Repository Name

This repository contains the GNC FSW algorithms.

Getting Started

This repository has two primary usages and therefore two build paths:

1. To compile the FSW algorithms as modules for the Ximera simulation tool.
2. To compile the FSW algorithms for the GNC target platform.

The build Ximera build path is controlled by the Ximera build system. It expects the directory structure:

• algorithms/
  • msgPayloadDef/
  • alg1/
    • module.i
    • module.h
    • module.cpp
  • alg2/
    • etc.

The flight software build path is controlled by the CMake build system and associated cmake files in this repository. This build path is described below.

Dependencies:

• Eigen for freestanding C++ (it's assumed that the repo is at ../ relative to this repo)

Required Tooling:

• GCC 13.3.1 or higher
• CMake 3.24 or higher
• Python 3.10 or higher

Linux

1. Install GCC 13.3.1 with sudo apt install gcc-13
2. Test GCC with gcc --version - this command should output information about the installed GCC compiler.

If you want to set GCC 13 as your default compiler;

# Add the compiler versions to the alternatives system
sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-X.Y PRIORITY
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-X.Y PRIORITY
# Replace X.Y with version number and PRIORITY with a numerical value (higher is preferred e.g. 100)

# Configure the default compiler interactively
sudo update-alternatives --config gcc
sudo update-alternatives --config g++

Mac OS

1. Install homebrew
2. Install GCC 13.3.1 with brew install gcc@13
3. Test GCC with gcc --version - this command should output information about the installed GCC compiler, including its version number.

Using Build.sh

build.sh — drives builds via CMakePresets.json

Examples:
  ./build.sh --list
  ./build.sh linux-gcc-debug/release
  ./build.sh macos-gcc-debug/release
  ./build.sh riscv32-gcc-debug/release (this option only works on Linux with installed cross compiler)
  ./build.sh --configure linux-gcc-debug --build linux-gcc-debug --fresh
  ./build.sh macos-gcc-debug --archive lib/libgncAlgorithms.a

Notes:
- Uses your CMakePresets.json configure/build presets.
- --fresh uses CMake's native reconfigure (CMake >= 3.24).
- The script chooses a sensible default preset if none is provided.

One can add a user-defined preset to CMakeUserPresets.json which is not added to the repository. E.g.

{
  "version": 5,
  "cmakeMinimumRequired": {
    "major": 3,
    "minor": 24,
    "patch": 0
  },

  "configurePresets": [
    {
      "name": "with-eigen",
      "inherits": "macos-gcc-debug",
      "cacheVariables": {
        "EIGEN3_DIR": "/Users/joe/eigen"
      }
    }
  ],

  "buildPresets": [
    {
      "name": "with-eigen",
      "configurePreset": "with-eigen",
      "verbose": true
    }
  ]
}

Agent Instructions

For AI agents, please refer to AGENTS.md for direction on using project conventions and workflows.