PicoSystem 32blit Match 3 Demo

A Match 3 game to demo how to build games for the Pimoroni PicoSystem.

The how's and why's of the code are being documented in the picosystem-demo Wiki, which should help provide some info on the 32blit SDK and how it is used to build the game.

Tools Used

Artwork

Krita was used to create pixel art for all assets.

Maps

Maps are generated using Tiled.

Building the Demo

This demo was created with macOS 11.6 (Big Sur), and most of these instructions will work with Linux or WSL (Windows Subsystem for Linux) equivalents.

Compilers & Libraries with macOS

You'll need a compiler and a few other dependencies to get started building C++ for PicoSystem. With macOS that will include installing xcode (even if you don't plan on using xcode). After that the process will be:

1. Adding the xcode build tools: xcode-select --install
2. Adding OSS build libraries: brew install cmake
3. Installing 32blit tools: pip3 install 32blit
4. Installing the ARM cross-compile toolchain from https://developer.arm.com/tools-and-software/open-source-software/developer-tools/gnu-toolchain/gnu-rm/downloads (this could be done from brew, but I prefer a system-wide install)
5. Add the ARM tools directory to your current PATH. As an example, you can add ~/.zprofile and add export PATH="$PATH:/System/Volumes/Data/Applications/ARM/bin" at the end for the default install.
6. Clone 32blit SDK: git clone https://github.com/32blit/32blit-sdk.git
7. Change into the cloned directory and update submodules as needed: git submodule update --init
8. Clone Pico SDK: git clone -b master https://github.com/raspberrypi/pico-sdk.git
9. Change into the cloned directory and update submodules as needed: git submodule update --init
10. Clone Pico Extras: git clone -b master https://github.com/raspberrypi/pico-extras.git
11. Change into the cloned directory and update submodules as needed: git submodule update --init
12. Move all the SDKs into /opt (again, I'm a fan of system-wide installs)

Testing with SDL

To test on your local machine before copying to the PicoSystem, build an SDL port of your app with:

mkdir build.sdl
cd build.sdl
cmake ..
make

In macOS you can launch the app from the commandline with:

open PicoSystem\ Demo.app

Building for the PicoSystem

If you've got local copies of the Pico SDK, Pico Extras and 32blit SDK alongside your project, then you can configure and build your .uf2 like so:

mkdir build.pico
cd build.pico
cmake .. -D32BLIT_DIR=/opt/32blit-sdk -DPICO_SDK_PATH=/opt/pico-sdk -DCMAKE_TOOLCHAIN_FILE=/opt/32blit-sdk/pico.toolchain -DPICO_BOARD=pimoroni_picosystem
make

Copying your game to your PicoSystem

Connect your PicoSystem to your computer using a USB Type-C cable.

From a power-off state, hold down X (the top face button) and press Power (the button at the top left, next to the USB Type-C port).

Your PicoSystem should mount as "RPI-RP2". On macOS this might be /Volumes/RPI-RP2:

cp demo.app.uf2 /Volumes/RPI-RP2

The file should copy over, and your PicoSystem should automatically reboot into your game.