This project has been created as part of the 42 curriculum by sgadinga, zsalih

miniRT — A Raytracer in C

Description

miniRT is a ray tracing engine built from scratch in C as part of the 42 school curriculum. The goal is to render 3D scenes described in .rt scene files by simulating the physical behavior of light rays — tracing each pixel's ray from the camera into the scene, computing intersections with geometric objects, and applying lighting models to produce a realistic image.

The engine supports a full set of geometric primitives, advanced lighting with the complete Phong reflection model, and several bonus features including cone rendering, checkerboard patterns, multi-spot colored lights, and bump map texture support.

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Instructions

Requirements

• Linux OS
• cc and make
• X11 development libraries (required by MiniLibX)

Install the required dependencies:

sudo apt update
sudo apt install build-essential libx11-dev libxext-dev zlib1g-dev

Required for MiniLibX linking: -lXext -lX11 -lm -lz

Compilation

Clone the repository and compile with:

make

To clean object files:

make clean

To fully clean (including the binary):

make fclean

Execution

./minirt scene/<scene_file>.rt

Example:

./minirt scene/15_earth.rt

Scene files describe the camera, lights, and objects in the scene. They must follow the .rt format defined by the project specification (see Scene Format documentation)

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Features

Mandatory

• Support for geometric primitives: sphere, plane, and cylinder
• Accurate ray–object intersections, including correct handling of object interiors
• Object properties:
  • Sphere: adjustable diameter
  • Cylinder: adjustable diameter and height
• Full geometric transformations:
  • Translation and rotation for objects, lights, and camera
  • (excluding rotation for spheres and lights, as per subject constraints)
• Lighting system:
  • Ambient lighting (ensuring no complete darkness)
  • Diffuse lighting
  • Hard shadows
  • Configurable light intensity (brightness)
• Scene rendering from .rt files following the project specification

Bonus

• Advanced lighting
  • Full Phong reflection model (ambient + diffuse + specular)
  • Support for multiple colored light sources
• Texturing
  • Checkerboard patterns (procedural textures)
  • Bump map textures for surface detail via normal perturbation
• Additional geometry
  • Cone support (second-degree primitive beyond mandatory objects)

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Internal Libraries

• libtensr — custom math and geometry library
  Provides vector operations, math utilities, and core structures used in the ray tracing engine.

• libft - foundational utility library
  Provides standard C functions and basic utilities used across the project.

Included as part of this repository.

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Documentation

For a deeper understanding of the project architecture and implementation details:

• Architecture Overview
• Rendering Pipeline
• Scene File Format
• Threading Model
• User Interactive Settings

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Resources

Ray Tracing & Mathematics

• Ray Tracing Gems (v1.9) — Haines et al.
  Comprehensive reference on ray tracing techniques, intersection math, and lighting models.

• Khan Academy — Linear Algebra
  Foundational reference for vectors, dot products, cross products, and matrix transformations — all essential to ray tracing.

• The Cherno — Ray Tracing Series (YouTube)
  Step-by-step ray tracing series covering the basics through practical implementation.

• Sebastian Lague — Coding Adventures: Ray Tracing (YouTube)
  Visual walkthrough of ray tracing fundamentals with clear explanations.

• LearnOpenGL — Normal Mapping
  Reference for understanding and implementing bump map / normal map textures.

• NumPy Reference
  NumPy library reference manual, which inspired the design for the libtensr library.