(svn r12452) -Feature: [NewGRF] Add random action 2 type 84. For vehicles only.

11 files changed, 46 insertions, 2 deletions

diff --git a/src/newgrf.cpp b/src/newgrf.cpp
index 5d405b483..23cf67c14 100644
--- a/src/newgrf.cpp
+++ b/src/newgrf.cpp
@@ -2584,13 +2584,19 @@ static void NewSpriteGroup(byte *buf, int len)
 		/* Randomized Sprite Group */
 		case 0x80: // Self scope
 		case 0x83: // Parent scope
+		case 0x84: // Relative scope
 		{
-			if (!check_length(bufend - buf, 7, "NewSpriteGroup (Randomized) (1)")) return;
+			if (!check_length(bufend - buf, HasBit(type, 2) ? 8 : 7, "NewSpriteGroup (Randomized) (1)")) return;
 
 			group = AllocateSpriteGroup();
 			group->type = SGT_RANDOMIZED;
 			group->g.random.var_scope = HasBit(type, 1) ? VSG_SCOPE_PARENT : VSG_SCOPE_SELF;
 
+			if (HasBit(type, 2) && feature <= GSF_AIRCRAFT) {
+				group->g.random.var_scope = VSG_SCOPE_RELATIVE;
+				group->g.random.count = grf_load_byte(&buf);
+			}
+
 			uint8 triggers = grf_load_byte(&buf);
 			group->g.random.triggers       = GB(triggers, 0, 7);
 			group->g.random.cmp_mode       = HasBit(triggers, 7) ? RSG_CMP_ALL : RSG_CMP_ANY;
diff --git a/src/newgrf_canal.cpp b/src/newgrf_canal.cpp
index df3d7630c..50c60e524 100644
--- a/src/newgrf_canal.cpp
+++ b/src/newgrf_canal.cpp
@@ -85,6 +85,7 @@ static void NewCanalResolver(ResolverObject *res, TileIndex tile)
 	res->last_value      = 0;
 	res->trigger         = 0;
 	res->reseed          = 0;
+	res->count           = 0;
 }
 
 
diff --git a/src/newgrf_cargo.cpp b/src/newgrf_cargo.cpp
index d43f61019..67630ee6d 100644
--- a/src/newgrf_cargo.cpp
+++ b/src/newgrf_cargo.cpp
@@ -64,6 +64,7 @@ static void NewCargoResolver(ResolverObject *res, const CargoSpec *cs)
 	res->last_value      = 0;
 	res->trigger         = 0;
 	res->reseed          = 0;
+	res->count           = 0;
 }
 
 
diff --git a/src/newgrf_engine.cpp b/src/newgrf_engine.cpp
index ef31b976c..f36f3e52a 100644
--- a/src/newgrf_engine.cpp
+++ b/src/newgrf_engine.cpp
@@ -400,7 +400,32 @@ enum {
 /* Vehicle Resolver Functions */
 static inline const Vehicle *GRV(const ResolverObject *object)
 {
-	return object->scope == VSG_SCOPE_SELF ? object->u.vehicle.self : object->u.vehicle.parent;
+	switch (object->scope) {
+		default: NOT_REACHED();
+		case VSG_SCOPE_SELF: return object->u.vehicle.self;
+		case VSG_SCOPE_PARENT: return object->u.vehicle.parent;
+		case VSG_SCOPE_RELATIVE: {
+			const Vehicle *v;
+			switch (GB(object->count, 6, 2)) {
+				default: NOT_REACHED();
+				case 0x00: // count back (away from the engine), starting at this vehicle
+				case 0x01: // count forward (toward the engine), starting at this vehicle
+					v = object->u.vehicle.self;
+					break;
+				case 0x02: // count back, starting at the engine
+					v = object->u.vehicle.parent;
+					break;
+				case 0x03: // count back, starting at the first vehicle in this chain of vehicles with the same ID, as for vehicle variable 41
+					v = object->u.vehicle.parent;
+					while (v != NULL && v->engine_type != object->u.vehicle.self->engine_type) v = v->Next();
+					break;
+			}
+			uint32 count = GB(object->count, 0, 4);
+			if (count == 0) count = GetRegister(0x100);
+			while (v != NULL && count-- != 0) v = (GB(object->count, 6, 2) == 0x01) ? v->Previous() : v->Next();
+			return v;
+		}
+	}
 }
 
 
@@ -816,6 +841,7 @@ static inline void NewVehicleResolver(ResolverObject *res, EngineID engine_type,
 	res->last_value      = 0;
 	res->trigger         = 0;
 	res->reseed          = 0;
+	res->count           = 0;
 }
 
 
diff --git a/src/newgrf_generic.cpp b/src/newgrf_generic.cpp
index 8d515d713..0097979e3 100644
--- a/src/newgrf_generic.cpp
+++ b/src/newgrf_generic.cpp
@@ -125,6 +125,7 @@ static inline void NewGenericResolver(ResolverObject *res)
 	res->last_value      = 0;
 	res->trigger         = 0;
 	res->reseed          = 0;
+	res->count           = 0;
 }
 
 
diff --git a/src/newgrf_house.cpp b/src/newgrf_house.cpp
index 251207c19..e59097f70 100644
--- a/src/newgrf_house.cpp
+++ b/src/newgrf_house.cpp
@@ -291,6 +291,7 @@ static void NewHouseResolver(ResolverObject *res, HouseID house_id, TileIndex ti
 	res->last_value      = 0;
 	res->trigger         = 0;
 	res->reseed          = 0;
+	res->count           = 0;
 }
 
 uint16 GetHouseCallback(CallbackID callback, uint32 param1, uint32 param2, HouseID house_id, Town *town, TileIndex tile)
diff --git a/src/newgrf_industries.cpp b/src/newgrf_industries.cpp
index 618458d6b..d77cfb8a6 100644
--- a/src/newgrf_industries.cpp
+++ b/src/newgrf_industries.cpp
@@ -410,6 +410,7 @@ static void NewIndustryResolver(ResolverObject *res, TileIndex tile, Industry *i
 	res->last_value      = 0;
 	res->trigger         = 0;
 	res->reseed          = 0;
+	res->count           = 0;
 }
 
 uint16 GetIndustryCallback(CallbackID callback, uint32 param1, uint32 param2, Industry *industry, IndustryType type, TileIndex tile)
diff --git a/src/newgrf_industrytiles.cpp b/src/newgrf_industrytiles.cpp
index 4b229f7e3..1303a6460 100644
--- a/src/newgrf_industrytiles.cpp
+++ b/src/newgrf_industrytiles.cpp
@@ -170,6 +170,7 @@ static void NewIndustryTileResolver(ResolverObject *res, IndustryGfx gfx, TileIn
 	res->last_value      = 0;
 	res->trigger         = 0;
 	res->reseed          = 0;
+	res->count           = 0;
 }
 
 void IndustryDrawTileLayout(const TileInfo *ti, const SpriteGroup *group, byte rnd_color, byte stage, IndustryGfx gfx)
diff --git a/src/newgrf_spritegroup.cpp b/src/newgrf_spritegroup.cpp
index 65e8f29e2..a132a0cc6 100644
--- a/src/newgrf_spritegroup.cpp
+++ b/src/newgrf_spritegroup.cpp
@@ -256,6 +256,7 @@ static inline const SpriteGroup *ResolveRandom(const SpriteGroup *group, Resolve
 	byte index;
 
 	object->scope = group->g.random.var_scope;
+	object->count = group->g.random.count;
 
 	if (object->trigger != 0) {
 		/* Handle triggers */
diff --git a/src/newgrf_spritegroup.h b/src/newgrf_spritegroup.h
index 4a3baa0f4..d3fcde0f6 100644
--- a/src/newgrf_spritegroup.h
+++ b/src/newgrf_spritegroup.h
@@ -48,6 +48,8 @@ enum VarSpriteGroupScope {
 	VSG_SCOPE_SELF,
 	/* Engine of consists for vehicles, city for stations. */
 	VSG_SCOPE_PARENT,
+	/* Any vehicle in the consist (vehicles only) */
+	VSG_SCOPE_RELATIVE,
 };
 
 enum DeterministicSpriteGroupSize {
@@ -128,6 +130,7 @@ struct RandomizedSpriteGroup {
 
 	RandomizedSpriteGroupCompareMode cmp_mode; ///< Check for these triggers:
 	byte triggers;
+	byte count;
 
 	byte lowest_randbit; ///< Look for this in the per-object randomized bitmask:
 	byte num_groups; ///< must be power of 2
@@ -201,6 +204,7 @@ struct ResolverObject {
 	bool procedure_call; ///< true if we are currently resolving a var 0x7E procedure result.
 
 	byte trigger;
+	byte count;
 	uint32 last_value;
 	uint32 reseed;
 	VarSpriteGroupScope scope;
diff --git a/src/newgrf_station.cpp b/src/newgrf_station.cpp
index aefef9ed1..5162f6028 100644
--- a/src/newgrf_station.cpp
+++ b/src/newgrf_station.cpp
@@ -571,6 +571,7 @@ static void NewStationResolver(ResolverObject *res, const StationSpec *statspec,
 	res->last_value      = 0;
 	res->trigger         = 0;
 	res->reseed          = 0;
+	res->count           = 0;
 }
 
 static const SpriteGroup *ResolveStation(ResolverObject *object)