Two versions of GB Studio are available for Windows. The Squirrel Installer version just requires you to unzip, double click and then wait a few seconds while the application installs to your C:\ drive. Once installed a shortcut will be added to your desktop automatically and the application will start. The application will be installed to
%LocalAppData%\gb_studio, if you need to install to a different location use the Manual version.
The Manual version is a zip containing the application files, you can unzip this to any location. Once unzipped double click
gb-studio.exe to start.
For macOS unzip the downloaded file and move
GB Studio.app to your Applications folder. Double click to start.
If you're having trouble building or running your game you may also need to install Apple's Command Line Tools by opening
Applications/Terminal.app and entering the following command.
Ubuntu / Debian-based Linux
For Debian-based Linux distros, download the .deb version and run the following commands (Tested on Ubuntu 18.10)
> sudo apt-get update > sudo apt-get install build-essential > sudo dpkg -i gb-studio_1.0.0_amd64.deb > gb-studio
Fedora / RPM-based Linux
For RPM-based Linux distros, download the .rpm version and run the following commands (Tested on Fedora 29)
> sudo yum install libXScrnSaver make lsb > sudo rpm --ignoreos -i gb-studio-1.0.0.x86_64.rpm > gb-studio
When you first open GB Studio you will see the New Project window.
If you have an existing project you can open it from here by clicking Open and navigating to the
Give your project a name to get started (don't worry, you can change this later) and choose a project template. If you're new to GB Studio then I would recommend using the Sample Project template which contains a few example scenes and scripts already set up so you can get a small idea of what's possible. Click Create Project and you'll be taken to the Project Editor.
As soon as you see this screen you can click the Play button in the top right which will just take a few seconds to run the project. After playing the sample project you can try clicking around the editor to see how the project is set up. Select one of the people or signposts and edit the their dialogue using the sidebar on the right then try running the project again, you've just made your very own version of the game! Don't worry if you break anything, you can always make a new project with the sample template later.
When playing your game inside GB Studio use the following keyboard controls:
Up - Up Arrow / W
Down - Down Arrow / S
Left - Left Arrow / A
Right - Right Arrow / D
A - Alt / Z / J
B - Ctrl / K / X
Start - Enter
Select - Shift
New in 1.2.0
You can also control the Play Window using a supported gamepad. If your web browser has gamepad support you can also use it when running a web build.
Navigating The Menus
Much of the functionality of GB Studio is accessible through the menu bar and many of the menu items contain keyboard shortcut labels. Try clicking around on the menus to discover all of the shortcuts but the following are a few you should find useful:
Save Project - Ctrl/Cmd + S
Open Project - Ctrl/Cmd + O
Switch View Mode - Ctrl/Cmd + 1-8
Run Game - Ctrl/Cmd + B
Export ROM file - Ctrl/Cmd + Shift + B
While editing the game world you can use the following keys to quickly manipulate your scenes.
Select Mode - V
Add Actor - A
Add Trigger - T
Add Scene - S
Eraser Mode - E
Collisions Mode - C
Set Player Start Position - P (while hovering over desired location)
Saving and Loading
To save your project select
File > Save from the menu or press Ctrl/Cmd + S. If you try to close a project with unsaved changes GB Studio will warn you giving you a chance to save your project first. On macOS any unsaved changes in your project will be represented by a dot in the window close button.
To load your project again, either use the Open button on the New Project window or select
File > Open from the menu and navigate to your project's folder then select the
The project folder layout and
.gbsproj file is designed to work well with version control systems such as Git with each change by the application taking place on a new line in the data file allowing history to be tracked easily. If you want to use version control on your project you can just create the repository at the project root folder.
It's recommended to ignore the
build folder from your repository using a
.gitignore file or similar.
Each time you save your project the previous version is saved to your project folder with the extension
.gbsproj.bak. If you ever wish to roll back to the previous version in your project you can rename this file to have the extension
.gbsproj and open this file instead.
The Project Editor
The default view for the Project Editor, as shown below, is the Game World. This is where you can create your game by combining scenes, adding actors and triggers then building scripting events to add interactions.
Use the Editor Tools to switch between Select, Add, Erase and Collision Drawing modes.
In the Select mode clicking scenes, actors or triggers causes the Editor Sidebar to show editable fields specific to whatever was selected. Clicking in the background between scenes switches the sidebar back to the Project Editor where you can set the project name and choose the starting scene and position.
The Asset Viewer
Using the Project Navigator you can switch between the available views for your project. If you select Sprites, Backgrounds, UI Elements or Music you will be taken to the asset viewer where you can search and preview the assets available in your game.
See the documentation on Assets for more information on how to add new assets and the different requirements needed.
Adding a Scene
To add a scene to a scene click the + button in the Editor Tools and select Scene from the menu (alternatively press the S key), then click on any empty space in the Project Viewport where you wish to place the scene.
When a scene has been added you can use the Editor Sidebar to give the scene a name and to choose which background image from your project's assets that you want to use. See the documentation for Backgrounds for more information on adding background images.
A scene On Init script can be used to have events run as soon as the scene is loaded. When the scene is selected click the Add Event button in the Editor Sidebar to open the event menu and start building the script.
If any actors in the scene also have On Init scripts they will be executed first.
For more information see the documentation for Scripting.
The player starting position is indicated in the game world view by the icon.
Clicking in the background between scenes switches the sidebar back to the Project Editor where you'll have options to set the player starting scene, position, direction and sprite sheet.
You can also change the player start position by dragging the icon and can even drag between scenes.
Most actor script events can also be applied to the player. In addition you can use Set Player Sprite Sheet event to change the graphics used for the player character mid-game. Changing the sprite sheet will persist between scenes so remember to switch the sprite back if it was supposed to be temporary.
When switching between scenes the player will always become visible at the scene start location regardless of previous visibility options. if you want the player to be hidden on a scene e.g when showing a title screen or cutscene add a Player Hide event to the scene's On Init script.
Actors are the characters and objects in your scene that you can interact with.
Adding an Actor
To add an actor to a scene click the + button in the Editor Tools and select Actor from the menu (alternatively press the A key), then click on the scene and position where you wish to place the actor.
The Editor Sidebar will switch to show the actor settings where you can give the actor a name for easier navigation later, reposition the actor (which you can also do with drag and drop), set the sprite sheet, initial direction, the movement type and create a script that will play when the player interacts with the actor.
There are a few different movement types available to choose, the one you should use will depend on how you want the actor to behave as the player is walking around the scene and interacting with it.
Static - The actor will display a single frame from the selected spritesheet.
If the sprite sheet contains more than one frame you will be given the option to choose which frame to display, this can be modified later using an Actor: Set Animation Frame event. Sprite sheets with multiple frames also enable the ability to optionally animate the actor by cycling through each of the frames at a specified speed, the speed can also be modified with an Actor: Set Animation Speed event.
The actor will only ever face in the initial direction (unless the direction is modified later using a script). If the player interacts with this actor it will not change direction. Useful for things like signposts or other stationary objects.
Face Interaction - The actor will start facing in the initial direction but when the player interacts with the actor it will turn to face the player before it's script plays. Useful for simple characters to make them more responsive to the player's actions.
Random Rotation - The actor will start in the initial direction but will randomly change direction at set intervals. Useful to show characters who are looking around their surroundings.
Random Movement - The actor will randomly change direction and move around the scene at set intervals. Useful for characters who are searching an area. Actors can block the player's movement so be careful not to use this movement type around tight spaces where the player might get stuck waiting for the actor to move out of the way.
Note If the actor uses a static sprite sheet (i.e. containing only a single frame of animation) then the only movement type available will be static and the inputs for choosing the movement type and initial direction won't appear.
Due to hardware limitations only 25 unique frames of animation can be allocated to actors in each scene. Where possible use static or non animated sprite sheets to decrease the number of frames used. Another way to reduce the frame count is to reuse the same sprite for multiple actors in the scene, reusing the same sprite sheet will not count towards the scene frame total.
Actors can have two scripts attached to them, On Interact and On Init, you can toggle between which script is being edited by using the tabs in the Editor Sidebar while the actor is selected.
The On Interact script will be run any time a player stands next to the actor and presses the A button.
The On Init script can be used to have events run as soon as the scene is loaded, they will execute before any events in the scene's On Init script.
When the actor is selected click the Add Event button in the Editor Sidebar to open the event menu and start building a script.
For more information see the documentation for Scripting.
Triggers are areas in a scene that, when the player walks over them, will cause a script to play. They are useful for creating doorways between scenes and to start cutscenes when the player moves to a specific position.
Adding a Trigger
To add a trigger to a scene click the + button button in the Editor Tools and select Trigger from the menu (alternatively press the T key), then click and drag across the scene where you wish to place the trigger setting the desired width and height.
The Editor Sidebar will switch to show the trigger settings where you can give the trigger a name for easier navigation later, reposition and scale the trigger and create the script that will play when the player walks on the trigger.
When the trigger is selected click the Add Event button in the Editor Sidebar to open the event menu and start building the script. For more information see the documentation for Scripting.
Scripting events allow you to dynamically control parts of your game based on interactions from the player. Use them to connect scenes together, to give dialogue to your characters or to create cutscenes.
When either a scene, an actor or a trigger is selected in the World Editor, the Editor Sidebar will contain an Add Event button at the bottom right corner, click this to add new events. If any events have already been defined they will be listed here with the topmost event being the first that will be run.
When adding events to actors they will run when the player stands next to that actor and presses the interact button. Events on triggers run when the player stands on top of the trigger which is useful for creating doorways between scenes. Events on scenes run as soon as that scene is loaded which is useful for configuring the scene based on values of variables or to kick off a cutscene.
After clicking the Add Event button a menu will appear to choose the event to add. If you start typing you can filter this list or you can scroll through it to find what you're looking for. Click an event or press the Enter key to add the highlighted event to your script.
Copy / Paste
Clicking the down arrow next to an event name in a script shows a dropdown menu where you can copy an event to your clipboard. Clicking this on another event allows you to paste the clipboard event either before or after the selected one or to just paste the values from the first event into the second.
New in 1.2.0
You can also hold the Alt key to turn all Add Event buttons into Paste Event buttons allowing you to easily paste events into control flow branches.
Text: Display Dialogue
Show a dialogue box with up to three lines of text, 18 characters per line (and a total of 52 characters), at the bottom of the game screen. This will likely be the most used script command for interacting with actors in your game.
When text is shown the dialogue box will slide up from the bottom of the screen and will slide down after it has been shown.
- Using the + button you can create a dialogue sequence which will only close after the last message has been displayed.
New in 1.2.0
- You can display the value of any variables in a text box by using the variable's identifier shown in the variable selector (e.g.
$L0$for local variable 0 and
$182$for global variable 182).
- You can optionally display an avatar image on the left hand side of the dialogue box by clicking Add Avatar and selecting an image to use. You are able to pick any sprite within your game that contains only a single frame (
16px). Setting an avatar will reduce the amount of characters per line available to 16 on all lines.
- Using the + button you can create a dialogue sequence which will only close after the last message has been displayed.
Text: Display Multiple Choice
Present two options to player allowing them to make a choice, will set the specified variable to true if the first option is chosen and to false if the second option is chosen.
Text: Display Menu New in 1.2.0
Display a menu of multiple options and set the specified variable to the value of the chosen option. Each menu item has a maximum length of
Multiple layouts are provided,
Menu(shown below) displays as a single column on the right hand side of the game screen and
Dialoguedisplays a full width dialogue box with two columns. You can optionally set the
Bbutton to close the menu setting the variable to
0and can also make the last menu item return
- Text: Set Animation Speed
Set the speed that dialogue boxes appear and disappear and how fast text appears within the box.
Scene: Change Scene
Transition to a new scene with player at a specified position and direction. A connection line will be drawn between the source of the event and the destination scene with a icon appearing at the destination position. It's possible to drag this icon around and between scenes to modify the event.
Scene: Store Current On Stack
Store the current scene and player state on to the scene stack, this allows you to return to this exact location later using the Scene Restore events. A common use of this event would be to include in a script just before a Change Scene event to open a menu scene, in the menu scene you could wait for the player to press a close button and then use the Restore Previous From Stack event to return to where the player opened the menu.
Scene: Restore Previous From Stack
Transition to the last stored scene from the scene stack using the specified fade speed. The previous scene will then be removed from the stack so the next time this event is used it will transition to the scene before that.
Scene: Restore First From Stack
Transition the very first scene stored on the stack, for instance if you had multiple levels of menu scenes you could use this to imediately return to the game scene. This event will cause the scene stack to become empty.
Scene: Empty Scene Stack
Clears the scene stack so that no previous scenes can be restored.
Your game has 512 variables that can be shared across all the scripts in your game. New in 1.2.0 Additionally every Actor, Trigger and Scene has 4 local variables that can only be accessed by that specific entity. Local variables are useful for keeping track of state specific to an entity such as how many times you have spoken to a character or if a treasure chest is open or closed.
Variable: Set To ‘True’
Set the value of the specified variable to true.
Variable: Set To ‘False’
Set the value of the specified variable to false.
Variable: Set To Value
Set the specified variable to a defined value.
Variable: Increment By 1
Increase the value of the specified value by one, up to a maximum of 255. If the value was previously false it will now be 1 (and also true), if it was previously true it will now be 2.
Variable: Decrement By 1
Decrease the value of the specified value by one, down to a minimum of 0. If the value was previously true it will now be 0 (and also false).
Variable: Math Functions
Allows you to perform various maths functions on a variable to add/subtract/multiply/divide/modulus a value/variable/random number.
Note: Variables have max values of 255 and will wrap if increased above 255 or below 0.
Variable: Set Flags New in 1.2.0
Set the value of a variable by enabling individual bits of the 8-bit number. Allows 8 true/false values to be stored within a single variable. Setting the flags will replace the previous value of the variable.
Variable: Add Flags New in 1.2.0
Set selected flags to true on a variable. All unselected flags will keep their previous value.
Variable: Clear Flags New in 1.2.0
Set selected flags to false on a variable. All unselected flags will keep their previous value.
Variable: Reset All Variables To ‘False’
Reset all variables used by your project back to false.
Control Flow Events
If Variable Is ‘True’
Conditionally execute part of the script if the specified variable is set to true.
If Variable Is ‘False’
Conditionally execute part of the script if the specified variable is false.
If Variable Compare With Value
Conditionally execute part of the script if the specified variable matches a rule, such as “Equal To”, “Greater Than” or “Less Than” against a value.
If Variable Compare With Variable
Conditionally execute part of the script if the specified variable matches a rule, such as “Equal To”, “Greater Than” or “Less Than” against a second variable.
If Variable Has Flag New in 1.2.0
Conditionally execute part of the script if the specified variable has the chosen flag set as true.
If Joypad Input Pressed
Conditionally execute part of the script if the specified joypad input is currently pressed. Will not wait for user input so use directly after a Joypad Input: Pause Script Until Pressed event if waiting is required. Event will only execute once, if you wish to run a script every time a button is pressed use Joypad Input: Attach Script To Button instead.
If Actor At Position
Conditionally execute part of the script if the specified actor is at a certain position in the scene.
If Actor Facing Direction
Conditionally execute part of the script if the specified actor is facing a certain direction.
If Game Data Saved
Conditionally execute part of the script if there is a saved game available.
Switch New in 1.2.0
Conditionally execute from multiple options depending on the value of the specified variable. First choose how many options you want to compare the variable against, then set the values to compare and what scripts to execute when the value is matched.
Execute part of the script in a loop forever. Remember to break out of the loop otherwise the player will become stuck at this point. You can use a Stop Script or Change Scene event to stop the loop.
Label: Define / Label: Goto New in 1.2.0
Define markers in your script using Label: Define giving the label a name and jump to markers using Label: Goto.
Note: The name must be identical for the define/goto event pair to work. Use with care!
Provides no in game functionality but allows you to group a sequence of events together and give them a label (using the Rename Event option on the event menu) and collapse the events into a single block.
Stops the current script from running.
Disable Else New in 1.2.0
If you don't require an Else branch in any of your control flow events you can now disable it by selecting Disable Else from the event dropdown menu. The same menu can be used to restore an Else branch if needed at a later time.
Camera: Move To
Move the camera to a specifed position in the scene.
Camera: Lock To Player
Move the camera back to focusing on the player, locking into position when the player moves.
Shake camera effect for up to 10 seconds.
Screen: Fade In
Fade the scene to a white screen.
Screen: Fade Out
Fade the scene in from a white screen.
Actor: Set Direction
Set the facing direction of the specified actor.
Actor: Set Direction Using Variable New in 1.2.0
Set the facing direction of the specified actor from the value of a variable.
Actor: Set Position
Set the position in the scene of the specified actor.
Actor: Set Position Using Variables
Set the position in the scene of the specified actor from the values of two variables.
Actor: Set Relative Position
Set the position in the scene of the specified actor relative to their current position.
Actor: Move To
Make the actor walk to a specified position in the scene. Actor will ignore all collisions along path so combine multiple of these events if you need to specify an exact path avoiding obstacles in the scene.
Actor: Move Relative
Make the actor walk to a position relative to their current position.
Actor: Move To Using Variables
Make the actor walk to a position from the values of two variables.
Actor: Store Position In Variables
Store the current position of an actor into two variables.
Actor: Store Direction In Variable New in 1.2.0
Store the current direction of an actor into a variable.
Actor: Push Away From Player
Push an actor in the direction the player is currently facing. By default pushes by one tile, but can optionally slide until a collision occurs.
Actor: Emote Bubble
Display an emote bubble above the specified actor from one of Shock, Question, Love, Pause, Anger, Sweat, Music and Sleep. You can change the graphics used for these bubbles by editing the UI Elements of your game.
Actor: Set Animation Frame
Set the current animation frame of the specified actor.
Actor: Set Animation Frame Using Variable New in 1.2.0
Set the current animation frame of the specified actor to the value of a variable.
Actor: Set Animation Speed
Set the animation speed of the specified actor.
Actor: Set Movement Speed
Set the movement speed of the specified actor.
Actor: Set Player Sprite Sheet
Change the player sprite sheet from the default defined in the Project Editor. Changes to the player sprite sheet will persist between scene transitions so make sure to change it back if the change was supposed to be temporary.
Actor: Collisions Disable New in 1.2.0
Prevent collisions from affecting the selected actor. If a scene actor is selected then the player will be able to walk through them, if the player is selected then you will be able to walk through all actors and collisions in the scene.
Note: While collisions are disabled it is still posible to interact with the actor.
Actor: Collisions Enable New in 1.2.0
Reenable collisions on the selected actor.
Actor: Invoke Script
Call the script on another actor in the scene as if the player had interacted with that actor.
Hide an actor so it is no longer visible. Hidden actors will no longer cause collisions and will not be able to be interacted with. You can hide the player on a Scene Start Script to make menu and title screens.
Unhide a previously hidden actor.
Sprites: Hide All
Hide all sprites in scene. Can be useful to create cutscenes where the player should not be visible by adding to a scene's starting script.
Sprites: Show All
Show all sprites that were previously hidden.
Show either a black or white window over the top of the current game screen. Can be used to obscure and then reveal parts of the scene background for example on the sample project logo screen.
Hides the screen overlay.
Overlay: Move To
Moves the overlay to a new position on the screen.
Joypad Input: Pause Script Until Pressed
Pauses the script until one of the specified joypad inputs are pressed.
Joypad Input: Attach Script To Button
Execute the specified script any time a joypad input button is pressed. If you attach scripts to a direction button or the A button the scripts will override the default game actions.
Joypad Input: Remove Attached Script
Remove an attached script from a joypad input button restoring the default functionality of the button.
Music: Play Track
Plays a music .mod file, optionally looping the file when finished. If you play a new song while another song is playing, the old song will stop automatically.
Stops any currently playing music. Put this before a Music: Play Track event to restart the same song from the beginning.
- Sound: Play Effect New in 1.2.0
Play a sound effect, choose from playing a beep with a given pitch, a tone with a given frequency or cymbal crash. Using Custom Events you can combine multiple effects into a single reusable event to make jingles.
Pause script for up to 10 seconds.
Timer: Set Timer Script New in 1.2.0
Execute the specified script repeatedly after a time interval. The script will keep running in the background until a Disable Timer Script event is called or the scene is changed using a Change Scene event.
Timer: Restart Timer New in 1.2.0
Reset the countdown timer back to zero. The script will call again after the time specified originally.
Timer: Disable Timer Script New in 1.2.0
Remove the timer script so it will no longer be called.
Game Data Events
Game Data: Save
Save the current game data.
Game Data: Load
Load the previously saved game data.
Game Data: Clear
Remove any previously saved game data.
- Comment New in 1.2.0
Provides no functionality in game but allows you to leave notes within your scripts. The text you type automatically gets set in the event title so you can collapse the comment and still read its content.
You can also use the event dropdown menu to disable and reenable any event.
Disabled events will be skipped when run in game.
New in 1.2.0
Custom Events allow you to create reusable procedures in your game that can be used across any of your scripts.
Clicking in the background between scenes switches the sidebar back to the Project Editor which will list any Custom Events in your project along with a button to Create Custom Event.
Once you've given your Custom Event a name you can start building a script in the same way you would for Actors, Triggers and Scenes.
Whenever you add an event that reads a Variable it will get added to the list of input parameters for the Custom Event, where you are able to give that input a memorable name. Events that affect Actors will, by default, apply to the player but if you use the actor selector you will be able to set the event to read the Actor value from an input parameter also.
For example the following custom event makes
Actor A rotate in a circle.
This custom event can then be used within Actor, Trigger and Scene scripts where it will appear as follows.
If you ever want to edit the Custom Event you can return to it using the list on the Project Editor or by selecting Edit Custom Event from the event dropdown menu.
When your project was created an
assets folder was also made within the project containing a number of subfolders for each asset type in your game.
GBStudio doesn't currently contain any ability to edit the graphics or music in your game directly, you instead can use your favourite existing applications and save files into these folders where they will instantly appear ready to use in your project. If you edit a sprite or background PNG file and save using an external image editor the change will be seen in your Project Window as soon as you switch back it.
While you can create graphics in any application that can output PNG files it is recommended to use Aseprite or Photoshop to create your sprites and UI elements then to use Tiled Map Editor to create your backgrounds. Each image asset type has a different set of requirements detailed over the new few sections of this documentation.
If you're looking for a collection of free assets, ready to be used in GB Studio there is a community run repository on Github available at GB Studio Community Assets.
Sprites are the graphics used by playable or interactive characters in your scenes. Add sprites to your game by including PNG files in your project's
Sprite PNGs must only contain the following four colors:
#65ff00 is used to represent a transparent background in game and will be invisible in-game and in the World Editor.
Colors that are not one of the above hex codes will be matched to the nearest color. Unlike backgrounds, the color
#306850 can not be used in sprites.
A sprite consists of one or more
16px frames laid out horizontally in file. A sprite with a single frame will be
16px while a sprite with three frames will be
For sprites that only need a single frame (e.g. static items such as signposts) create your PNG as a
16px image containing just the one frame required.
If you want to have sprites that play short animations you can make a PNG with between 2 frames at
16px and 25 frames at
16px. Using these sprites on an actor will enable you to select which frame you want to display by default and will allow an animation to be played at a specified speed.
To make sprites that can face in four directions turning towards the player, create a
16px PNG containing the three frames forward facing, upwards facing and right facing. The left facing sprite is automatically generated by flipping the right facing sprite horizontally so does not need to be created.
To make sprites that have animated movement, or that can be used as a player character, create a
16px PNG containing six frames, two forward facing, two upwards facing and two right facing animation frames.
As there are limits to how many sprites frames can be loaded into a single scene don't use animated sprites unless you know your NPCs will need animated movement.
Each of your scenes requires a background image that defines how that scene should look. You can add backgrounds to your game by including PNG files in your project's
Background PNGs must only contain the following four colors:
Colors that are not one of the above hex codes will be matched to the nearest color. Unlike sprites, the color
#65ff00 can not be used in backgrounds.
Backgrounds are divided into
8px tilesets so the total image size must be a multiple of
8px in both width and height. A background has a minimum size of
144px (the screen size) and currently a background can be no larger than
An image can contain no more than 192 unique
8px tiles at once due to memory limits. This means that even using the smallest background size possible you must repeat about half of your tiles. Where possible repeat tiles between images as they will be grouped together saving on total game size. It is recommended to use a tile map editor such as Tiled to ensure your backgrounds conform to the pixel grid.
Your project contains a number of files in
assets/ui with fixed file names that define parts of your game's user interface. Editing these files allows you to change the default font, set the window frame and modify the selection cursor.
If you remove any of the files in the ui folder they will be replaced with the default assets the next time you build your game allowing you to revert any unwanted changes.
Edit this file to change the game's font when talking to actors in your game.
The game engine uses 9-slice scaling of this image to create the frame around text boxes. Editing this image will allow you to change the frame design or set it to a solid color.
This image is used as a selection cursor when showing multiple choice options in your game.
This image used to define the look of the emote bubbles that can be shown above actors using scripting. Each bubble is
16px in size and the each bubble represents Shock, Question, Love, Pause, Anger, Sweat, Music and Sleep in that order left to right.
With the exception of
emotes.png which follows the standard sprite requirements, UI PNGs must only contain the following four colors:
Music can be played in your game using the Music: Play event in your Actor, Trigger, or Scene scripts.
Add music to your game by including .mod files in your project's
assets/music folder. GB Studio uses GBT Player which is a driver that takes .mod files and converts them to instructions for the Gameboy. GBT Player interprets .mod files differently than the Amiga computers that the .mod format was originally designed for, so every .mod file that GBT Player reads should be composed/arranged to be used with GBT Player.
As an alternative to composing, there is a way to import .midi files to OpenMPT for playback in GBT Player. More information can be found under Frequently Asked Questions. You can also browse the GB Studio Community Assets to find free, GBT-compatible music under the MIT licence.
To compose GBT-compatible .mod files, you can use software such as OpenMPT (for Windows or Linux using Wine), MilkyTracker (for Windows, Mac and Linux), ProTracker, and BassoonTracker (browser-based) to name a few. Any software that loads and exports .mod files can write files that are compatible with GBT Player.
It is recomended you read through your tracker's documentation to learn about your tracker:
Lastly, the GB Studio Discord also has a dedicated #music-help channel and a #tutorials channel in case you get stuck.
- Create a blank GB Studio project, find the file
assets/music/template.modand open it with your tracker of choice.
- You must edit this file to get an accurate representation of the instruments you can use.
- MilkyTracker users should save this file as an
.XMfile. Saving a .mod file in MilkyTracker will corrupt it. Export your song as a .mod file every time you want to test your song in-game.
- Use the instrument list shown later in this document to pick the sounds you want. Changing the samples in your tracker will not affect how they sound in-game.
When done, add your .mod files to the
assets/music folder of your project. Test your song in-game often to keep track of any audible in-game differences.
Here is a quick rundown of how a tracker works:
C-5 01 v64 ... --- -- --- --- | | | | | | | +-- Effect column (Volume changes, arpeggios, panning, etc.) | | +------ Volume value, this is irrelevant in .MOD. (Most examples here omit this | | and instead display three dots in its place) | +--------- Instrument +------------- Note and octave (A C note in the 5th octave. The dash can be a #, which signifies a sharp note e.g. C#, D#)
This is what comprises of a channel's row. Rows can be empty, or can only be partially filled (with just an effect, for example). There's 4 of those columns in total.
Any part in this documentation where you see data that starts with
ModPlug Tracker MOD, you can copy that entire block into OpenMPT as-is. Any data copied from OpenMPT looks like that when you paste it into any text application.
GBT Player's Channel Limitations
.MOD files need to use 4 channels. Loading a copy of template.mod before composing will ensure this is set-up correctly.
|Channel #||Sound type||Note Range1||Instruments||Effects|
|Channel 1 & 2||Pulse||C3 to B8||1-4||0, C, E8, EC, B, D, F|
|Channel 3||Waveform||C3 to B8||8-15||0, C, E8, EC 2|
|Channel 4||Noise||Only C5||16-31||C, E8, EC, B, D, F|
1 This range is for One-Indexed Trackers (C1 is the lowest-possible note). This is comparable to OpenMPT in default settings. Trackers that are Zero-Indexed by default (C0 is the lowest-possible note) should interpret these Note Ranges a full octave down. This is comparable to MilkyTracker in default settings.
Using default settings on OpenMPT and MilkyTracker, C3 to B8 in OpenMPT sounds the same as C2 to B7 in MilkyTracker.
2 Effects B, D, and F can be also used on Channel 3 if the same row isn't being used to set a note/instrument.
Currently, volume can only be adjusted by using the
Cxx effect for each channel.
The Gameboy has 16 unique volume settings for Channels 1, 2 and 4. GBT Player will floor (round-down) the values in a
Cxx volume effect to multiples of 4.
Unique Volume Settings for Channels 1, 2 and 4:
00, 04, 08, 0C, 10, 14, 18, 1C, 20, 24, 28, 2C, 30, 34, 38, 3C
Any number that's not a multiple of 4 will be rounded-down to one of the above numbers.
C03 will sound the same as entering
C40 will sound the same as entering
Channel 3 is the exception to this with only 4 unique volume settings.
Unique Volume Settings for Channel 3:
00, 10, 20, 40
GBT Player will round
Cxx effects on Channel 3 to the nearest number listed above.
C30 will round the volume up to
In most trackers, if a note is played without a volume command, the note's volume is reset to the maximum. When a .mod file is converted by GBT Player, notes without a volume effect will play at the same volume as the previous
Cxx effect that the channel read. For example, take this scenario:
ModPlug Tracker MOD |C-502...C40| |...........| |...........| |...........| |........C..| |...........| |E-502......|
In the tracker, the E-5 note will resume at full volume after the C00 effect.
In-game, you will not hear the E-5 note. This is because the C00 persists until another
Cxx effect is set. To make the tracker playback sound identical to the in-game playback, the following must be done:
ModPlug Tracker MOD |C-502...C40| |...........| |...........| |...........| |........C..| |...........| |E-502...C40|
Additionally, Channel 3 requires that the instrument and note is set during a volume change for the volume change to have any effect. (Except for
C00.) For example:
ModPlug Tracker MOD |C-511...C40| |...........| |...........| |...........| |........C20| |...........| |G-511...C40|
You will not hear any volume change from the C20 in-game. Add a note and instrument on
C20 to register the volume change.
ModPlug Tracker MOD |C-511...C40| |...........| |...........| |...........| |C-511...C20| |...........| |G-511...C40|
All numbers listed here are in base-10 unless otherwise noted.
The pulse channels 1 and 2 have four instrument options:
- 25% pulse
- 50% pulse (square wave)
- 75% pulse (inverted 25% pulse)
- 12.5% pulse
Instruments 5 through 7 are intentionally left blank.
Channel 3, the wave channel, has 8 instrument options:
- Buzzy (Source code calls this “random :P”)
- Ringy (useful for SFX)
- (A) Sync Saw
- (B) Ring Saw
- (C) Octave Pulse + Triangle
- (D) Sawtooth
- (E) Square
- (F) Sine
As of GB Studio 1.2.1, GBT Player uses 16 instruments to access pre-determined noise settings - instruments 16 to 32.
Instruments 16 to 23 use Periodic (looped) Noise at various pitches, while instruments 24 to 32 use Pseudorandom noise at various pitches.
The nicknames and descriptions next to these instruments are not official for GBT Player, they are intended to help identify these noise presets at a glance.
- (10hx) “stutter” - A square plus a pulse at random pulse widths
- (11hx) “rumble” - The same waveform but faster
- (12hx) “engine” - The same waveform but even faster
- (13hx) “low tone” - Sounds like D5
- (14hx) “undertone” - Sounds like E5 + 50cents
- (15hx) “middletone” - Sounds like B5 + 50cents
- (16hx) “overtone” - Sounds like D6 + 50cents
- (17hx) “high tone” - Sounds like D7
- (18hx) “earthquake” - A square with a thin pulse at random pulse widths
- (19hx) “spaceship” - The same as 24 but faster
- (1Ahx) “ocean” - etc.
- (1Bhx) “scratch” - etc.
- (1Chx) “glitch” - A fairly clean white-noise sample, unrelated to other instruments
- (1Dhx) “volcano” - A pulse with rapidly changing pulse width
- (1Ehx) “scream” - The same as 29 but faster
- (1Fhx) “static” - etc.
As of GB Studio 1.2.1 there are no GBT Player-readable instruments beyond 31. (1Fhx)
There are two types of effects: Note-effects and Command-effects.
The only restrictions on effects is the Command-effects with Channel 3. It can use them when it's not trying to play a note/set the instrument on the same row.
Note-effects (uses bit 3) - All channels can use these effects freely
|Effect||Name||Notes on effect usage|
|0xy||Arpeggio||Rapidly cycles between 3 notes.
|Cxx||Volume||Sets the volume to
|E8x||Pan||Sets the panning to
|ECx||Note cut||Cuts the note after
Command-effects (uses bit 4) - Channel 3 can use these effects if it's not trying to play a note/instrument on the same row.
|Effect||Name||Notes on effect usage|
|Bxx||Jump||Jump to a specific position in the song,
|Dxx||Pattern break||Jumps to the next pattern early, where
|Fxx||Set speed||Sets the song speed to
For Channel 3 only, the instrument data is too large to allow the 4th bit of a Command effect to occur while it's trying to play a note/set the instrument. Command-effects will ignore new notes on Channel 3 to compensate.
|Fxx Value (in tracker)||BPM (in tracker)||BPM (in game)|
|F011||750 BPM||900 BPM|
|F021||375 BPM||450 BPM|
|F031||250 BPM||300 BPM|
|F041||187.5 BPM||225 BPM|
|F05||150 BPM||150 BPM|
|F06||125 BPM||128.57 BPM|
|F07||107.14 BPM||112.50 BPM|
|F08||93.75 BPM||100 BPM|
|F09||83.33 BPM||90 BPM|
|F0A||75 BPM||81.82 BPM|
This is not a full table, it's just the top few speeds. It's here to highlight some of the speed discrepancies, albeit small to not be very noticeable, with the exception of the values marked with 1.
You might notice that the value of the F effect, when converted to decimal, is just the speed divisor. For instance, F03 divides the BPM by 3 (
750 / 3 = 250, or
900 / 3 = 300).
Because of how GB Studio is set up, a 60hz F05 effect, which would result in 180 BPM in-game, is impossible here.
While not in GB Studio, GBT has a flag called
-speed that will handle BPM differently, which would require F96 effects for every speed, as it won't handle any internal conversions to get the speed closer. This is the reason why F01 to F04 require F96 in both modes, there's no equivalent for it in tracker speed.
1. Values marked with 1 require an additional F96 effect for the song to sound closer in speed when converted, or setting the song BPM to 150. This F96 effect can be removed once you're done with your song, there won't be any difference as GBT ignores this – It's only here to set the BPM to something closer to the in-game version.
Tricks and Tips
1. High Speed
By using F01 to F04, you can achieve much higher granularity when it comes to changing volumes and creating sounds of sorts. This means that with a high enough speed, you can create more varied bodies for sounds, with sort-of envelopes, or elaborate effects (like 1 channel echos, which I'll cover here in a moment).
This trick means you're going from drums that sound flimsy and primitive to something more impressive.
Here's an example of a Snare Drum, at speed F02, that might sound good for you.
ModPlug Tracker MOD |C-526...C40 |C-527...C28 |........C20 |........C18 |........C10 |........C08 |........C04 |........C.. (this is on the noise channel)
If this is longer than what you need, simply crop it starting from the bottom.
You can also use this for tones and stuff, like short staccato notes or flutes that fade in.
If you do this, keep in mind the GB Sound hardware has an annoying bug that resets the phase of each waveform on a volume set, meaning you can get scratchy noise in a few emulators and also the real GB.
2. One channel echoes
This works on most speeds. This is useful for when you need a melody on top of some sort of echoing ostinato, or phrase, or whatever.
To illustrate it, I'm going to try illustrating it like this, instead of a tracker layout:
A _ B _ C _ E _ G _ E _ C _ B _ Without 1ch Echo +-----+ +-----+ +-----+ A _ B a C b E c G e E g C e B c +-----+ +-----+ +-----+ +-----+ With 1ch Echo (lowercase notes are the echoes)
Notice how each lowercase letter takes the form of it's 3 step behind louder cousin? That's how the trick works. By having shorter notes that, on each step, has another quieter note that's way behind, you get a cool echoing effect.
I can't explain it very well via text, so I recommend you check out this video by explod2a03 covering how this trick works with a better example and actual audio: https://www.youtube.com/watch?v=6GI9gngTn_Y
The best way to do this in a tracker is to use a channel you're not using temporarily, copy your note sequence to it, delay it by 3 (or however many you need) rows, then right clicking on the selection and clicking “Amplify…", and setting the amplitude to something lower than 50%.
After that, you should have both channels “alternate”. Select the entirety of the channel with the echoes (from top to bottom), go to the channel you want to merge the echoes with, right click, go to “Paste special”, then click “Mix paste” (This should have a shortcut, might want to learn it as it can be fairly useful).
3. Quick volume envelopes
Are you in a hurry? No problem, this simple trick will create linear envelopes:
- Select two volume / C values of two separate notes (within the same channel), and everything in between
- Right click and hover over “Interpolate”
- Click on “Effect column”
- You're done!
You might wonder how's it going to sound in-game; well, it'll sound as close as possible. The volumes it can't play it'll just clamp it to the nearest ones it can play.
Frequently Asked Questions
Q: Can I use mp3/wav files?
A: No, but you can use .midi files. If you're looking for an easy way to add music to your game, you can ask the #collaborations channel of the GB Studio Discord or browse the GB Studio Community Assets.
This has limited success, and there are easier options to get music in your game, such as the
Q: How do I convert a .midi file to .mod?
A: OpenMPT can open MIDI files and save the result to .mod Some resources on how to do this include a video tutorial as well as Kazy's write-up article pinned in the #music-help section of the GB Studio discord.
Q: Can I use this .mod file I found online?
A: It won't sound as intended, but it can be made to sound good-enough with some adjustments. Any
=== notes need to be replaced with the
EC1 effect. All instrument restrictions should apply, and no melodic instruments should be using Channel 4. You may also need to transpose the notes of a channel to account for differently-tuned samples, which you can learn more about in your tracker's documentation.
Q: How do I stop a note from playing?
EC1 will mute a channel's note,
C00 will mute the channel until it recieves another
Q: What do I do if my song sounds completely giltched-out?
A: It's probably corrupted. It can likely be saved by using OpenMPT and saving it as a different filetype. If you're using MilkyTracker, don't press “Save” on a .mod file, always work in a .xm file instead.
Q: Why is my song speed is faster in-game than it is in the tracker?
A: If you're using an
Fxx effect with a value lower than
F96 to the first row of your song. This will not impact your in-game playback speed.
Q: Can I play back voice clips/sound effects?
A: Not on GBT Player. Pokemon Yellow's method is unique, and LSDj does not leave much processing power for games to be played while it's running.
Q: Can I use a different tool to write my music?
A: If the tool can natively export to .mod, try it!
Q: Why is my song playing glitched sounds when it tries to loop?
D00 is a problematic effect, try using
Bxx instead. If you're already using
Bxx, make sure the
xx number does not go above the number of pattern-slots in your song. A song's first pattern is always in slot 00.
Q: Why do some notes in OpenMPT appear red and sound higher/lower than they're supposed to sound?
A: Go over to the “General” tab that's under the New File, Open and Save buttons. Click the big button next to the “Name” field that says “MOD (ProTracker), 4 channels”. Once there, disable both ProTracker 1/2 Mode (MOD) and Amiga Frequency Limits. This is a thing because the format here is meant to be used with the Amiga line of computers (that's where it was made), which has frequency limits.
Q: Why does my song start out with garbage noise?
A: If your song doesn't start using the first two channels, add a note to their first row with a
C00 effect on each.
Q: Can I play sound effects?
A: Yes, with limitations. View the next page of the documentation for more information. Playing sound effects will not interrupt the song being played by GBT Player.
- Make sure you save frequently and also back-up your files. This is important in anything that you do and it's worth mentioning here.
- If you're stuck, please ask for help in the Discord server, in
#music-help. There's usually a few handful of people who are willing to help out at most times.
- Frequently try out your music in your game. Things don't sound 1:1, and the built in preview just plays the .mod file rather than building the music and previewing that.
- Keep it simple! Don't jump into this, trying to emulate what several artists have done with LSDj or whatever other tools, you'll just get stuck.
- Don't be afraid of failure. I get this is kind of an unfitting tip, but it's important. Your first song won't be good, and that's okay. You'll fail, sure, but you'll also gain knowledge on what you might've done wrong, or how you want to go on about with your next endeavor.
- OpenMPT has a manual to help you get started. Here's a link, give it a read if you're stuck (or just ask for help)
- Give the GBT Player documentation a read.
New in 1.2.0
Sound effects can be added to your game using the Sound: Play Effect event in your Actor, Trigger or Scene scripts.
You can choose from playing a beep with a given pitch, a tone with a given frequency or cymbal crash.
Using Custom Events you can combine multiple effects into a single reusable event to make jingles.
Building Your Game
Clicking the Play button in the top right of the Project Editor window will start a build of your game and once complete will open a new window where you can play your game. See Keyboard Shortcuts for details on how to play your game in the Play Window.
Clicking the Project Navigator and selecting Build & Run will take you to the Build Terminal where you can see a log of the project build. You also get to this screen by clicking the Play button while a build is taking place. This screen will show you if there's any errors in your build to help you correct them.
Build as ROM
Clicking the Export button and clicking Export ROM will build your game and create a ROM file in your project's build folder as
$PROJECT_ROOT/build/rom/game.gb. You can play this ROM file in any compatible emulator such as OpenEMU or KiGB.
Build and deploy for Web
Clicking the Export button and clicking Export Web will build your game and create a HTML5 web build in the folder
$PROJECT_ROOT/build/web. You can upload this folder to any web server and navigate to the
index.html file to play your game in a web browser. If you use a mobile or tablet web browser the game will also include touch controls.
If you zip the
build/web folder you can upload it to Itch.io as a HTML game. In this case the recommended viewport size to use is
On macOS if you're having trouble building or running your game you may also need to install Apple's Command Line Tools by opening
Applications/Terminal.app and entering the following command.
On Windows you may need to whitelist the application in your Anti Virus software to perform a build.
New in 1.2.0
Clicking the Project Navigator and selecting Settings will take you to a list of your project's settings.
GB Color Options
GB Studio has some limited support for GB Color when your game is run on compatible hardware or emulators. There are two options currently available:
Use Double Speed Mode - When enabled allows the game engine to make full use of the GB Color's increased CPU speed. Enabling this option helps prevent music skipping when transitioning between scenes.
Use Custom Color Palette - When enabled allows the four colors in your game's color palette to be replaced. Click on the color you wish to replace then choose the red, green and blue values to use or enter a hex color value and click Convert Hex to match the closest available color.
Using a custom color palette you can create a drastically different tone for your game! Try experimenting to see what you can come up with. If you don't like your color palette you can always click Restore Default to the get the original palette back again.
The Controls section allows you to override the default controls used when playing your game from a web build and the Play Window.
To edit the controls for a button click on the input box and while the input is highlighted type the key you wish to assign. To remove all the assigned keys click the input and then press the Backspace key on your keyboard.
To reset to the original controls you can use the Restore Default button.
The Cartridge Type section allows you to choose which Memory Bank Controller you want to use and if a battery will be included when exporting your game to a physical cartridge (requires additional hardware and software).
If you don't know what these settings mean it's best to keep this as the default of MBC5+RAM+BATTERY which you can do by using the Restore Default button.
Custom HTML Header
You can use the Custom HTML Header section to add content to the HTML