What is an MCA file?
The Minecraft Anvil region file format is a data storage format that is used to store terrain chunks of a Minecraft World in the popular video game Minecraft. Minecraft world consists regions, where each region is divided into chunks. MCA file format allows for the efficient storage of large amounts of game data, such as the location of blocks and entities in a particular chunk of the game world. MCA files need to be combined with other MCA files to generate a whole world.
In addition to storing game data, the Anvil region file format also includes support for various other data types, such as player data and metadata. This allows for the efficient storage of all of the information needed to fully recreate a particular chunk of the game world, including the location of blocks, entities, and other game objects.
MCA File Format - More Information
The Anvil region file format is a variant of the NBT (Named Binary Tag) format, which is a hierarchical tree-like structure for storing data in a binary file. This allows for the efficient storage of complex data structures in a compact and easily-readable format.
Chunks in MCA File
In Minecraft, a chunk is a 16x16x16 block area of the game world that is loaded into memory and rendered on the player’s screen. The Anvil region file format stores all of the data for a particular chunk in a single file, which can then be quickly loaded into memory when needed. This allows for efficient storage and quick access to the game data, which is important for ensuring a smooth and seamless gaming experience.
Small MCA File Size
One of the key features of the Anvil region file format is its use of compression. This allows for the efficient storage of large amounts of data, without sacrificing the quality of the data or the speed at which it can be accessed. This is accomplished using a variety of techniques, such as gzip compression and chunk data compression.
The compressed file format of MCA files makes it an important part of the game’s data storage and management system. Its efficient use of compression and support for various data types allows for the efficient storage and quick access to the game data, ensuring a smooth and seamless gaming experience for players.
MCA File Format Structure
The internal file format structure of MCA files consists of a:
- Header, and a
- Payload
MCA Header
The header of an MCA region file begins with an 8KiB header that is split into two 4KiB tables. The first table contains the offsets of chunks in the region file itself, while the second table provides timestamps for the last updates of these chunks.
MCA Payload
MCA Payload consists of chunks, where each chunk data begins with a (big-endian) four-byte length field. This field indicates the exact length of the remaining chunk data in bytes. The last chunk’s data is padded to be a multiple-of-4096B in length. Files where last chunk is not padded is not accepted by Minecraft.
How to Open MCA Files
You can open and edit MCA files using MCEdit program, which is a free, open-source editor for Minecraft. You can download MCEdit from the official website and use it to open and view the contents of your Anvil region file.
Once you have MCEdit installed, you can open your Anvil region file by following these steps:
Start MCEdit and click on the “Open” button in the top-left corner of the window.
In the “Open World” dialog box, navigate to the location of your Anvil region file and select it.
Click the “Open” button to open the file in MCEdit.
MCEdit will load the file and display its contents in the main window. You can then use the tools and features in MCEdit to view, edit, and extract data from the Anvil region file.
