A high schooler built a 100,000-line open-world RPG from scratch to learn OpenGL
Hedra is a 3D open world game I wrote from scratch while in highschool
Project Hedra is an open-world, low-poly RPG with procedurally generated worlds, quests, bosses, classes, and skills, built on a custom engine featuring modern OpenGL rendering, screen-space reflections, ambient occlusion, and a Python scripting API. The developer started it at 15 to learn OpenGL; scope creep turned it into a full game and engine with roughly 100k lines of code and first-class Linux and Windows support.
The game only supports loading .PLY and .DAE models, both which are in plaintext and the models have no textures. Therefore if you put this into perspective, this means I wrote a bunch of text that reads text and creates interactive images from this. I think this is pretty cool.