Ifrit-v2

A collection of personal real-time rendering and simulation experiments.

Subprojects covered:

• Software Renderer: CUDA/Multithreaded CPU rasterizer & ray-tracer with JIT compilation
• Experimental Rendererer:
  • Syaro: Deferred renderer with Nanite-inspired cluster-based level of detail
  • Ayanami: Global illumination using probes and software ray tracing

Important

This repository contains the master branch for Project Ifrit v2, the further development has been moved to a private repository due to the force majeure. I will keep the current repository synchronized with the development repository as far as possible.

To access the development repository, please contact me: funkybirds@outlook.com

Soft Renderer / Mesh Shading	Soft Renderer / CUDA Renderer
Syaro / Cull Rasterize Visibility Buffer (R32_UINT)	Syaro / Final Output
Syaro / Timing	Soft Renderer / Derivatives
Ayanami / GDF Object Grids + Surface Cache Lookup*	Ayanami / Global Distance Field (GDF)*
Aria / Volumetric Lighting	Artemis / Bi-Level Marching Cubes (I3D 2024)
Soft Renderer / Profile (Nsight Compute)	Ayanami / Debug (Hierarchical Tracing, Incomplete) * (RenderDoc)

📸 See GALLERY.md or docs/img subfolder for more screenshots
🎥 View Syaro's LoD transitions: docs/img/syaro_lod.mkv

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About This Project

This repository succeeds my previous rendering projects:

• Aria: WebGL2 and Vulkan experiments
• Ifrit-v1: Java-based console renderer
• Iris (C# / C++): Tiny Renderer implementation

✨Features Supported

Parallelized Soft Renderer

• Parallelized rasterization & ray-tracing pipeline, with GPU (CUDA) & Multithreaded CPU (SIMD) support
• Support mesh shading pipeline (mesh shaders), and raytracing shaders (like miss shader)
• Support just-in-time compilation of HLSL SPIR-V shader code.
• Covers culling (including contribution culling), MSAA (8x), mipmapping, anisotropic filtering and shader derivatives (ddx & ddy)
• Support texture sampling & cube mapping and texture lods.
• For implementation details and performance, check here

Experimental Renderer

Refactored version for my original renderer, improving pass management, synchronization primitives and descriptor bindings.

• Render Hardware Interface (RHI)
• Render Dependency Graph (RDG)
• Modern Graphics API Features: Bindless Descriptors, Dynamic Rendering ...
• Miscellaneous Utilities: Task System, Shader Variants, Texture Compression Supports ...
• Reflection & Hybrid Serialization Support: Reflection-based Editor

Subproject Syaro

• Reproduced some features mentioned in Nanite's report: Two-pass occlusion culling, Mesh LoDs, Compute-shader-based SW rasterization, Simple material classify pass.
• Some extra features supported: Horizon-Based Ambient Occlusion (HBAO) / Cascaded Shadow Mapping (CSM) / Temporal Anti-aliasing (TAA) / Convolution Bloom

Subproject Ayanami*

• Distance Field Generation: Distance Field Shadow Culling / Distance Field Soft Shadow (DFSS) /BC4 Compression
• Surface Cache: Object Grids (Global Distance Field Attribute Lookup)
• Lighting Probes: Adaptive Screen Space Probe Placement / Screen Probe Tracing
  • Screen Space Tracing (SSGI+HiZ)
  • Mesh/Global Distance Field Tracing (Grid Cull+Ray Marching)

Subproject Artemis**

• Procedural Surface Reconstruction From Particles

Note

*. Ayanami is still an incomplete project for I am working on projects with higher priority. These features might be severely unstable and time-consuming. For problems and details, refer to CHANGELOG.md TODO.md

**. Other features are available only in development branch now.

⚡️Quick Start

Caution

Some breaking architectural changes are scheduled in dev branch for the following consideration:

• Rendering Parallelization (including refined task graph, parallelized RDGs, async compute, resource streaming and RHI translation thread). Old RHI abstraction has been largely modified. See TODO.md for the roadmap.

All downstream modules will be temporarily (and some will be permanently) removed. Please checkout latest checkpoint/v* branch before going on. Current dev branch does not contain interactive demos.

1. Clone Repository

git clone https://github.com/Aeroraven/Ifrit-v2.git --recursive 

2. Install Dependencies

• CMake 3.25+

• MSVC 19.29+

• Python 3

• libclang 19

• Vulkan SDK 1.3.296+

  • Core 1.2 features (required)

  • EXT_mesh_shader extension (optional¹)

  • EXT_shader_atomic_float extension (optional¹)

  ¹ Device Compatibility:

  Subproject	RTX 3070 Ti	GTX 1050
  Syaro	✅	❌ (No mesh shader)
  Ayanami	✅	❌ (No mesh shader)
  Artemis	✅(Dev Branch Only)	✅(Dev Branch Only)

3. Build

bash Setup.sh --clang-root /path/to/clang

🧱Architecture

The source files can be decomposed into following parts.

Module Name	Functionality
ifrit.core	Basic definitions, logging, dynamic reflection and serialization, typing utilities (like compilation time utils) (Dependency: spdlog)
ifrit.core.math	Helper functions for SIMD and performance-oriented intrinsic Basic linalg supports
ifrit.demo	Demo
ifrit.display	Platform-specific window support Provides view layer for renderers, like console display for soft renderer (Dependency: glfw3)
ifrit.editor	Editor subsystem and debugging components for runtime Debug purpose only (Dependency: imgui)
ifrit.external	External dependencies building (Dependency: fsr2)
ifrit.geomproc	Algorithms for geometry processing, and CPU acceleration structures Including mesh cluster culling data generation, mesh tetrahedralization, mesh auto-lod and mesh-level signed distance field generation (Dependency: metis,meshoptimizer,openvdb,tetgen)
ifrit.ircompile	Backend for JIT runtime (Dependency: llvm)
ifrit.imaging	Utilities for image processing Including some texture compression utilities. (Dependency: ktx)
ifrit.profiler	Debugging Utilities (Dependency: renderdoc)
ifrit.reflparser	Tool for code parsing for ifrit.core/reflection utilities. (Dependency: llvm/libclang)
ifrit.rhi	Backend-agnostic render hardware interface.
ifrit.runtime	Implementations of renderer. Basic supports for mesh, assets, components and rendering
ifrit.shadercompile	Backend for shader compilation Contains glslc and slang backend (Dependency: glslc,slang)
ifrit.softgraphics	Implementation of soft renderer, with both MT-CPU and CUDA version (Dependency: cuda)
ifrit.vkrhi ifrit.vkrhi2	Vulkan backend (Dependency: vulkan)

📌Future Plans

See TODO.md for more details.

📌References & Acknowledgements

See ACKNOWLEDGEMENTS.md for more details.

This project draws inspiration from modern rendering techniques and research papers. While influenced by industry presentations (including Unreal Engine's technical talks), all code is original implementation to maintain license compatibility.

Special thanks to interviewers and mentors who provided valuable feedback during my internship applications—many suggestions have been incorporated into the roadmap.

Important

This repository does not (and will never) contain things including work-related content or confidential codes. All codes inside this repository are not related to any third-party individuals or affiliated groups, entities and companies.

📌License

Main Repository: AGPL-v3 License (or later)

This repository includes external dependencies under AGPL-3.0. Dual licensing available with contributor consent.

Contact Me: You can directly open the issue in this repo! Or use email above.