(svn r2080) - Fix: [OldAI] p->ai.state_counter was uint16 but could hold a tile index, therefore overflowing - changed that to uint32 and bumped the savegame revision to 32. It *MIGHT* close bug 1151374 - it certainly caused AI to stop building anything sometimes.

- While at it, use TileIndex as the tile index type in AiRemovePlayerRailOrRoad() and AiStateRemoveTrack().
- Make the number of tiles scanned 4*MapSizeX() instead of 1000. It *MIGHT* close bug 1116614.

ai.c

@@ -3640,7 +3640,7 @@ static void AiStateRemoveStation(Player *p)
 
 }
 
-static void AiRemovePlayerRailOrRoad(Player *p, uint tile)
+static void AiRemovePlayerRailOrRoad(Player *p, TileIndex tile)
 {
 	byte m5;
 
@@ -3758,10 +3758,11 @@ pos_3:
 
 static void AiStateRemoveTrack(Player *p)
 {
-	int num = 1000;
+	/* Was 1000 for standard 8x8 maps. */
+	int num = MapSizeX() * 4;
 
 	do {
-		uint tile = ++p->ai.state_counter;
+		TileIndex tile = ++p->ai.state_counter;
 
 		// Iterated all tiles?
 		if (tile >= MapSize()) {

player.h

@@ -27,7 +27,7 @@ typedef struct AiBuildRec {
 typedef struct PlayerAI {
 	byte state;
 	byte tick; // Used to determine how often to move
-	uint16 state_counter;
+	uint32 state_counter; // Can hold tile index!
 	uint16 timeout_counter;
 
 	byte state_mode;

players.c

@@ -974,7 +974,8 @@ static const byte _player_economy_desc[] = {
 static const byte _player_ai_desc[] = {
 	SLE_VAR(PlayerAI,state,							SLE_UINT8),
 	SLE_VAR(PlayerAI,tick,							SLE_UINT8),
-	SLE_VAR(PlayerAI,state_counter,			SLE_UINT16),
+	SLE_CONDVAR(PlayerAI,state_counter, SLE_FILE_U16 | SLE_VAR_U32, 0, 12),
+	SLE_CONDVAR(PlayerAI,state_counter, SLE_UINT32, 13, 255),
 	SLE_VAR(PlayerAI,timeout_counter,		SLE_UINT16),
 
 	SLE_VAR(PlayerAI,state_mode,				SLE_UINT8),

saveload.c

@@ -8,7 +8,7 @@
 #include "saveload.h"
 
 enum {
-	SAVEGAME_MAJOR_VERSION = 0xC,
+	SAVEGAME_MAJOR_VERSION = 13,
 	SAVEGAME_MINOR_VERSION = 0x1,
 
 	SAVEGAME_LOADABLE_VERSION = (SAVEGAME_MAJOR_VERSION << 8) + SAVEGAME_MINOR_VERSION