Gravity Simulator
As part of A-level computer science, we do an extended coursework project over the course of about 9 months.
I decided to make a 3D gravity simulator.
I used C# as the programming language, and used OpenGL for the 3D graphics.
Learning about shaders and transformations and all the things required to make 3D graphics work was really interesting, and something I'd never done before.
The UI was created using a graphics library called Dear ImGui, which, once integrated, allowed me to create UI elements extremely easily.