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
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 + 1-7
Run Game - Ctrl/Cmd + B
Export ROM file - Ctrl/Cmd + Shift + B
Setting the Player Starting Position
You can reset the player starting position by clicking into any scene and pressing the P key.
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.
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 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. 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 start 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.
New in 1.1.0
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.
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.
Text: Display Dialogue
Show a dialogue box with up to three lines of text, 18 characters per line (16 on the third line), 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.
New in 1.1.0
- Using the + button you can create a dialogue sequence which will only close after the last message has been displayed.
- You can display any of the first 100 variables in a text box by using the variable’s identifier $00$ to $99$.
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: Set Animation Speed New in 1.1.0
Set the speed that dialogue boxes appear and disappear and how fast text appears within the box.
Scene: Switch 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 New in 1.1.0
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 Switch 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 New in 1.1.0
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 New in 1.1.0
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 New in 1.1.0
Clears the scene stack so that no previous scenes can be restored.
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 New in 1.1.0
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: 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 New in 1.1.0
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 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 New in 1.1.0
Conditionally execute part of the script if the specified actor is facing a certain direction.
If Game Data Saved New in 1.1.0
Conditionally execute part of the script if there is a saved game available.
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 Switch Scene event to stop the loop.
Event Group New in 1.1.0
Provides no 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.
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 Position
Set the position in the scene of the specified actor.
Actor: Set Position Using Variables New in 1.1.0
Set the position in the scene of the specified actor from the values of two variables.
Actor: Set Relative Position New in 1.1.0
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 New in 1.1.0
Make the actor walk to a position relative to their current position.
Actor: Move To Using Variables New in 1.1.0
Make the actor walk to a position from the values of two variables.
Actor: Store Position In Variables New in 1.1.0
Store the current position of an actor into two variables.
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 New in 1.1.0
Set the current animation frame of the specified actor.
Actor: Set Animation Speed New in 1.1.0
Set the animation speed of the specified actor.
Actor: Set Movement Speed New in 1.1.0
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: Invoke Script New in 1.1.0
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 New in 1.1.0
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 New in 1.1.0
Remove an attached script from a joypad input button restoring the default functionality of the button.
Music: Play Track
Plays a music file, optionally looping the file when finished.
Stops any currently playing music.
Pause script for up to 10 seconds.
Game Data Events
Game Data: Save New in 1.1.0
Save the current game data.
Game Data: Load New in 1.1.0
Load the previously saved game data.
Game Data: Clear New in 1.1.0
Remove any previously saved game data.
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.
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:
GB Studio is internally using GBT Player. Additional documentation and sample MOD files can be found in its own repository.
When done, add your MOD files to the
assets/music folder of your project.
Due to the limits of the Gameboy’s hardware, there can only be 4 channels in a MOD file.
The first two channels generate pulse waves. The pulse width can be changed by adjusting the channel’s instrument parameter from 1 to 4.
The third channel generates a variety of pre-set waveforms. You can change the waveform by setting its instrument parameter from 8 to 15.
The fourth channel generates a variety of noise waveforms. You can change the waveform by setting its instrument parameter from 16 to 31.
|Channel #||Waveform||Note Range*||Instrument Range||Effects Allowed|
|Channel 1||Pulse||C3 to B8||1-4||All effects|
|Channel 2||Pulse||C3 to B8||1-4||All effects|
|Channel 3||Wave||C3 to B8||8-15||Only effects 0, E8 and EC|
|Channel 4||Noise||Only C5||16-31||All except 0|
*This note range is for trackers that display notes between C1 and C8 such as OpenMPT. Trackers that display notes between C0 and C7 such as MilkyTracker should use transpose these guidelines an octave down.
GBT Player reads effect
f as song speed.
f defines how many in-game frames should pass before the next tick of the MOD file is played.
f01 is the fastest and plays 1 tick per frame.
f1f is the slowest speed and plays 1 tick every 32 frames. This effect can be set on any channel except channel 3.
For newer composers, it’s a good idea to test your music after creating a few patterns to identify any audible differences between GBT Player and your tracker.
To prevent notes that overlap when looping your song in-game, enter
00as the note’s volume on the tick it should stop playing.
MilkyTracker will not save MOD data correctly when making edits to existing MOD files. You can prevent this by savings songs as .xm and exporting to .mod when you are finished.
Check out the README and documentation of GBT Player for more on how the software works.
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.