Projects

I’m making a device to water my basil plants. Whilst working on this, I encountered an issue where running the pumps whilst connected to WiFi would crash the microcontroller. After investigation, I found the cause was poor grounding and Electromagnetic Interference (EMI).

Ten years ago today, I uploaded the first version of Capture The Flag. Capture The Flag is a multiplayer game where two teams of players battle to claim the other team’s flag whilst defending their own. Capture The Flag is played in a destructible voxel environment, allowing players to build defences and place traps.

Capture The Flag started life as a persistent kingdoms game but quickly pivoted to a match-based team game. It was developed iteratively, taking into account player feedback. I hosted a server for the game for many years and a community formed around it. In 2021, I handed over the reins to CTF to very capable hands; it remains Minetest’s most popular server to this day.

This article covers the history of CTF, the lessons I learned, and the changes I made along the way.

One of the reasons I learned how to program was to make games. Games are a unique form of creative medium, combining art, interactive storytelling, and vibrant worlds. But as a software engineer, it’s easy to lose sight of my goals and get trapped by the technical details. It’s common for software engineers in game dev to roll their own engine, which I believe reduces productivity and is ultimately a distraction to making a game.

Note that I’m not just referring to making reusable or generic game engines; for this article, I consider using low-level technology like OpenGL, SFML, or SDL to make games to include the act of rolling your own game engine, even if the focus is specific. It’s more manageable, but you still end up reinventing the wheel and having to solve many of the same problems.

There are plenty of other articles about whether or not to make your own game engine. This article is personal to me; it’s an exploration of my journey in game dev, a discussion of what motivates me, and a promise for the future.

In 2020, the Minetest Discord community ran a mod-making competition with “combat” as the theme. Participants had one week to create a mod with all the code written within the time, but pre-existing art was allowed. I made a Real-Time Strategy (RTS) minigame called Conquer; it received first place.

In this article, I will discuss some of the interesting challenges that Conquer needed to solve. I believe that Conquer is a great example to learn from as it demonstrates best practices for Minetest modding; it is well-structured and unit-tested.

My eventual goal with electronics is to create autonomous robots and drones; I’d like to make a quadcopter with my own flight controller that can take off, land, and follow a target. This will be quite an ambitious project, and I’m nowhere near capable enough for that yet.

Previously, I created a simple plant monitor that reported stats to an online dashboard. This allowed me to learn soldering, stripboards, and 3d printing. To work on future projects, I need to be able to produce ever more complicated circuits and mechanical designs.

After watching some Lock Picking Lawyer on YouTube, I was inspired to think about different locking mechanisms. A locking box would be a good experiment with mechanical design, and if combined with IoT, would be good for electronics too.

In this article, I will cover how I created my lock box - from the problems I had, the iterations I made, and the final design I settled on. It’s a bit of a random project, I didn’t have set goals in mind. I started by exploring different locking mechanisms, and then moved to focusing on the electronics and getting it working.

In 2016, I created an app to install mods for Minetest’s Android port. It was my first Android app; it taught me a great deal about Android development and also helped me get my first programming job.

Minetest is an open-source game engine with millions of downloads and thousands of weekly players. The project has a very active modding community, with many games available to play. Before I created the app, users had to manually install content by unzipping their files into a directory; this was a poor user experience, especially on Android, so I created the app to make this easier.

Minetest now has ContentDB, a platform I created to browse and install mods and games within Minetest. Because of this, the app is now obsolete and is no longer available for download. That doesn’t mean this app is fully gone - the lessons I learned live on in ContentDB.

I created Renewed Tab last year to fulfil my personal needs, and have since expanded on it based on user feedback, focusing on rich widgets, a clean user experience, and customisation.

I wrote an article on the Renewed Tab blog where I explained what led me to create a New Tab extension and what the design requirements were.

In 2018, I had the opportunity to create a web app for University coursework, as a solo project. I chose to create a package repository for Luanti, an open-source project I help maintain.

Luanti (formerly Minetest) is an open-source game engine with millions of downloads and thousands of weekly players. The project has a very active modding community, and many available games to run. There was one big issue - you had to manually install mods and games by unzipping their files into a directory. This was a very poor user experience.

In April 2021, I participated in my first game jam, Ludum Dare 48. Ludum Dare is a popular online game jam; this event received over 3800 submissions. The theme was “Deeper and Deeper,” and I created a game where you manage a tin mine.

The year is 1790, and the Cornish tin industry is booming. You are a businessperson who has just secured investment to build a mine. The area is known to be rich in tin, which is in high demand.

Rather than controlling your workers directly, you drag out plans for tiles to be mined and built. The workers will mine tunnels and build where ordered. They will carry mined resources to the surface to be sold.

I have a lot of houseplants, but I often forget to water them. I’ve been getting into electronics and thought this would be a great opportunity to make something.

I made a plant monitor, which measures soil moisture, temperature, and humidity, and reports these things to a cloud IoT service called Thinger.io.

I worked as an Android developer just over two years ago, creating native apps for clients using Java and Kotlin. During that time, Kotlin was gaining prominence and had just been made official by Google. Google also introduced Architecture Components that year, later renamed to JetPack. Since then, the Android ecosystem has changed significantly, with Kotlin and JetPack gaining significant maturity and development. Out with Realm, Activities, and Model-View-Presenter (MVP), in with Room, fragment-based architecture, and MVVM. Data-binding and MVVM are pretty awesome and breathe a whole new life into Android app development.

I wrote a raytracer and a rasteriser as part of my university course. The raytracer supported features such as indirect lighting, reflection, refraction, and a photon mapper capable of simulating the final positions of 60,000,000 photons in a few minutes (and quite a few GBs of RAM).

I wrote a Bash script to sort git commits into buckets, to be used as the first step of making a change log. It supports rewording commit messages, can be stopped and resumed, and supports automatic filtering based on keywords.

During the second year of university, I created a kernel for the ARMv7 instruction set. I went above and beyond what was required on this project, achieving a clean design and features such as a blocked process queue, piping, kill, and a simple filesystem. This was my favourite coursework so far. I found it very interesting to learn about and implement the things that we take for granted as programmers.

I tried to stick to POSIX as much as possible, and stuck to the Linux method of having everything as either a file or process. Because pipes and standard in/out were both “files”, I was able to implement both popen and piping of the output of a process to another process.

For the last two years, I have been working on a very ambitious game. The game is a top-down sandbox with multiplayer support. I’m aiming towards a city-based game, where players can wander around a procedurally generated city. One of the main reasons I started creating this game is to learn about multiplayer networking at a low level - client-side prediction, server-side reconcilliation, cheat preventation, and reducing the visual effect of latency.

This article will show you how to verify a user’s identity by letting them associate their account with an external third party phpBB account. I used Python and Flask to achieve this, however any language and framework should work, and shouldn’t be too hard to port to.

I recently wrote and released a python module to allow fetching of profile data.

You can install it using pip:

pip install beautifulsoup4 phpbb-parser

Here’s how you import and use a profile:

import phpbb_parser as parser

username = "rubenwardy"
profile = parser.get_profile("https://forum.minetest.net", username)

if profile:
    signature = profile.signature.text
    location = profile.get("location") or "unknown"
    github = profile.get("github") or "none"

    print(username + " from " + location + " has github " + github)
    print("Signatue: " + signature.text)
else:
    print("Could not get profile!")

profile.signature is a beautifulsoup4 object.

Next: Linking a user account to an external phpBB forum.

To get more than 50% on our coursework, you had to submit extensions. Here are some of my favourite ones.

I was contacted by a client to create a system which calculates the workload for employees based on their assignment to tasks and appointments.

The system needs to solve two problems: Firstly, different staff members work different numbers of hours, which makes it hard to allocate tasks fairly and proportionally. Secondly, the client wanted to use the system to analyse past workloads and to anticipate future workload, in order to improve her system of work.

Hello 2015! Recently I have created an implementation of the 3D projection algorithm. It is just wireframe models. It works pretty well, except it doesn’t do frustum culling. You still see things that are behind you, but upside down.

The source code of this implementation is available under the WTFPL or CC0 licenses - you can choose which one you want to use. Use WASD to move, arrow keys to rotate, space to ascend and shift to descend.

Hi all! I’m back again for another post. This time I am going to show off a project I have had for quite a while - it is a cellular automaton which simulates the Lotka Volterra equations.

Just a short post this time - I have created some widgets for the chess website Lichess. I was quite surprised that these did not exist yet, in any form. Luckily Lichess exposes an API to use. You can have a look at them by clicking the link below.

Recently I have been looking at languages and compilation: VMs, parse trees, lexers, and interpreters. Nand to tetris is a pretty awesome guide to how the CPU executes programs - from logic gates to high level languages.