This project has been created as part of the 42 curriculum by amtan, yunguo.

42 is a global tuition-free programming school network built around peer learning and project-based education. This project was completed at 42 Singapore, the Singapore campus of the 42 Network.

miniRT

Description

miniRT is a 42 core curriculum project in which students build a small ray tracer in C.

The program reads a .rt scene file, parses the scene data, casts camera rays into the scene, finds the closest object intersections, computes lighting and shadows, and displays the rendered image in a MiniLibX/X11 window.

The mandatory part supports:

• Ambient light, camera, and light

• Spheres, planes, and cylinders

• Translation, rotation, and object resizing where applicable

• Ambient and diffuse lighting

• Hard shadows

• Clean error handling for invalid .rt files

• Clean exit with ESC or the window close button

The bonus part adds:

• Specular highlights

• Checkerboard pattern

• Colored and multiple lights

• Ellipsoid as an additional second-degree object

• Sine and Perlin-style bump mapping

Instructions

This project is intended to run on Linux with X11.

Required packages include:

sudo apt-get install gcc make xorg libxext-dev libbsd-dev

The repository includes shared copies of:

libft/
minilibx-linux/

MiniLibX is used for window creation and image display.

Build mandatory

make

or:

make all

This creates:

./miniRT

Run with:

./miniRT tests/parser/valid_minimal.rt

Build bonus

make bonus

This creates:

./miniRT_bonus

Run with:

./miniRT_bonus tests/scenes_bonus_defense/08_all_bonus_combined.rt

Clean

make clean
make fclean
make re

make clean removes object files. make fclean removes object files and executables. make re rebuilds the mandatory executable from scratch.

Scene Format

A valid scene must contain:

A   ambient light
C   camera
L   light

Basic example:

A 0.20 255,255,255
C 0,0,-60 0,0,1 70
L -30,30,-25 0.75 255,255,255
sp 0,0,0 20 180,180,255

Mandatory object identifiers:

sp    sphere
pl    plane
cy    cylinder

Bonus object and optional tokens:

el       ellipsoid
is_chkr  enable checkerboard
no_chkr  disable checkerboard
sine     sine bump map
perlin   Perlin-style bump map
empty    no bump map

Bonus examples:

sp 0,0,0 20 180,180,255 is_chkr sine
el 0,0,0 24,14,14 180,180,255 no_chkr perlin

Useful Test Scenes

Mandatory:

./miniRT tests/evalsheet_mandatory/basic_sphere_origin.rt
./miniRT tests/evalsheet_mandatory/complex_shadows.rt

Bonus:

./miniRT_bonus tests/scenes_bonus_defense/01_specular_phong.rt
./miniRT_bonus tests/scenes_bonus_defense/02_checkerboard.rt
./miniRT_bonus tests/scenes_bonus_defense/03_colored_multi_lights.rt
./miniRT_bonus tests/scenes_bonus_defense/04_ellipsoid_quadric.rt
./miniRT_bonus tests/scenes_bonus_defense/05_sine_bump.rt
./miniRT_bonus tests/scenes_bonus_defense/06_perlin_bump.rt
./miniRT_bonus tests/scenes_bonus_defense/08_all_bonus_combined.rt

Invalid-scene examples:

./miniRT_bonus tests/scenes_bonus_defense/09_bad_missing_light.rt
./miniRT_bonus tests/scenes_bonus_defense/10_bad_ellipsoid_zero.rt

Invalid scenes should print Error with an explanatory message and exit without opening a render window.

Resources

References used while working on this project:

• 42 miniRT subject

• MiniLibX Linux source

• Scratchapixel ray tracing lessons

• Ray Tracing in One Weekend by Peter Shirley

• The Ray Tracer Challenge by Jamis Buck

• Phong reflection model overview

• Perlin noise overview

• Bump mapping overview

• Xlib / X11 documentation

• 42 Norm

MiniLibX Linux is a simple X11 programming API for 42 students and is built locally with make or ./configure. Scratchapixel was used as a reference for the basic ray tracing pipeline: primary rays, object intersections, closest-hit selection, and shading concepts.

AI Usage

AI assistance was used as a learning, testing, and review tool.

It was used for:

• Explaining ray tracing concepts

• Planning mandatory and bonus test scenes

• Drafting evalsheet-style test checklists

• Investigating parser, lighting, bump mapping, and bonus-object bugs

• Suggesting small patch ideas

• Assisting with Norm-focused refactoring after behavior was tested

• Drafting README text

All final code, compilation, rendering tests, parser tests, Valgrind checks, Norminette checks, and project decisions were manually verified by the authors.