Show HN: Horizon Engine – C++20 3D FPS Game Engine with ECS and Modern Renderer
bhdr26k Saturday, January 10, 2026Hi HN,
I’m working on an experimental 3D FPS game engine in C++20, aiming to deeply understand engine internals from first principles rather than just using existing frameworks.
Currently I'm strictly following LearnOpenGL docs.
This project focuses on: Entity-Component-System (ECS) architecture for high performance. OpenGL 4.1 rendering with a PBR pipeline, material system, HDR, SSAO, and shadow mapping. Modular systems: input, physics (Jolt), audio (miniaudio), assets, hot reload. A sample FPS game & debug editor built into the repo.
Repo: https://github.com/jackthepunished/horizon-engine
This isn’t intended to be a commercial rival to any commercial game engines.
it’s a learning and exploration project: understanding why certain engine decisions are made, and how to build low-level engine systems from scratch.
I’m especially looking for feedback on: Architecture choices (ECS design, render loop, module separation) Your thoughts on modern C++ engine patterns
What you’d build vs stub early in a homemade engine
Tips from experienced graphics/engine developers Criticism and suggestions are very welcome — it’s early days and meant to evolve. Thanks for checking it out!