ZGB

ZGB is a Game Boy / Game Boy Color engine that lets you write your own games in C or asm.

It uses GBDK 2020 but expands it to give you some common functionallity for writing games such as: a main loop, sprites spawning, sprites life cycle, sprites animations, collison management, easily getting assets into the game, music, fx...

Getting started

• Installing ZGB
  • Download the latest release
  • Run install.bat (this will create a new environment var ZGB_PATH pointing to %ZGB%/common)

    NOTE: ensure ZGB path doesn't contain any spaces (more info here)

• Creating a new project
  • Download the ZGB-template and build it running build.bat
  • Follow the tutorial on the wiki to understand the basic concepts of the engine
• (Optional) Download Microsoft Visual Studio Community Edition The ZGB-template comes with a solution customized for visual studio

Documentation

Check the wiki and this README

Support

• twitter: Zal0
• discord: gbdk/zgb discord

Features

(Click on any feature to expand it)

Sprites

You can manually add Sprites calling **SpriteMangerAdd**(type, x, y). ZGB will call the **START** function of this Sprite first and then it will call **UPDATE** on each frame until the Sprite is removed. You can manually remove an Sprite with the function **SpriteManagerRemove** (faster) or **SpriteManagerRemoveSprite** and then the engine will call its **DESTROY** function. Sprites will also be removed when getting off screen limits. You can configure how far you allow them to go before the engine disposes them with the fields **lim_x** and **lim_y** Usually you will create an Sprite in the START function of your State and assing it to scroll_target, so that the camera follows it ```C void START() { scroll_target = SpriteManagerAdd(SpritePlayer, 50, 50); ... } ``` You can create your sprites with the Game Boy Tile Designer or you can use pngs. Create your sprites in the res/sprites folder so that the Makefile can identify them as sprites and pass the proper parameters to png2asset.

gbr sprites

Use Game Boy Tile Designer included in /env/tools/gbtd22/GBTD.exe to create gbr sprites. Don't worry too much about the TileSize choosen, remember that empty tiles will be discarded The first time you compile the gbr a .meta will be created with the default params passed to png2asset. You may want to take a look specially at the collision info to adjust the collider ``` -px 0 -py 0 -pw 32 -ph 32 ``` Check the png2asset params [here](https://gbdk-2020.github.io/gbdk-2020/docs/api/docs_toolchain_settings.html#png2mtspr-settings)

png sprites

GBTD has a few limitations: - The maximum sprites size is 32x32 - It only lets you choose a palette for the whole metasprite Luckily you can overcome these limitations by using your preferred pixel art software and then export your data as a spritesheet As with gbr sprites a .meta file can be created to pass arguments to png2asset. Contrary to gbr sprites this .meta file won't be created automatically so it is important that you create a it and at least indicate the sprite dimensions (or it will be exported as a single sprite) ``` -sw 32 -sh 16 ``` Check the png2asset params [here](https://gbdk-2020.github.io/gbdk-2020/docs/api/docs_toolchain_settings.html#png2mtspr-settings)

Creating a new Sprite

The template already comes with a placeholder Sprite but you surely will need to add more. Yo do this by following the next 3 steps: 1. Create the sprite image data. 2. Create a new file < YourNewSprite >.c containing this: ```C #include "Banks/SetAutoBank.h" void START() { } void UPDATE() { } void DESTROY() { } ``` 3. Register this new Sprite in ZGBMain.h ```C #define SPRITES \ ... _SPRITE_DMG(, )\ SPRITE_DEF_END ```

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