3D-Fractals

3D-Fractals is an educational, experimental 3D raymarching renderer written in C# using OpenGL, Silk.NET, and ImGui. The project started as a learning exercise focused on rendering 3D fractals, but gradually evolved into a more complex real-time raymarching demo with scene editing, serialization, and GPU-side acceleration structures.

This project is not production-ready. The architecture is experimental and optimized for learning and exploration.

Overview

• Real-time raymarching renderer

• Fully GPU-based rendering (fragment and vertex shader only)

• Support for classical SDF primitives and complex 3D fractals

• Interactive camera and scene manipulation via ImGui

• Scene and player serialization to JSON

• BVH acceleration structure transferred to the GPU via SSBO

• The renderer is intentionally flexible: shaders are stored as external .glsl files and can be freely modified to implement alternative raymarching or rendering techniques.

Features

Rendering

• Fragment-shader-based raymarching

• Signed Distance Field (SDF) evaluation

• Soft shadows

• Simple global illumination model (sun-like directional light)

• Euler-based object rotation

• Per-object color, position, scale, and orientation

Supported Primitives & Fractals

• Sphere

• Cube

• Torus

• Hexagonal prism

• Cone

• Octahedron

• Mandelbulb

• Menger sponge

• Sierpinski tetrahedron

Camera

• Free-fly camera

• Yaw / pitch mouse control

• Adjustable movement speed and mouse sensitivity

• Cursor lock / unlock

User Interface (ImGui)

• Real-time FPS counter

• Basic system information

• Enable / disable individual UI menus (F1–F4)

• Player movement and sensitivity settings

• Procedural random world generation with parameters

• Save and load worlds

Controls

Keyboard

• W / A / S / D — Move forward / left / backward / right

• Q / E — Move down / up

• Alt — Lock / unlock mouse cursor

• F1–F4 — Toggle individual ImGui menus

Mouse

• Mouse movement — Camera yaw / pitch

Technical Details

Technology Stack

• Language: C#

• Developed with .NET 10, but compatible with .NET 8 with minor code changes

• Graphics API: OpenGL

Minimum required: OpenGL 4.3 Core

Libraries:

• Silk.NET (Core, DXDI, GLFW, Input, OpenGL, OpenGL ImGui integration, Windowing, Maths)

• Dear ImGui

• System.Management(only for windows)

Rendering Architecture

Rendering is executed entirely in the fragment shader

• No compute shaders are used

• Scene data is uploaded via Shader Storage Buffer Objects (SSBOs)

• Objects are stored in a flat array (no hierarchy)

• BVH (Bounding Volume Hierarchy) is built on the CPU and transferred to the GPU to reduce raymarching steps

Shader Interface

The fragment shader receives, among others:

• Camera vectors (resolution, camera position, camera front / up / right )

• Global directional light vector

• Object buffer (SDF objects)

• BVH node buffer

Shaders are stored as external .glsl text files. There is no hot-reload; shader changes require restarting the application.

Serialization

World data is stored as JSON flat array of objects with properties:

• type

• position

• size

• Euler rotation

• color

Player data (camera position, orientation, settings) is saved separately and automatically

Performance Notes

Test system:

• CPU: Ryzen 7 7700X

• GPU: RTX 5070

• OS: Windows 11

Approximate performance:

10,000 objects, ~40 FPS at 1920×1080

No upscaling or temporal techniques used

Performance depends heavily on scene complexity and raymarching depth.

Build & Run

Supported Platforms

• Windows

• Linux

• macOS

Releases

Two binaries are provided:

• Cross-platform .NET build (all CPUs / all OSes)

• Windows x64 static build (precompiled)

Requirements

• GPU with OpenGL 4.3 Core support or higher

• Proper graphics drivers installed

• .NET runtime (for non-static builds)

Project Status

• Educational and experimental

• Considered a final version

• No guaranteed future updates

Architecture is intentionally simple and non-ideal

Intended as a learning resource rather than a reusable engine

License

This project is licensed under the GNU GPL-3.0.