richk@10991: /* $Id: animated_tile.cpp 12800 2008-04-20 08:22:59Z rubidium $ */
richk@10991: 
richk@10991: /** @file animated_tile.cpp Everything related to animated tiles. */
richk@10991: 
richk@10991: #include "stdafx.h"
richk@10991: #include "openttd.h"
richk@10991: #include "saveload.h"
richk@10991: #include "landscape.h"
richk@10991: #include "core/alloc_func.hpp"
richk@10991: #include "functions.h"
richk@10991: 
richk@10991: /** The table/list with animated tiles. */
richk@10991: TileIndex *_animated_tile_list = NULL;
richk@10991: /** The number of animated tiles in the current state. */
richk@10991: uint _animated_tile_count = 0;
richk@10991: /** The number of slots for animated tiles allocated currently. */
richk@10991: static uint _animated_tile_allocated = 0;
richk@10991: 
richk@10991: /**
richk@10991:  * Removes the given tile from the animated tile table.
richk@10991:  * @param tile the tile to remove
richk@10991:  */
richk@10991: void DeleteAnimatedTile(TileIndex tile)
richk@10991: {
richk@10991: 	for (TileIndex *ti = _animated_tile_list; ti < _animated_tile_list + _animated_tile_count; ti++) {
richk@10991: 		if (tile == *ti) {
richk@10991: 			/* Remove the hole
richk@10991: 			 * The order of the remaining elements must stay the same, otherwise the animation loop
richk@10991: 			 * may miss a tile; that's why we must use memmove instead of just moving the last element.
richk@10991: 			 */
richk@10991: 			memmove(ti, ti + 1, (_animated_tile_list + _animated_tile_count - (ti + 1)) * sizeof(*ti));
richk@10991: 			_animated_tile_count--;
richk@10991: 			MarkTileDirtyByTile(tile);
richk@10991: 			return;
richk@10991: 		}
richk@10991: 	}
richk@10991: }
richk@10991: 
richk@10991: /**
richk@10991:  * Add the given tile to the animated tile table (if it does not exist
richk@10991:  * on that table yet). Also increases the size of the table if necessary.
richk@10991:  * @param tile the tile to make animated
richk@10991:  */
richk@10991: void AddAnimatedTile(TileIndex tile)
richk@10991: {
richk@10991: 	MarkTileDirtyByTile(tile);
richk@10991: 
richk@10991: 	for (const TileIndex *ti = _animated_tile_list; ti < _animated_tile_list + _animated_tile_count; ti++) {
richk@10991: 		if (tile == *ti) return;
richk@10991: 	}
richk@10991: 
richk@10991: 	/* Table not large enough, so make it larger */
richk@10991: 	if (_animated_tile_count == _animated_tile_allocated) {
richk@10991: 		_animated_tile_allocated *= 2;
richk@10991: 		_animated_tile_list = ReallocT<TileIndex>(_animated_tile_list, _animated_tile_allocated);
richk@10991: 	}
richk@10991: 
richk@10991: 	_animated_tile_list[_animated_tile_count] = tile;
richk@10991: 	_animated_tile_count++;
richk@10991: }
richk@10991: 
richk@10991: /**
richk@10991:  * Animate all tiles in the animated tile list, i.e.\ call AnimateTile on them.
richk@10991:  */
richk@10991: void AnimateAnimatedTiles()
richk@10991: {
richk@10991: 	const TileIndex *ti = _animated_tile_list;
richk@10991: 	while (ti < _animated_tile_list + _animated_tile_count) {
richk@10991: 		const TileIndex curr = *ti;
richk@10991: 		AnimateTile(curr);
richk@10991: 		/* During the AnimateTile call, DeleteAnimatedTile could have been called,
richk@10991: 		 * deleting an element we've already processed and pushing the rest one
richk@10991: 		 * slot to the left. We can detect this by checking whether the index
richk@10991: 		 * in the current slot has changed - if it has, an element has been deleted,
richk@10991: 		 * and we should process the current slot again instead of going forward.
richk@10991: 		 * NOTE: this will still break if more than one animated tile is being
richk@10991: 		 *       deleted during the same AnimateTile call, but no code seems to
richk@10991: 		 *       be doing this anyway.
richk@10991: 		 */
richk@10991: 		if (*ti == curr) ++ti;
richk@10991: 	}
richk@10991: }
richk@10991: 
richk@10991: /**
richk@10991:  * Initialize all animated tile variables to some known begin point
richk@10991:  */
richk@10991: void InitializeAnimatedTiles()
richk@10991: {
richk@10991: 	_animated_tile_list = ReallocT<TileIndex>(_animated_tile_list, 256);
richk@10991: 	_animated_tile_count = 0;
richk@10991: 	_animated_tile_allocated = 256;
richk@10991: }
richk@10991: 
richk@10991: /**
richk@10991:  * Save the ANIT chunk.
richk@10991:  */
richk@10991: static void Save_ANIT()
richk@10991: {
richk@10991: 	SlSetLength(_animated_tile_count * sizeof(*_animated_tile_list));
richk@10991: 	SlArray(_animated_tile_list, _animated_tile_count, SLE_UINT32);
richk@10991: }
richk@10991: 
richk@10991: /**
richk@10991:  * Load the ANIT chunk; the chunk containing the animated tiles.
richk@10991:  */
richk@10991: static void Load_ANIT()
richk@10991: {
richk@10991: 	/* Before version 80 we did NOT have a variable length animated tile table */
richk@10991: 	if (CheckSavegameVersion(80)) {
richk@10991: 		/* In pre version 6, we has 16bit per tile, now we have 32bit per tile, convert it ;) */
richk@10991: 		SlArray(_animated_tile_list, 256, CheckSavegameVersion(6) ? (SLE_FILE_U16 | SLE_VAR_U32) : SLE_UINT32);
richk@10991: 
richk@10991: 		for (_animated_tile_count = 0; _animated_tile_count < 256; _animated_tile_count++) {
richk@10991: 			if (_animated_tile_list[_animated_tile_count] == 0) break;
richk@10991: 		}
richk@10991: 		return;
richk@10991: 	}
richk@10991: 
richk@10991: 	_animated_tile_count = (uint)SlGetFieldLength() / sizeof(*_animated_tile_list);
richk@10991: 
richk@10991: 	/* Determine a nice rounded size for the amount of allocated tiles */
richk@10991: 	_animated_tile_allocated = 256;
richk@10991: 	while (_animated_tile_allocated < _animated_tile_count) _animated_tile_allocated *= 2;
richk@10991: 
richk@10991: 	_animated_tile_list = ReallocT<TileIndex>(_animated_tile_list, _animated_tile_allocated);
richk@10991: 	SlArray(_animated_tile_list, _animated_tile_count, SLE_UINT32);
richk@10991: }
richk@10991: 
richk@10991: /**
richk@10991:  * "Definition" imported by the saveload code to be able to load and save
richk@10991:  * the animated tile table.
richk@10991:  */
richk@10991: extern const ChunkHandler _animated_tile_chunk_handlers[] = {
richk@10991: 	{ 'ANIT', Save_ANIT, Load_ANIT, CH_RIFF | CH_LAST},
richk@10991: };