VideoStreamPlayback in Godot – Complete Guide

Are you ready to dive into the fascinating world of digital video within games and applications? Today, we will be exploring the VideoStreamPlayback class in Godot 4, a powerful game development engine widely used by hobbyists and professionals alike. Understanding how video playback works in Godot can add a rich layer of media to your projects, making them stand out with engaging cutscenes, instructional content, or immersive environments. Join us as we decode the intricacies of managing video playback state, embedding media content in your games, and providing an enhanced user experience.

What Is VideoStreamPlayback?

VideoStreamPlayback is an internal class within the Godot engine that is primarily used by the VideoStreamPlayer. It’s designed to handle the state and control of video playback in your game or application. Essentially, VideoStreamPlayback forms the backbone of how videos are managed, played, paused, or stopped, and it also handles audio functionalities associated with the video file.

What Is It For?

This class has a variety of methods that allow you to embed video within your Godot projects. For example, it allows you to query the number of audio channels, fetch the length and playback position of a video, or retrieve the texture where the current video frame is drawn. It’s for anyone aiming to add multimedia to their games, whether that’s a simple background video, a complex interactive cutscene, or an instructional video stream within an educational game.

Why Should I Learn It?

Learning about VideoStreamPlayback in Godot 4 can significantly expand your skillset and capabilities as a game developer. Video integration is key to impacting storytelling, enhancing player engagement, and adding a professional touch to your work. It enables you to create more dynamic and multimedia-rich experiences – all of which are in high demand in today’s game industry. Plus, with Godot’s open-source nature, mastering this tool can open opportunities both in developing your own projects and contributing to the community.

CTA Small Image
FREE COURSES AT ZENVA
LEARN GAME DEVELOPMENT, PYTHON AND MORE
ACCESS FOR FREE
AVAILABLE FOR A LIMITED TIME ONLY

Setting Up VideoStreamPlayer

Before we get to manipulating videos with the VideoStreamPlayback class, you need to understand how to set up a VideoStreamPlayer node in your project. Below is the basic setup to get a video playing in Godot.

First, add a VideoStreamPlayer node to your scene tree.

var video_player = VideoStreamPlayer.new()
add_child(video_player)

Next, load your video file onto the VideoStreamPlayer. Ensure your video file is in the .webm or .ogv format as these are supported by Godot.

var video_stream = load("res://path_to_your_video_file.webm")
video_player.stream = video_stream

Finally, play the video.

video_player.play()

Now, your video should be visible in the game window when you run the scene.

Controlling Playback

To give users control over video playback, let’s interact with the VideoStreamPlayer node’s playback state. We can start by creating functions for play, pause, and stop actions.

Here’s how to play and pause a video.

func _play_video():
    if video_player.is_playing():
        video_player.stop()
    video_player.play()

func _pause_video():
    if video_player.is_playing():
        video_player.stop()
        video_player.stream.playback_position = 0

To stop the video playback:

func _stop_video():
    video_player.stop()

Seeking Through a Video

Sometimes, you might want to let the user to skip through the video. To implement seeking functionality, we need to jump to different times in the playback.

Here’s how you can seek to a specific point in the video. This example seeks to 10 seconds into the video.

func _seek_video_to_position(pos):
    video_player.stream.playback_position = pos

If you want to fast forward or rewind by a certain amount of time, here’s how you could do it.

func _fast_forward(seconds):
    var new_position = video_player.stream.playback_position + seconds
    video_player.stream.playback_position = new_position.clamp(0, video_player.stream.get_length())

func _rewind(seconds):
    var new_position = video_player.stream.playback_position - seconds
    video_player.stream.playback_position = new_position.clamp(0, video_player.stream.get_length())

Monitoring Playback Progress

To provide feedback to the user, such as updating a UI element with the video’s progress, you’ll need to retrieve the current playback position.

Here is a simple function to update a progress bar as the video plays.

func _update_progress_bar(progress_bar):
    var video_length = video_player.stream.get_length()
    var current_position = video_player.stream.playback_position
    progress_bar.value = (current_position / video_length) * 100

Remember to call this function at regular intervals, possibly using Godot’s _process method, to keep the progress bar in sync with the video being played.

With these basics, you now possess the fundamental skills for incorporating video into your Godot projects! In our next chapter, we’ll delve deeper and cover how to respond to video playback events, deal with audio tracks, and manage looping videos. Stay tuned as we continue enriching your projects with dynamic media content.Now, we are going to explore more advanced features of video playback in Godot, such as responding to playback events, working with audio tracks, and looping videos. These functionalities will allow you to create an even more interactive and seamless multimedia experience in your games or applications.

Responding to Playback Events

Responding to events like the video finishing can inform players or trigger other parts of your game. Connect your VideoStreamPlayer’s “finished” signal to a function:

func _ready():
    video_player.connect("finished", self, "_on_video_finished")

func _on_video_finished():
    print("Video has finished playing.")
    # You can also trigger other actions here, like transitioning to another scene.

Managing Audio Tracks

If your video has multiple audio tracks, you can switch between them. Here’s how to change the audio track to the second one:

func _set_audio_track(track_idx):
    video_player.stream.audio_track = track_idx

Make sure to call this function with the correct index for the audio track you wish to switch to.

Looping Videos

Looping a video is useful for background scenes or continuous animations. To loop a video, you can set the `loop` property of the VideoStreamPlayer:

video_player.stream.loop = true

However, Godot’s VideoStreamPlayer does not have built-in looping functionality for all formats at the time of writing. You might need to manually loop the video by checking for its end:

func _process(delta):
    if video_player.stream.playback_position >= video_player.stream.get_length() - delta:
        video_player.stream.playback_position = 0 # Reset to start
        video_player.play()

Adjusting Playback Speed

To speed up or slow down the video, adjust the `playback_speed` property. Here’s an example of how to set it for double speed and half-speed playback:

func _set_double_speed():
    video_player.stream.playback_speed = 2.0

func _set_half_speed():
    video_player.stream.playback_speed = 0.5

Feel free to set this to any positive float value to control the speed as per your needs.

Remember, when you manipulate the `playback_speed`, you need to consider how it interacts with the audio. High playback speeds may result in unintelligible audio, whereas slow speeds may result in choppy audio.

By now, you should be quite familiar with how to effectively manage video playback within your Godot projects. These tools and commands empower you to integrate high-quality video content in a manner tailored to your game’s specific needs, ensuring a holistic and immersive gaming environment.

Don’t hesitate to experiment with these capabilities to find creative ways to include video elements in your game. Whether as an engaging story element, a tutorial, or just part of the game’s environment, video can significantly enhance the player’s experience. And remember, practice is the key to mastering any new skill—especially when it comes to game development with Godot.

Implementing Custom Playback Controls

Let’s take a step further and develop custom playback controls for your video content. This not only enhances user experience but also gives you full control over the video player interface.

Start by creating functions for muting and changing volume:

func _mute_video():
    video_player.stream.volume_db = -80 # Mute the video by setting volume to a very low dB value

func _unmute_video():
    video_player.stream.volume_db = 0 # Set the volume to the default value

func _set_volume_db(value):
    video_player.stream.volume_db = value # Set volume to a specific dB value

Next, let’s look at toggling between fullscreen and windowed mode for the video player:

func _toggle_fullscreen():
    if OS.window_fullscreen:
        OS.window_fullscreen = false
    else:
        OS.window_fullscreen = true

Note that this toggles the entire window’s fullscreen state. For a game that’s embedded in the viewport, you might need a different approach for resizing the VideoStreamPlayer node.

Syncing Subtitles with Video

Synchronizing subtitles is a critical feature for accessibility and for games with a heavy narrative focus. Godot’s GUI nodes can be used to create subtitles easily.

Here’s a basic way to sync dialogue using a Label node as subtitles:

func _show_subtitle(text):
    $SubtitleLabel.text = text

func _hide_subtitle():
    $SubtitleLabel.text = ""

# You would need to call _show_subtitle() with the appropriate string based on the video's timestamp.

Remember, this is a simplified example. A full implementation would involve loading a subtitle file (like a .srt file) and displaying the correct text at predetermined times.

Adjusting Playback Based on Player Interaction

Sometimes you want the video to react to player interactions. This can be used for, say, a puzzle where a clue is within a video sequence.

Here’s a hypothetical way to skip to parts of a video using player input:

func _input(event):
    if event is InputEventKey and event.pressed:
        match event.scancode:
            KEY_1:
                _seek_video_to_position(10.0) # Skip to 10 seconds
            KEY_2:
                _seek_video_to_position(20.0) # Skip to 20 seconds

This is a simple implementation where pressing ‘1’ or ‘2’ on the keyboard skips the video to 10 or 20 seconds, respectively.

Integrating Video Playback with Game Events

Another powerful aspect is to trigger in-game events based on the playback. For example, initiating a boss fight right after a cutscene:

func _on_video_finished():
    print("Video has finished playing.")
    _start_boss_fight()

func _start_boss_fight():
    # Code to start the boss fight

Or maybe you want to start the video after a certain event, such as the player entering a room:

func _on_player_enter_room():
    video_player.play()

Video playback is not just about playing a media file; it can be synced and integrated within your game logic to elevate the gaming experience.

Using these code snippets, you can begin to see the many ways that the VideoStreamPlayback class can be used to create a rich interactive multimedia experience within Godot. Whether you’re creating tutorials, cutscenes, or interactive video puzzles, the potential is vast. Innovate, experiment, and remember: the only limit is your creativity as you bring your game development projects to life with Godot.

Where to Go Next in Your Game Development Journey

Congratulations on mastering the fundamentals of video integration in Godot! Your journey to becoming a viable game developer doesn’t stop here, though. To further sharpen your skills and dive deeper into the endless possibilities of game creation, we invite you to explore our Godot Game Development Mini-Degree. This comprehensive series will help you build on the knowledge you’ve gained and grow your abilities through practical projects that span both 2D and 3D game development.

Whether you’re just starting out or looking to expand your current skill set, our Mini-Degree offers a structured and engaging pathway to elevate your game development prowess. At Zenva, we aim to empower your learning journey with a treasure trove of courses, perfect for fitting into your busy schedule. Alongside Godot, we also offer a broad collection of Godot courses catering to all aspects of game design and programming. Each step is an opportunity to create, innovate, and maybe one day, revolutionize the gaming industry with your creations.

We are dedicated to providing high-quality content that gears you towards success, allowing you to learn at your own pace and on any device. Choose Zenva as your guide, and let’s continue making incredible games together!

Conclusion

We’ve covered a treasured trove of knowledge on video integration in Godot, giving you the power to bring dynamic video content into the heart of your projects. The journey of a game developer is ever-evolving, with each new skill opening doors to unexplored territories in game design and player engagement. As you continue to harness the capabilities of Godot’s VideoStreamPlayback class, we encourage you to reflect on the limitless opportunities this knowledge presents. Transform your game’s narrative, customize player experience, and continue to surprise your audience with every project.

Remember, learning is a continuous process, and with Zenva’s Godot Game Development Mini-Degree, you’re never alone on this thrilling adventure. It’s time to take your passion to new heights and to infuse your games with the rich, immersive elements they deserve. Let’s keep the momentum going and shape the future of gaming together—one line of code at a time.

FREE COURSES
Python Blog Image

FINAL DAYS: Unlock coding courses in Unity, Godot, Unreal, Python and more.