windokk.dev

C++ Custom Game Engine : Shard Engine

November 20, 2025

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Technical Sheet :

Type: 3D Game Engine
Creation Date/Duration: 2025/2026, 1 year
Tools : VS Code | Cmake | C++ | Open GL | Vulkan | Jolt Physics
Project Summary : Shard is my current personnal game engine, written from scratch (using some libraries) on my free time. It includes a 3D PBR renderer, an editor, a level system, and a lot of other things. It is still in active development.
Project Goal : Design, Organize and Code a game engine in C++

It features :

Architecture

A clean, organized, and modular architecture
A platform abstraction layer (windowing, filesystem, threads, networking, crash reporting), running on Windows and Linux
A filesystem abstraction layer and a dynamic resource management system
Hot reload of the game module and of resources while the editor is running

Rendering

A customizable 3D PBR rendering engine with dynamic lights, MSAA, double-sided materials and an HDR pipeline with a tonemapper (exposure and tonemapper settings per world)
A render hardware interface (RHI) with Vulkan and OpenGL 4.6 backends, plus a null backend for headless runs
A render graph that schedules the passes, with a depth prepass and per-pass GPU timers
A render thread that draws in parallel with the simulation, fed by snapshots of the scene
Probe-based global illumination, baked lightmaps (with automatic lightmap UV generation), and a path-traced mode for reference renders
Billboards, with instanced rendering, an atlas, and editor icons
BC7 / BC5 / BC4 texture compression with an on-disk cache, plus texture size limits to save video memory

Gameplay and systems

Integration of various libraries: FMOD for audio (3D positional sound), Jolt for physics (rigid bodies and collisions)
Input for keyboard, mouse and gamepads (dead zones, rumble)
FBX model import (ufbx)
A reflection system for components, with tooltips on fields and JSON serialization
A level system with a hierarchical structure: Levels → Actor → Component
A scripting API (currently C++ only)

Editor and tooling

An editor built using ImGui (supports a “game” preview mode and game module loading), with a scene hierarchy, gizmos, thumbnails, project settings, and a prompt to save unsaved levels before playing
A developer console with variables and commands, scriptable for stress tests
A headless runner with a deterministic mode, input recording and replays, and a dedicated server mode
Automated tests, a smoke test, a stress test and a benchmark, all run in CI on Windows and Linux

The engine is open source and available on GitHub.