dotnet-bluetooth-le VS BleWinrtDll

- Comes with ready-to-use models and textures

To generate roads, I downloaded .gpx files from my Strava activities, then implemented a parser to take coordinates and elevations and build roads in-game using EasyRoads3D. These tools combined worked quite well but required some manual work. I had to go over the entire length of the road to smoothen it up (due to GPS noise in .gpx files). The terrain also didn’t always perfectly align with the road, so I had to manually modify it.

I figured that steering would be a good way to keep the user engaged in the gameplay, instead of just sitting on the bike and pedalling. With required steering, you need to be engaged to not drive off the road.

There are some solutions to virtual steering in other smart trainer games, but they are hardware-based - e.g., for Zwift, you need to buy their hardware controller. I really wanted to keep it as simple and inexpensive as possible, so I used a smartphone mounted to the handlebars as a steering controller.

I implemented native apps for both iOS and Android. They use the gyroscope to get the steering value and broadcast it as a BLE peripheral. Implementing Bluetooth in Unity was a little tricky as there is no built-in solution. The implementation depends on the platform the game is running on. It boils down to writing a native plugin for each platform you support.

For macOS, there is an open-source library written in Swift - https://github.com/codeinversion/sensors-swift. It already has the necessary services and characteristics implemented. I had to modify it a little and compile it into a Unity plugin.

For Windows, there also is a library - https://github.com/adabru/BleWinrtDll, but it wasn’t working too well. Because I targeted UWP, I was able to implement my own Bluetooth logic in C# and compile it directly in Unity.

Overall, it was a really fun project to work on. I’m particularly happy that I was able to release it starting from scratch in just a couple of months, and I hope to continue working on it.

Using the absolutely wonderful BLE dll for Unity (https://github.com/adabru/BleWinrtDll/)

Looking at the image on the BleWinrtDll GitHub page, my understanding is that when I subscribe to a device, I should be able to see the data under the “Subscribe” button, which is in a text field labeled “characteristic value” within the editor.