Ray Tracing Renderer

Overview

Basic ray tracer implemented in Python as part of a Computer Graphics assignment. The ray tracer simulates light interactions by casting rays from a virtual camera into a 3D scene, determining intersections with objects, and calculating pixel colors based on materials and lighting.

Teaser

Features

• Ray-Object Intersections: Supports spheres, planes, and cubes.
• Material Properties: Implements diffuse, specular, reflective, and transparent surfaces using the Phong shading model.
• Lighting and Shadows: Uses point lights with soft shadows for realistic shading.
• Recursive Ray Tracing: Handles reflection and refraction for enhanced realism.
• Custom Scene Files: Parses scene descriptions from simple text files.

Installation & Usage

Requirements

Ensure Python 3.x is installed along with the required dependencies:

pip install numpy pillow

Running the Ray Tracer

Execute the ray tracer with a scene file:

python raytracer.py scenes/sample_scene.txt output.png --width 500 --height 500

• sample_scene.txt: Scene file defining objects, lights, and camera.
• output.png: Output image file.
• --width, --height: Optional parameters for image resolution (default: 500x500).

Scene File Format

Scenes are described using a simple text format. Example:

cam 0 0 0  0 0 -1  0 1 0  1.5 2
set 0 0 0  5 10
mtl 1 0 0  1 1 1  0.5 0.5 0.5  50 0
sph 0 0 -5 1 1
lgt 2 2 -3  1 1 1  1 1 0.5

• Defines camera, background color, materials, spheres, and lights.
• Uses simple numerical parameters for object properties.

Implementation Details

1. Ray Generation: Computes primary rays from the camera through each pixel.
2. Intersection Tests: Determines nearest surface intersections.
3. Shading Computation:
   • Diffuse and specular reflection using the Phong model.
   • Soft shadows using multiple shadow rays.
4. Recursive Reflection & Transparency: Handles mirror-like and glass-like materials.
5. Image Output: Saves the rendered scene using PIL (Pillow).