifndef CARGO_TYPE_H
 #define CARGO_TYPE_H
diff --git a/src/core/random_func.cpp b/src/core/random_func.cpp
index 8032500404..b0939229ea 100644
--- a/src/core/random_func.cpp
+++ b/src/core/random_func.cpp
@@ -3,10 +3,11 @@
 /** @file random_func.cpp */
 
 #include "../stdafx.h"
-#include "../variables.h"
 #include "random_func.hpp"
 #include "bitmath_func.hpp"
 
+uint32 _random_seeds[2][2];
+
 uint32 InteractiveRandom()
 {
 	const uint32 s = _random_seeds[1][0];
diff --git a/src/core/random_func.hpp b/src/core/random_func.hpp
index 607d802a88..b0ea5b2b97 100644
--- a/src/core/random_func.hpp
+++ b/src/core/random_func.hpp
@@ -100,4 +100,6 @@ static inline bool Chance16R(const uint a, const uint b, uint32 &r)
 	return Chance16I(a, b, r);
 }
 
+extern uint32 _random_seeds[2][2];
+
 #endif /* RANDOM_FUNC_HPP */
diff --git a/src/functions.h b/src/functions.h
index 3afdcebbf2..4740089033 100644
--- a/src/functions.h
+++ b/src/functions.h
@@ -7,7 +7,6 @@
 
 #include "core/random_func.hpp"
 #include "command_type.h"
-#include "openttd.h"
 #include "tile_cmd.h"
 
 /* clear_land.cpp */
diff --git a/src/genworld.cpp b/src/genworld.cpp
index b374fdee4b..7fc1cfd92d 100644
--- a/src/genworld.cpp
+++ b/src/genworld.cpp
@@ -20,6 +20,7 @@
 #include "viewport.h"
 #include "map_func.h"
 #include "date_func.h"
+#include "core/random_func.hpp"
 
 void GenerateClearTile();
 void GenerateIndustries();
diff --git a/src/newgrf_config.h b/src/newgrf_config.h
index b5234723e0..6042d954ab 100644
--- a/src/newgrf_config.h
+++ b/src/newgrf_config.h
@@ -5,7 +5,7 @@
 #ifndef NEWGRF_CONFIG_H
 #define NEWGRF_CONFIG_H
 
-#include "openttd.h"
+#include "strings_type.h"
 
 /* GRF config bit flags */
 enum GCF_Flags {
diff --git a/src/npf.h b/src/npf.h
index 19c0f41b21..aaab48a186 100644
--- a/src/npf.h
+++ b/src/npf.h
@@ -5,7 +5,6 @@
 #ifndef NPF_H
 #define NPF_H
 
-#include "openttd.h"
 #include "aystar.h"
 #include "station.h"
 #include "vehicle_type.h"
diff --git a/src/pathfind.h b/src/pathfind.h
index 91dd7be6f3..f089e8e165 100644
--- a/src/pathfind.h
+++ b/src/pathfind.h
@@ -6,7 +6,6 @@
 #define PATHFIND_H
 
 #include "direction_type.h"
-#include "openttd.h"
 
 enum {
 	STR_FACTOR  = 2,
diff --git a/src/spriteloader/png.cpp b/src/spriteloader/png.cpp
index e40fb39b7d..83f7bdd77a 100644
--- a/src/spriteloader/png.cpp
+++ b/src/spriteloader/png.cpp
@@ -7,7 +7,6 @@
 #include "../stdafx.h"
 #include "../gfx_func.h"
 #include "../fileio.h"
-#include "../variables.h"
 #include "../debug.h"
 #include "../core/alloc_func.hpp"
 #include "../core/endian_func.hpp"
diff --git a/src/tunnelbridge_map.h b/src/tunnelbridge_map.h
index b2beb57689..e9cbe0945a 100644
--- a/src/tunnelbridge_map.h
+++ b/src/tunnelbridge_map.h
@@ -8,7 +8,6 @@
 #include "direction_func.h"
 #include "core/bitmath_func.hpp"
 #include "tile_map.h"
-#include "openttd.h"
 
 
 /**
diff --git a/src/variables.h b/src/variables.h
index e4af2dcbcf..b671fee3d8 100644
--- a/src/variables.h
+++ b/src/variables.h
@@ -6,7 +6,6 @@
 #define VARIABLES_H
 
 #include "yapf/yapf_settings.h"
-#include "openttd.h"
 #include "tile_type.h"
 #include "strings_type.h"
 #include "date_type.h"
@@ -51,8 +50,6 @@ VARDEF uint16 _disaster_delay;
  *  tick handler. */
 VARDEF uint16 _station_tick_ctr;
 
-VARDEF uint32 _random_seeds[2][2];
-
 /* Iterator through all towns in OnTick_Town */
 VARDEF uint32 _cur_town_ctr;
 /* Frequency iterator at the same place */