diff --git a/src/spritecache.h b/src/spritecache.h
--- a/src/spritecache.h
+++ b/src/spritecache.h
@@ -51,7 +51,9 @@ void GfxInitSpriteMem();
 void GfxClearSpriteCache();
 void IncreaseSpriteLRU();
 
-bool LoadNextSprite(int load_index, byte file_index, uint file_sprite_id);
+void ReadGRFSpriteOffsets(byte container_version);
+size_t GetGRFSpriteOffset(uint32 id);
+bool LoadNextSprite(int load_index, byte file_index, uint file_sprite_id, byte container_version);
 bool SkipSpriteData(byte type, uint16 num);
 void DupSprite(SpriteID old_spr, SpriteID new_spr);