Interactive 3D DNA helix visualizer

C++17 · OpenGL 3.3 · procedural geometry · post-processing

Overview

DNA Visualizer is a computer-graphics coursework project that renders a double-stranded DNA helix in real time. The codebase is split into small modules (core, dna, renderer, ui) and uses modern OpenGL: Phong shading, off-screen rendering via an FBO, and a post-processing stack.

Highlights

• Procedural helix — nucleotide spheres, backbone tubes, base-pair bridges
• Per-base coloring (A / T / G / C) with a Watson–Crick complementary strand
• Arcball camera and ImGui panels for scene control
• MutationEngine — point substitutions with on-screen highlight and history log
• Post-processing — Sobel edge detection, FXAA, vignette

Documentation

Detailed guides live in docs/:

Document	Topics
Overview	Index and quick reference
Architecture	Modules, main loop, data flow
Rendering Pipeline	FBO, Phong shaders, post-process
DNA Model	Sequences, helix params, mutations
Module Reference	Public classes and APIs
Build & Development	Dependencies, conventions, extending

Tech stack

Layer	Libraries
Window & input	GLFW
OpenGL loader	GLAD
Math	GLM
UI	Dear ImGui
Images	STB

Dependencies are fetched automatically via CMake FetchContent on first configure.

Getting started

Prerequisites

• CMake 3.20+
• C++17 compiler (MSVC 2019+, GCC 9+, Clang 10+)
• GPU with OpenGL 3.3 Core support
• Internet access on first configure

Build

Windows

cmake -S . -B build
cmake --build build --config Debug

Linux / macOS

cmake -S . -B build
cmake --build build

Release: add --config Release on Windows, or -DCMAKE_BUILD_TYPE=Release on Unix.

Run

Start the executable from the repository root — asset paths are relative to the working directory:

# Windows
.\build\Debug\dna_visualizer.exe

# Linux / macOS
./build/dna_visualizer

Controls

Input	Action
Left mouse + drag	Orbit camera around the helix
Mouse wheel	Zoom in / out
Esc	Quit
ImGui panels	Sequence, mutations, lighting, animation, post-processing

ImGui panels

Panel	Purpose
DNA Sequence	View coding strand, regenerate helix, point mutations
Render Settings	Animation, Phong lighting, filters, mutation log
Stats	FPS and frame time

Rendering pipeline

┌─────────────┐     ┌──────────────┐     ┌──────────────┐     ┌─────────┐
│  3D scene   │ ──► │  Framebuffer │ ──► │ Post-process │ ──► │  ImGui  │ ──► Display
│ Phong + tex │     │ color + depth│     │ Sobel/FXAA/  │     │ overlay │
└─────────────┘     └──────────────┘     │   vignette   │     └─────────┘
                                          └──────────────┘

1. Scene pass — helix meshes with Phong shading and a diffuse texture.
2. Off-screen buffer — color and depth stored in an FBO.
3. Post-process — fullscreen quad; Sobel or FXAA, then optional vignette.
4. UI — ImGui drawn on top of the final image.

See Rendering Pipeline for shader and uniform details.

Nucleotide colors

Base	Color	Complement
A	Red	T
T	Blue	A
G	Green	C
C	Yellow	G

Strand A shows the coding sequence; strand B is built from its Watson–Crick complement.

Post-processing

Effect	Description
Sobel	Edge map from scene luminance (replaces color)
FXAA	Fast approximate anti-aliasing (off while Sobel is active)
Vignette	Darkens corners; strength adjustable in UI

Project structure

dna-visualizer/
├── assets/
│   ├── shaders/          # Phong, post-process, fullscreen quad
│   └── textures/
├── docs/                 # Architecture, rendering, DNA model, API reference
├── include/
│   ├── core/             # Application, Window, InputManager, Timer
│   ├── dna/              # DNASequence, HelixGeometry, MutationEngine
│   ├── renderer/         # Shader, Mesh, Camera, Texture, Framebuffer
│   └── ui/               # UILayer, UIState
├── src/
├── CMakeLists.txt
└── README.md