diff options
| -rw-r--r-- | src/texteff.cpp | 23 |
1 files changed, 19 insertions, 4 deletions
diff --git a/src/texteff.cpp b/src/texteff.cpp index c376e42b4..f42a650e4 100644 --- a/src/texteff.cpp +++ b/src/texteff.cpp @@ -435,8 +435,11 @@ void DeleteAnimatedTile(TileIndex tile) { for (TileIndex *ti = _animated_tile_list; ti < _animated_tile_list + _animated_tile_count; ti++) { if (tile == *ti) { - /* Remove the hole */ - *ti = _animated_tile_list[_animated_tile_count - 1]; + /* 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; @@ -472,8 +475,20 @@ void AddAnimatedTile(TileIndex tile) */ void AnimateAnimatedTiles() { - for (const TileIndex *ti = _animated_tile_list; ti < _animated_tile_list + _animated_tile_count; ti++) { - AnimateTile(*ti); + const TileIndex *ti = _animated_tile_list; + while (ti < _animated_tile_list + _animated_tile_count) { + const TileIndex curr = *ti; + AnimateTile(curr); + /* During the AnimateTile call, DeleteAnimatedTile could have been called, + * deleting an element we've already processed and pushing the rest one + * slot to the left. We can detect this by checking whether the index + * in the current slot has changed - if it has, an element has been deleted, + * and we should process the current slot again instead of going forward. + * NOTE: this will still break if more than one animated tile is being + * deleted during the same AnimateTile call, but no code seems to + * be doing this anyway. + */ + if (*ti == curr) ++ti; } } |