From 03536a32a189918713ec808bf270d4ad853a7a38 Mon Sep 17 00:00:00 2001
From: tron <tron@openttd.org>
Date: Wed, 8 Mar 2006 08:16:31 +0000
Subject: (svn r3786) More work for DirDiff

---
 aircraft_cmd.c | 9 +++++----
 disaster_cmd.c | 2 +-
 roadveh_cmd.c  | 8 ++++++--
 train_cmd.c    | 9 ++++++---
 4 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/aircraft_cmd.c b/aircraft_cmd.c
index ba1c9ee2b..da812a4bf 100644
--- a/aircraft_cmd.c
+++ b/aircraft_cmd.c
@@ -947,9 +947,6 @@ static bool AircraftController(Vehicle *v)
 	return false;
 }
 
-static const int8 _crashed_aircraft_moddir[4] = {
-	-1,0,0,1
-};
 
 static void HandleCrashedAircraft(Vehicle *v)
 {
@@ -973,7 +970,11 @@ static void HandleCrashedAircraft(Vehicle *v)
 
 	if (v->u.air.crashed_counter < 650) {
 		if (CHANCE16R(1,32,r)) {
-			v->direction = (v->direction + _crashed_aircraft_moddir[GB(r, 16, 2)]) & 7;
+			static const DirDiff delta[] = {
+				DIRDIFF_45LEFT, DIRDIFF_SAME, DIRDIFF_SAME, DIRDIFF_45RIGHT
+			};
+
+			v->direction = ChangeDir(v->direction, delta[GB(r, 16, 2)]);
 			SetAircraftPosition(v, v->x_pos, v->y_pos, v->z_pos);
 			r = Random();
 			CreateEffectVehicleRel(v,
diff --git a/disaster_cmd.c b/disaster_cmd.c
index 61590c47a..d053ff199 100644
--- a/disaster_cmd.c
+++ b/disaster_cmd.c
@@ -665,7 +665,7 @@ static void DisasterTick_5_and_6(Vehicle *v)
 		return;
 	}
 
-	v->direction = (v->direction + (GB(Random(), 0, 1) ? 2 : -2)) & 7;
+	v->direction = ChangeDir(v->direction, GB(Random(), 0, 1) ? DIRDIFF_90RIGHT : DIRDIFF_90LEFT);
 }
 
 
diff --git a/roadveh_cmd.c b/roadveh_cmd.c
index 7a97722ce..6c3d27d69 100644
--- a/roadveh_cmd.c
+++ b/roadveh_cmd.c
@@ -494,9 +494,13 @@ static byte SetRoadVehPosition(Vehicle *v, int x, int y)
 
 static void RoadVehSetRandomDirection(Vehicle *v)
 {
-	static const int8 _turn_prob[4] = { -1, 0, 0, 1 };
+	static const DirDiff delta[] = {
+		DIRDIFF_45LEFT, DIRDIFF_SAME, DIRDIFF_SAME, DIRDIFF_45RIGHT
+	};
+
 	uint32 r = Random();
-	v->direction = (v->direction + _turn_prob[r & 3]) & 7;
+
+	v->direction = ChangeDir(v->direction, delta[r & 3]);
 	BeginVehicleMove(v);
 	UpdateRoadVehDeltaXY(v);
 	v->cur_image = GetRoadVehImage(v, v->direction);
diff --git a/train_cmd.c b/train_cmd.c
index 960af695a..88e8881d2 100644
--- a/train_cmd.c
+++ b/train_cmd.c
@@ -3015,12 +3015,15 @@ static void DeleteLastWagon(Vehicle *v)
 
 static void ChangeTrainDirRandomly(Vehicle *v)
 {
-	static const int8 _random_dir_change[4] = { -1, 0, 0, 1 };
+	static const DirDiff delta[] = {
+		DIRDIFF_45LEFT, DIRDIFF_SAME, DIRDIFF_SAME, DIRDIFF_45RIGHT
+	};
 
 	do {
 		//I need to buffer the train direction
-		if (!(v->u.rail.track & 0x40))
-			v->direction = (v->direction + _random_dir_change[GB(Random(), 0, 2)]) & 7;
+		if (!(v->u.rail.track & 0x40)) {
+			v->direction = ChangeDir(v->direction, delta[GB(Random(), 0, 2)]);
+		}
 		if (!(v->vehstatus & VS_HIDDEN)) {
 			BeginVehicleMove(v);
 			UpdateTrainDeltaXY(v, v->direction);
-- 
cgit v1.2.3-70-g09d2