A sample program for Retr68

... with a special focus on demonstrating a Nix-based build setup.

Install Nix

First, make sure you have Nix installed. If you're not on NixOS and you haven't already installed Nix, I recommend the Determinate Nix Instlaler, a third-party installer for the Nix package manager: https://install.determinate.systems/.

Set Up Binary Cache (optional)

A binary cache will save you from compiling all of Retro68 yourself if it has already been built by a CI build. The binary cache currently contains binaries for x86_64 Linux and for x86_64 macOS Apple Silicon users are out of luck for now as there is a shortage of free build servers for that platform. You can skip this step.

First, install Cachix according to the instructions at https://www.cachix.org/

Then, run cachix use autc04 to set up your system to use the autc04 binary cache from cachix.org.

Update the lockfile

The flake.lock file defines what version of Retro68 is being used. Use the nix flake update command to update everything to the newest version.

Running a complete build

You can build the entire project from scratch using the nix build command. The output can be found as a MacBinary file in the result directory created by that command.

By default, a fat binary (a combination of M68K and PowerPC code) is created. You can also use nix build .#m68k or nix build .#powerpc to build only for one architecture.

Entering a dev shell

Use nix develop to enter a development shell with tools for 68K development. Alternatively, use nix develop .#powerpc to get a developmnet shell with PowerPC tools instead.

Build using CMake

In your development shell, environment variables are automatically set up so that you do not need to set a toolchain file for CMake:

mkdir build
cd build
cmake .. -G Ninja
ninja

Install DirEnv (optional)

Direnv is a tool that will automatically set up the Nix development shell as soon as you change into this directory. See https://direnv.net/.

After installing it according to the instructions, use the direnv allow command to tell direnv that it is allowed to trust this directory.

Direnv in VS Code (optional)

This workspace recommends the Martin Kühl's direnv extension; this extension uses direnv (if installed) to provide the development environment to commands run by VSCode.

With this installed, you should be able to use vscode's built-in CMake support to build your code from the IDE.