A modern OpenGL game engine with PBR rendering, a visual editor, and an ECS architecture.
- PBR Rendering — Cook-Torrance BRDF, Metallic/Roughness workflow, multi-pass pipeline (Shadow, GTAO, Bloom, SSS, SSR, Post-processing)
- Image-Based Lighting — Diffuse irradiance, specular prefiltering, BRDF LUT
- Visual Editor — ImGui-based scene editor with viewport, hierarchy, properties, asset browser, profiler, undo/redo, hotkeys;
- ECS Architecture — EnTT-powered with Transform, Renderable, Camera, Lighting, Hierarchy, AudioSource, AudioListener components
- Audio System — miniaudio integration; spatial audio; listener management
- Scene Management — Scene graph, JSON serialization, resource caching (glTF / FBX / OBJ / PLY / STL)
- RHI Abstraction — OpenGL backend, architecture ready for Vulkan / D3D12
The engine supports Forward and Deferred pipelines. Both use Cook-Torrance PBR with metallic/roughness workflow.
| Feature | Description |
|---|---|
| Shadows | Directional: 4-cascade CSM with PCF/PCSS; Point: cubemap depth (up to 4); Spot: 2D depth (up to 4). Shadow preview mode for debugging. |
| IBL | Diffuse irradiance cubemap, prefiltered specular env map, BRDF LUT; HDRI-based skybox |
| GTAO | Screen-space ambient occlusion with multi-direction ray march and bilateral blur |
| SSS | Subsurface scattering (BSSRDF-inspired wrapped diffuse) for skin/fabric; Forward pipeline via material subsurface option |
| Bloom | Brightness threshold extract, 6-level mip chain, separable Gaussian blur |
| SSR | Screen-space reflection (Deferred only); Hi-Z accelerated ray march; Fresnel and roughness modulation; composited in post-process |
| Post-process | AO blend, bloom add, Reinhard tonemapping, gamma correction |
| Display modes | Lit, Albedo, Normals, Metallic, Roughness, Material AO, Emissive, AO, Depth, SSR, Shadow preview |
Deferred pipeline adds G-Buffer (4 RTs + depth), Hi-Z, clustered light culling (compute) 、SSR. Forward pipeline uses direct PBR with full light iteration. Pipeline mode is configurable in Project Settings.
- OS: Windows / Linux / macOS
- Compiler: C++17 (MSVC 2017+, GCC 7+, Clang 5+)
- CMake: 3.20+ | OpenGL: 3.3+ | Python: 3.6+ (build scripts)
git clone --recursive https://github.com/Furry-Monster/RealmEngine.git
cd RealmEngine
# Build & run (Python script)
python scripts/build.py -t Release -j 8 -r
# Or manual CMake
mkdir build && cd build
cmake .. -DCMAKE_BUILD_TYPE=Release
cmake --build . --parallelAfter build, run bin/RealmEditor (or bin/RealmEditor.exe on Windows).
RealmEngine/
├── engine/ # Core engine library (RHI, renderer, ECS, platform)
├── editor/ # Visual editor (panels, commands, bridge)
├── sandbox/ # Standalone sandbox player
├── shaders/ # GLSL shaders
├── assets/ # Models, textures, HDR environment maps
├── libs/ # Third-party dependencies (git submodules)
├── scripts/ # Build, format, lint, test scripts
└── CMakeLists.txt
All managed as git submodules in libs/:
GLFW | GLAD | GLM | Assimp | spdlog | ImGui | ImGuizmo | stb | EnTT | miniaudio | nlohmann/json
python scripts/build.py --help
# Common usage
python scripts/build.py # Debug build
python scripts/build.py -t Release -j 8 # Release, 8 jobs
python scripts/build.py -c -r # Clean, build, run
python scripts/build.py --no-editor # Skip editor
python scripts/build.py --no-sandbox # Skip sandbox
python scripts/build.py --tests # Enable tests
# Code quality
python scripts/format.py # clang-format
python scripts/lint.py # clang-tidySee scripts/GUIDE.md for full build documentation.
MIT License — see LICENSE.
Issues and Pull Requests are welcome.