Codechange: Use a SmallVec for the animated tile list instead of replicating most of the logic.

4 files changed, 39 insertions, 70 deletions

diff --git a/src/animated_tile.cpp b/src/animated_tile.cpp
index 78dda8b3b..796c5f5e0 100644
--- a/src/animated_tile.cpp
+++ b/src/animated_tile.cpp
@@ -11,17 +11,14 @@
 
 #include "stdafx.h"
 #include "core/alloc_func.hpp"
+#include "core/smallvec_type.hpp"
 #include "tile_cmd.h"
 #include "viewport_func.h"
 
 #include "safeguards.h"
 
 /** The table/list with animated tiles. */
-TileIndex *_animated_tile_list = NULL;
-/** The number of animated tiles in the current state. */
-uint _animated_tile_count = 0;
-/** The number of slots for animated tiles allocated currently. */
-uint _animated_tile_allocated = 0;
+SmallVector<TileIndex, 256> _animated_tiles;
 
 /**
  * Removes the given tile from the animated tile table.
@@ -29,17 +26,11 @@ uint _animated_tile_allocated = 0;
  */
 void DeleteAnimatedTile(TileIndex tile)
 {
-	for (TileIndex *ti = _animated_tile_list; ti < _animated_tile_list + _animated_tile_count; ti++) {
-		if (tile == *ti) {
-			/* Remove the hole
-			 * The order of the remaining elements must stay the same, otherwise the animation loop
-			 * may miss a tile; that's why we must use memmove instead of just moving the last element.
-			 */
-			memmove(ti, ti + 1, (_animated_tile_list + _animated_tile_count - (ti + 1)) * sizeof(*ti));
-			_animated_tile_count--;
-			MarkTileDirtyByTile(tile);
-			return;
-		}
+	TileIndex *to_remove = _animated_tiles.Find(tile);
+	if (to_remove != _animated_tiles.End()) {
+		/* The order of the remaining elements must stay the same, otherwise the animation loop may miss a tile. */
+		_animated_tiles.ErasePreservingOrder(to_remove);
+		MarkTileDirtyByTile(tile);
 	}
 }
 
@@ -51,19 +42,7 @@ void DeleteAnimatedTile(TileIndex tile)
 void AddAnimatedTile(TileIndex tile)
 {
 	MarkTileDirtyByTile(tile);
-
-	for (const TileIndex *ti = _animated_tile_list; ti < _animated_tile_list + _animated_tile_count; ti++) {
-		if (tile == *ti) return;
-	}
-
-	/* Table not large enough, so make it larger */
-	if (_animated_tile_count == _animated_tile_allocated) {
-		_animated_tile_allocated *= 2;
-		_animated_tile_list = ReallocT<TileIndex>(_animated_tile_list, _animated_tile_allocated);
-	}
-
-	_animated_tile_list[_animated_tile_count] = tile;
-	_animated_tile_count++;
+	_animated_tiles.Include(tile);
 }
 
 /**
@@ -71,8 +50,8 @@ void AddAnimatedTile(TileIndex tile)
  */
 void AnimateAnimatedTiles()
 {
-	const TileIndex *ti = _animated_tile_list;
-	while (ti < _animated_tile_list + _animated_tile_count) {
+	const TileIndex *ti = _animated_tiles.Begin();
+	while (ti < _animated_tiles.End()) {
 		const TileIndex curr = *ti;
 		AnimateTile(curr);
 		/* During the AnimateTile call, DeleteAnimatedTile could have been called,
@@ -93,7 +72,5 @@ void AnimateAnimatedTiles()
  */
 void InitializeAnimatedTiles()
 {
-	_animated_tile_list = ReallocT<TileIndex>(_animated_tile_list, 256);
-	_animated_tile_count = 0;
-	_animated_tile_allocated = 256;
+	_animated_tiles.Clear();
 }
diff --git a/src/saveload/afterload.cpp b/src/saveload/afterload.cpp
index d5d9bc3a4..f01afb425 100644
--- a/src/saveload/afterload.cpp
+++ b/src/saveload/afterload.cpp
@@ -2157,22 +2157,21 @@ bool AfterLoadGame()
 		/* Animated tiles would sometimes not be actually animated or
 		 * in case of old savegames duplicate. */
 
-		extern TileIndex *_animated_tile_list;
-		extern uint _animated_tile_count;
+		extern SmallVector<TileIndex, 256> _animated_tiles;
 
-		for (uint i = 0; i < _animated_tile_count; /* Nothing */) {
+		for (TileIndex *tile = _animated_tiles.Begin(); tile < _animated_tiles.End(); /* Nothing */) {
 			/* Remove if tile is not animated */
-			bool remove = _tile_type_procs[GetTileType(_animated_tile_list[i])]->animate_tile_proc == NULL;
+			bool remove = _tile_type_procs[GetTileType(*tile)]->animate_tile_proc == NULL;
 
 			/* and remove if duplicate */
-			for (uint j = 0; !remove && j < i; j++) {
-				remove = _animated_tile_list[i] == _animated_tile_list[j];
+			for (TileIndex *j = _animated_tiles.Begin(); !remove && j < tile; j++) {
+				remove = *tile == *j;
 			}
 
 			if (remove) {
-				DeleteAnimatedTile(_animated_tile_list[i]);
+				DeleteAnimatedTile(*tile);
 			} else {
-				i++;
+				tile++;
 			}
 		}
 	}
diff --git a/src/saveload/animated_tile_sl.cpp b/src/saveload/animated_tile_sl.cpp
index 3fc5f6175..2152c42e3 100644
--- a/src/saveload/animated_tile_sl.cpp
+++ b/src/saveload/animated_tile_sl.cpp
@@ -12,22 +12,21 @@
 #include "../stdafx.h"
 #include "../tile_type.h"
 #include "../core/alloc_func.hpp"
+#include "../core/smallvec_type.hpp"
 
 #include "saveload.h"
 
 #include "../safeguards.h"
 
-extern TileIndex *_animated_tile_list;
-extern uint _animated_tile_count;
-extern uint _animated_tile_allocated;
+extern SmallVector<TileIndex, 256> _animated_tiles;
 
 /**
  * Save the ANIT chunk.
  */
 static void Save_ANIT()
 {
-	SlSetLength(_animated_tile_count * sizeof(*_animated_tile_list));
-	SlArray(_animated_tile_list, _animated_tile_count, SLE_UINT32);
+	SlSetLength(_animated_tiles.Length() * sizeof(*_animated_tiles.Begin()));
+	SlArray(_animated_tiles.Begin(), _animated_tiles.Length(), SLE_UINT32);
 }
 
 /**
@@ -38,22 +37,20 @@ static void Load_ANIT()
 	/* Before version 80 we did NOT have a variable length animated tile table */
 	if (IsSavegameVersionBefore(80)) {
 		/* In pre version 6, we has 16bit per tile, now we have 32bit per tile, convert it ;) */
-		SlArray(_animated_tile_list, 256, IsSavegameVersionBefore(6) ? (SLE_FILE_U16 | SLE_VAR_U32) : SLE_UINT32);
+		TileIndex anim_list[256];
+		SlArray(anim_list, 256, IsSavegameVersionBefore(6) ? (SLE_FILE_U16 | SLE_VAR_U32) : SLE_UINT32);
 
-		for (_animated_tile_count = 0; _animated_tile_count < 256; _animated_tile_count++) {
-			if (_animated_tile_list[_animated_tile_count] == 0) break;
+		for (int i = 0; i < 256; i++) {
+			if (anim_list[i] == 0) break;
+			*_animated_tiles.Append() = anim_list[i];
 		}
 		return;
 	}
 
-	_animated_tile_count = (uint)SlGetFieldLength() / sizeof(*_animated_tile_list);
-
-	/* Determine a nice rounded size for the amount of allocated tiles */
-	_animated_tile_allocated = 256;
-	while (_animated_tile_allocated < _animated_tile_count) _animated_tile_allocated *= 2;
-
-	_animated_tile_list = ReallocT<TileIndex>(_animated_tile_list, _animated_tile_allocated);
-	SlArray(_animated_tile_list, _animated_tile_count, SLE_UINT32);
+	uint count = (uint)SlGetFieldLength() / sizeof(*_animated_tiles.Begin());
+	_animated_tiles.Clear();
+	_animated_tiles.Append(count);
+	SlArray(_animated_tiles.Begin(), count, SLE_UINT32);
 }
 
 /**
diff --git a/src/saveload/oldloader_sl.cpp b/src/saveload/oldloader_sl.cpp
index 0c5716681..61a5aa5c6 100644
--- a/src/saveload/oldloader_sl.cpp
+++ b/src/saveload/oldloader_sl.cpp
@@ -28,6 +28,7 @@
 #include "../engine_func.h"
 #include "../company_base.h"
 #include "../disaster_vehicle.h"
+#include "../core/smallvec_type.hpp"
 #include "saveload_internal.h"
 #include "oldloader.h"
 
@@ -490,8 +491,7 @@ static inline uint RemapOrderIndex(uint x)
 	return _savegame_type == SGT_TTO ? (x - 0x1AC4) / 2 : (x - 0x1C18) / 2;
 }
 
-extern TileIndex *_animated_tile_list;
-extern uint _animated_tile_count;
+extern SmallVector<TileIndex, 256> _animated_tiles;
 extern char *_old_name_array;
 
 static uint32 _old_town_index;
@@ -640,22 +640,18 @@ static bool LoadOldOrder(LoadgameState *ls, int num)
 
 static bool LoadOldAnimTileList(LoadgameState *ls, int num)
 {
-	/* This is slightly hackish - we must load a chunk into an array whose
-	 * address isn't static, but instead pointed to by _animated_tile_list.
-	 * To achieve that, create an OldChunks list on the stack on the fly.
-	 * The list cannot be static because the value of _animated_tile_list
-	 * can change between calls. */
-
+	TileIndex anim_list[256];
 	const OldChunks anim_chunk[] = {
-		OCL_VAR (   OC_TILE, 256, _animated_tile_list ),
+		OCL_VAR (   OC_TILE, 256, anim_list ),
 		OCL_END ()
 	};
 
 	if (!LoadChunk(ls, NULL, anim_chunk)) return false;
 
-	/* Update the animated tile counter by counting till the first zero in the array */
-	for (_animated_tile_count = 0; _animated_tile_count < 256; _animated_tile_count++) {
-		if (_animated_tile_list[_animated_tile_count] == 0) break;
+	/* The first zero in the loaded array indicates the end of the list. */
+	for (int i = 0; i < 256; i++) {
+		if (anim_list[i] == 0) break;
+		*_animated_tiles.Append() = anim_list[i];
 	}
 
 	return true;