🌟 RayTrophi - Advanced Real-Time Ray Tracing Engine

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A high-performance, production-ready ray tracing renderer with hybrid CPU/GPU rendering

▶️ Watch Showcase on YouTube

Features • Quick Start • Architecture • Performance • Gallery

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📖 Overview

RayTrophi is a state-of-the-art physically-based ray tracing engine designed for architectural visualization, product rendering, and real-time graphics. It combines the flexibility of CPU rendering with the raw power of GPU acceleration through NVIDIA OptiX.

🎯 Key Highlights

• Hybrid Rendering: Seamlessly switch between CPU (Embree/Custom BVH) and GPU (OptiX & Vulkan) acceleration

• Production-Ready: Principled BSDF, advanced materials, volumetrics, subsurface scattering

• High Performance: Optimized BVH construction (<1s for 3.3M triangles), 75% memory-optimized triangle structure

• Real-time Preview: Modern interactive UI with ImGui, animation timeline

• Industry Standard: AssImp loader supports 40+ 3D formats (GLTF, FBX, OBJ, etc.)

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📊 Project Statistics

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| Metric | Value | | :--- | :--- | | Files (Source) | 249 | | Lines of Code | 136,184 | | UI Control Points | 1,015+ | | Last Updated | 2026-03-10 |

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Full Technical Report: ARCHITECTURE.md

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✨ Features

🎨 Rendering Capabilities

• Materials

  • ✅ Principled BSDF (Disney-style uber-shader)
  • ✅ Lambertian, Metal, Dielectric
  • ✅ Volumetric rendering with noise-based density
  • ✅ Subsurface Scattering (SSS)
  • ✅ Clearcoat, Anisotropic materials
  • ✅ Hair System: GPU-accelerated hair rendering and simulation

• Lighting

  • ✅ Point lights, Directional lights
  • ✅ Area lights (mesh-based)
  • ✅ Emissive materials
  • ✅ HDR/EXR Environment Maps (equirectangular projection)
  • ✅ Global Volumetric Clouds:
    • Any Sky Mode: Decoupled rendering works seamlessly with HDRI, Solid Color, or Nishita Sky.
    • Physical Scattering: Henyey-Greenstein phase function with controllable Anisotropy (Silver Lining).
    • High Quality: Adaptive ray marching (up to 128 steps) and jittered sampling to eliminate banding artifacts.
    • Dynamic Control: Wind/Seed offsets, Coverage, Density, and Altitude layers.
    • Soft Horizon: Smart density fading prevents black horizon artifacts.
  • ✅ Advanced Nishita Sky Model:
  • Physical atmosphere (Air, Dust, Ozone, Altitude) matching Blender concepts.
  • Day/Night Cycle: Automatic transition with procedural stars and moon.
  • Moon Rendering: Horizon size magnification, redness, atmospheric dimming, and phases.
  • Sun Glow: High Mie Anisotropy (0.98) for realistic sun halos.
  • Light Sync: Automatically synchronizes Scene Directional Light with Sky Sun position.)
  • ✅ Soft shadows with multiple importance sampling

• Advanced Features

  • ✅ Accumulative Rendering: Progressive path tracing for noise-free, high-quality output
  • ✅ Adaptive Sampling: Intelligent sampling engine focusing on noisy areas
  • ✅ Depth of Field (DOF)
  • ✅ Motion Blur
  • ✅ Intel Open Image Denoise (OIDN) integration
  • ✅ Tone mapping & post-processing
  • 🧪 [EXPERIMENTAL] Vulkan RT Backend (Active Development): Hardware ray tracing pipeline built on Vulkan Ray Tracing (VK_KHR_ray_tracing_pipeline). Features GPU-accelerated skeletal animation via compute skinning shaders, TLAS/BLAS refit for dynamic geometry, persistent descriptor sets, and a single-submit trace+readback command buffer. Gracefully falls back to OptiX or CPU if Vulkan dependencies (vulkan-1.dll) or a compatible GPU are absent.
  <details> <summary>🧪 <b>Vulkan Backend — Feature Compatibility</b> (expand)</summary>

  | Feature | OptiX | Vulkan RT | Notes | |---------|:-----:|:---------:|-------| | Principled BSDF | ✅ | ✅ | Full parity | | Lambertian / Metal / Dielectric | ✅ | ✅ | Full parity | | Subsurface Scattering (SSS) | ✅ | ✅ | Minor colour tint difference | | Clearcoat & Anisotropic | ✅ | ✅ | Full parity | | Volumetric Rendering | ✅ | 🧪 | Minor density differences | | Hair System | ✅ | 🧪 | Shader computation differences | | HDR / EXR Environment | ✅ | ✅ | Full parity | | Nishita Sky & Day/Night Cycle | ✅ | ✅ | Full parity | | Volumetric Clouds | ✅ | 🧪 | Minor scattering differences | | Water / Ocean (FFT) | ✅ | 🧪 | Wave reflection differences | | Skeletal Animation (GPU Skinning) | ✅ | ✅ | Vulkan compute shader | | Depth of Field (DOF) | ✅ | ✅ | Full parity | | Motion Blur | ✅ | ✅ | Full parity | | Soft Shadows (MIS) | ✅ | ✅ | Full parity | | Area Lights | ✅ | ✅ | Full parity | | Tone Mapping & Post-FX | ✅ | ✅ | Full parity | | OIDN Denoising | ✅ | ✅ | Full parity | | Adaptive Sampling | ✅ | ✅ | Full parity | | Progressive / Accumulative Render | ✅ | ✅ | Full parity |

  Legend: ✅ Full support  |  🧪 Supported, minor output differences possible

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  • ✅ Advanced Animation:
    • Bone animation with quaternion interpolation
    • Multi-track timeline with keyframe editing (Location/Rotation/Scale/Material)
    • Batch Animation Rendering: Export animation sequences to image files with material keyframe support
    • Cancellable renders with "Stop Animation" button
    • Real-time playback preview with scrubbing
  • ✅ Advanced Cloud Lighting Controls:
    • Light Steps control for volumetric cloud quality
    • Shadow Strength for realistic cloud shadows
    • Ambient Strength for cloud base illumination
    • Silver Intensity (Silver Lining) for sun-edge effects
    • Cloud Absorption for light penetration control
  • ✅ Full Undo/Redo System (v1.2):
    • Object transforms (move, rotate, scale)
    • Object deletion and duplication
    • Light transforms (move, rotate, scale)
    • Light add/delete/duplicate
    • Keyboard shortcuts: Ctrl+Z (Undo), Ctrl+Y (Redo)
  • ✅ Advanced Selection System (NEW v1.3):
    • Box Selection: Right-click drag to select multiple objects
    • Mixed Selection: Select lights + objects together
    • Ctrl+Click: Add/remove from selection
    • Select All/None buttons: Quick selection in Scene panel
    • Multi-object transform: Move multiple selected items at once
  • ✅ Idle Preview (NEW v1.3):
    • During gizmo manipulation, pause mouse for 0.3s to preview position
    • See render result before releasing - adjust if needed
    • Blender-like UX for precise positioning

🚀 Performance & Optimization

• Multi-BVH Support

  • Embree BVH (Intel, production-grade)
  • Custom ParallelBVH (SAH-based, OpenMP parallelized)
  • OptiX GPU acceleration structure
  • 🧪 Vulkan RT TLAS/BLAS architecture — dynamic refit, compute skinning, single-submit pipeline (Experimental)

• Optimizations

  • SIMD vector operations
  • Multi-threaded tile-based rendering
  • Progressive refinement
  • Memory Optimization: Triangular footprint reduced from 612 to 146 bytes (75% reduction)
  • Robust Texture System: Crash-proof loader for Unicode paths and corrupted formats
  • Cached Texture Management (Optimized Hit/Miss logic)
  • Deferred BVH Update (NEW v1.3): Gizmo manipulation doesn't block - BVH updates only when needed
  • O(n) Multi-Delete (NEW v1.3): Delete 100+ objects instantly (was O(n²))

🖥️ User Interface

• Modern ImGui-based Dark UI with Docking
• Animation Timeline:
  • Multi-track visualization with group hierarchy (Objects/Lights/Cameras/World)
  • Per-Channel Keyframing: Separate Location/Rotation/Scale keyframes
  • Expandable L/R/S sub-channels with color coding
  • Context menu for insert/delete/duplicate operations
  • Drag-to-move keyframes, zoom/pan/scrub navigation
• Render Quality Presets (Low, Medium, High, Ultra)
• Dynamic Resolution Scaling
• Scene hierarchy viewer and Material editor

📦 Asset Browser & Library System

• Metadata-driven asset discovery for model, anim_clip, vdb, and vdb_sequence
• Hybrid library workflow: built-in project assets root plus user-added local libraries
• Extended VDB / VDB sequence metadata with grids, bounds, shader presets, and sequence info
• Asset cards with preview/thumbnail cache, favorites, tags, and saved collection/smart-folder presets
• Drag-and-drop scene placement with viewport ghost preview and auto-selection of the newly appended object
• Project-scoped UI persistence for asset browser layout, library list, and saved collection filters
• Performance metrics (FPS, rays/s, memory usage)
• Box Selection: Right-click drag for multi-selection
• Transform Gizmo Idle Preview: Pause during drag to preview position

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�️ Procedural Tools & Systems

🏔️ Advanced Terrain Editor

<img src="docs/images/terrain_header.jpg" width="100%" alt="Terrain Editor System">

• Sculpting Brushes: Intuitive brushes for raising, lowering, smoothing, and flattening terrain geometry in real-time.
• Hydraulic & Fluvial Erosion:
  • Simulate realistic water flow and sediment transport
  • Create natural-looking riverbeds and valleys automatically
  • Control erosion strength, rain amount, and solubility
• Heightmap Support: Import/Export 16-bit heightmaps for external workflows (World Machine, Gaea).
• Node-Based Workflow: