StreamPeerGZIP in Godot – Complete Guide

Understanding data compression, especially in game development, isn’t just about making files smaller—it’s about improving your game’s performance, reducing latency, and ultimately enhancing the player experience. That’s where a class like StreamPeerGZIP in Godot 4 comes into play.

As we dive deeper into the world of Godot Engine and explore the capabilities of the StreamPeerGZIP class, you will begin to recognize the profound impact it can have on your projects. Whether you’re a budding game developer or a seasoned programmer, understanding the mechanics of real-time data compression can be a game-changer—quite literally.

What is StreamPeerGZIP?

The StreamPeerGZIP class is a specialized tool within Godot Engine—a powerful and open-source game engine favored for its flexibility and ease of use. StreamPeerGZIP extends the functionality of the StreamPeer class, offering developers the ability to handle GZIP and deflate compression and decompression in a streamlined fashion.

What is it for?

There are numerous scenarios where real-time data compression becomes invaluable:

  • Saving on memory by compressing game assets
  • Decreasing load times and bandwidth usage by compressing network data
  • Streamlining the process of saving and loading game states

The StreamPeerGZIP class is specifically designed to tackle these challenges without the need to load entire assets into memory, making it perfect for handling large files or data streams dynamically.

Why Should I Learn It?

Being able to work with a powerful compression tool like StreamPeerGZIP opens up a myriad of possibilities:

  • It equips you with the knowledge to optimize performance efficiently.
  • It enhances your capacity to create more complex games without worrying about hardware limitations.
  • It makes your games more accessible by improving their network efficiency, crucial for players with limited bandwidth.

By mastering StreamPeerGZIP, you’ll add a highly valuable skill to your repertoire—one that can significantly impact the quality and reach of your games. Let’s step into the world of data compression with Godot and discover how you can compress and decompress data on the fly within your games.

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Initializing StreamPeerGZIP for Compression

To begin with StreamPeerGZIP, it’s essential to first instantiate the object. Then you’ll be able to compress data by writing to the stream.

var gzip =

Once the StreamPeerGZIP object is created, prepare a packet of data to compress. This data should be array of bytes. Below is an example of how to convert a string into a bytes array:

var data_to_compress = "Hello, World!".to_utf8()

Now let’s compress the data. We will write the byte array to the StreamPeerGZIP object and then flush the stream to ensure all data is compressed.


The `begin_compression()` method initializes the compression process. Remember that `put_data()` is used to write data into the gzip stream, and `flush()` is required to complete the compression operation.

Reading Compressed Data

After compression, you can read the compressed data back to verify the process or to send it over a network.

First, set up a buffer that will hold the compressed data and read it from the StreamPeerGZIP object:

var buffer = PoolByteArray()


This buffer now contains the compressed representation of “Hello, World!” which you can store or send over the network efficiently.

Initializing StreamPeerGZIP for Decompression

For decompressing data, you will initialize StreamPeerGZIP in a similar manner as for compression:

var gzip =

To decompress, feed the compressed data back to the StreamPeerGZIP object by writing it to the stream:


The method `begin_decompression()` prepares the object to decompress data, while `put_data()` is used to provide the compressed data.

Extracting Original Data from Stream

Following the decompression initiation, extract the decompressed data step-by-step or all at once, ensuring the buffer is adequately sized to hold the decompressed data.

// Find out how many bytes are pending for reading
var decompressed_size = gzip.get_available_bytes()

// Resize buffer to accommodate decompressed data
var decompressed_buffer = PoolByteArray()

// Read the decompressed data into buffer

Lastly, to convert the byte array back to a string:

var original_data = decompressed_buffer.get_string_from_utf8()

To confirm that the process is successful, you can print out ‘original_data,’ which should output “Hello, World!” if the decompression is correctly done. This demonstrates a full cycle of compressing and decompressing data using StreamPeerGZIP in Godot 4.Continuing from where we left off, you now have the basic understanding of how to compress and decompress data using StreamPeerGZIP. Let’s dive into more advanced operations and handling, which will be particularly useful for developing complex games.

Working with Files

Often in game development, you’ll need to compress or decompress files. StreamPeerGZIP can be used in tandem with the File class for these operations.

Let’s take a look at how you can compress a text file using the File and StreamPeerGZIP classes:

var file =
var gzip ="user://my_file.txt", File.READ)
var data = file.get_buffer(file.get_len())


var compressed_data = PoolByteArray()

// Now you can save compressed_data to a file

Remember to replace “user://my_file.txt” with the path to the actual file you wish to compress. The compressed data can then be written back to another file for storage.

Decompressing Files

To decompress a file you’ve previously compressed, follow the reverse process:

var compressed_file =
var gzip ="user://my_compressed_file.gz", File.READ)
var compressed_data = compressed_file.get_buffer(compressed_file.get_len())


var original_data = PoolByteArray()

// You can now write original_data back to a file

Ensure that the file paths and buffers are adequately managed based on where and how the compressed data is stored.

Error Handling

Error handling is crucial in any input/output operations. StreamPeerGZIP, like other I/O operations in Godot, might encounter errors during compression or decompression.

Here are some basic error checking methods you could integrate:

if gzip.get_status() != StreamPeerGZIP.STATUS_OK:
    print("An error occurred during compression/decompression.")

You can implement similar checks immediately after compression and decompression operations to make sure that everything proceeded without any problems.

Streaming Data

In a multiplayer game setting, you may want to stream compressed data in real-time. You can compress the data as you receive it, as shown in the following example:

var network_peer =
# Assume network_peer is already connected and properly set up
var gzip =

while network_peer.get_available_packet_count() > 0:
    var pkt = network_peer.get_packet()

    # Compressed data can now be sent back or stored

This example assumes that your `network_peer` is already set up and connected to a network. As packets are received, they are compressed and then could be sent to other peers or saved to a file.

Through these examples, you can see the versatility of StreamPeerGZIP in handling both file-based and streaming data compression tasks. This knowledge is not only essential but broadens the technical capacity you bring to any Godot project. Remember, optimizing your game’s data footprint can have profound impacts on performance, making StreamPeerGZIP a powerful ally in your development toolkit.When dealing with StreamPeerGZIP in Godot, it’s also important to understand how to efficiently integrate these operations into the game loop and manage the data flow. The following are advanced code examples and insights to further explore the power of StreamPeerGZIP in your projects.

Asynchronous Compression

One of the modern game development practices in Godot is using coroutines with the `yield` keyword, which allows you to perform tasks like compression without blocking the main game thread. This is critical for maintaining smooth gameplay, especially when dealing with large amounts of data that need to be compressed or decompressed.

As an example, here’s how you might implement asynchronous compression:

var gzip =

func _async_compress(data):
    yield(get_tree(), "idle_frame") # Wait for the next frame
    return _get_compressed_data()

func _get_compressed_data():
    var buffer = PoolByteArray()
    return buffer

func _some_function_calling_compress():
    var data = "Data to compress".to_utf8()
    var compressed_data = yield(_async_compress(data), "completed")

This example uses a coroutine to compress data asynchronously, which prevents the game from freezing or stuttering during the compression process.

Custom Streams and GZIP

Godot’s StreamPeerGZIP can also be used in combination with custom stream objects. For instance, if you have a custom PacketStream class for networking, you might want to compress data before sending it through the custom stream:

var custom_stream = # Custom class instance
var gzip =

func _compress_and_send(data):
    var compressed_data = yield(_async_compress(data), "completed")

This efficiently combines custom functionality with StreamPeerGZIP, allowing for a modular approach to game design.

Chunked Compression

There might be situations where the data is too large to compress in one go, or streaming it is more efficient. You can implement chunked compression by breaking the data into smaller parts and passing them through the compression stream one at a time:

func _compress_data_in_chunks(data, chunk_size):
    var gzip =

    for i in range(0, data.size(), chunk_size):
        var chunk = data.subarray(i, i + chunk_size)
        yield(get_tree(), "idle_frame") # Give time back to the engine.

    return _get_compressed_data()

This method allows the game to handle other tasks between compression chunks, preventing long freezes during heavy operations.

Error Handling in Asynchronous Tasks

As with any asynchronous operation, you need to be aware of potential errors that may occur during the processes. You can handle these in your coroutines as well:

func _async_compress(data):
    yield(get_tree(), "idle_frame") # Wait for the next frame

    if gzip.get_status() != StreamPeerGZIP.STATUS_OK:
        push_error("Compression error: " + str(gzip.get_status()))
        return null
    return _get_compressed_data()

In this modified version of the asynchronous compression function, if an error is detected after compression, it is reported, and the function returns null, indicating the compression failed.

Decompression on Demand

Sometimes, you may not need the entire decompressed data at once. On demand decompression can save memory and improve performance:

func _decompress_chunk(gzip_stream, data_size):
    var chunk = PoolByteArray()
    var bytes_read = gzip_stream.get_partial_data(chunk)
    if bytes_read != data_size:
        push_error("Decompression error: Incomplete data read.")
        return null
    return chunk

func _use_decompressed_data():
    var compressed_data = get_compressed_data_somehow()
    var gzip =
    var decompressed_chunk = _decompress_chunk(gzip, 1024) # Decompress first 1024 bytes

    if decompressed_chunk:

These examples highlight the advanced use of StreamPeerGZIP in various scenarios, demonstrating its adaptability and power in optimizing game performance. Each snippet is a testament to why it is crucial to be proficient with tools like StreamPeerGZIP when working with Godot. Whether you’re aiming for peak performance in your game or making your game functionalities as seamless as possible, a deep understanding of these concepts will undoubtedly elevate your game development skills.

Continuing Your Game Development Journey with Godot

Diving into data compression with StreamPeerGZIP is just the beginning of what you can achieve with Godot Engine. As you continue to explore and master new techniques, your ability to create optimized and engaging games will grow immensely. That’s why we encourage you to keep learning and expanding your skill set.

To guide you further on your journey, our Godot Game Development Mini-Degree is a comprehensive pathway that can take you from beginner to professional. This self-paced series of courses covers a wide range of essential topics, from GDScript programming and asset utilization to creating detailed UI systems and mastering gameplay mechanics across various game genres.

Whether you’re a newcomer or someone who has already gotten their feet wet, our curriculum is designed to help you build on your current knowledge. Plus, with project-based learning and quizzes, you’ll have plenty of opportunities to apply what you learn and earn certificates that showcase your progress.

Moreover, if you’re interested in exploring an even broader collection of courses related to this powerful game engine, visit our full range of Godot courses. No matter where you are in your development journey, our resources are here to help you succeed, providing the skills you need to make a mark in the game development industry. So, keep coding, keep creating, and most importantly—keep enjoying the process!


Understanding and utilizing StreamPeerGZIP within Godot 4 is a testament to your dedication to crafting great gaming experiences. Data compression is not just a technical necessity—it’s a craft that enhances every aspect of gameplay, from load times to network efficiency. As you master such powerful tools, you’re not just learning; you’re shaping entire worlds that can captivate and mesmerize players with seamless performance. Keep pushing the boundaries of what you can achieve with data in your games, and you’ll find yourself among the ranks of the most skilled and innovative game developers.

Don’t stop here—take your skills to the next level with our Godot Game Development Mini-Degree. With a mountain of resources at your fingertips, you are sure to find the inspiration you need to transform your passion for game development into reality. Embrace the challenge, join our community of learners, and start creating the games that you’ve always dreamed of.

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