A CPU-based path tracer written in C++14, following Peter Shirley's Ray Tracing in One Weekend.
I built this to learn the fundamentals of ray tracing and physically-based rendering. It follows the first book in Peter Shirley's ray tracing series and implements the full pipeline from ray-sphere intersection all the way to a final rendered PNG with multiple materials. The random scene generator produces the classic "lots of small spheres" cover image from the book, which was a satisfying milestone to hit.
- Materials: Lambertian (diffuse), Metal (with configurable fuzz), and Dielectric (glass with Schlick reflectance approximation and refraction)
- Anti-aliasing: Multi-sample per pixel (100 samples by default)
- Gamma correction: Applied with gamma = 2.0
- Depth of field: Configurable aperture and focus distance via a thin-lens camera model
- Random scene generation: Procedurally places hundreds of small spheres with randomized materials
- PNG output: Renders directly to PNG using stb_image_write (no PPM intermediate)
- Recursive ray bouncing: Configurable max depth (50 bounces by default)
- C++14
- stb_image / stb_image_write (vendored in
res/vendors/stb_image/)
- A C++ compiler with C++14 support (e.g., clang++, g++)
- git
Clone the repo:
git clone https://github.com/mosamaasif/RT_in_a_Weekend_Ipml.git
cd RT_in_a_Weekend_IpmlFrom the project root, compile and run:
clang++ -std=c++14 -stdlib=libc++ \
-I res/utils \
-I res/vendors/stb_image \
src/main.cpp res/utils/HittableList.cpp res/utils/Sphere.cpp \
-o bin/release/main
./bin/release/mainThe rendered image will be written to output/out.png.
Note: The build command above is for macOS with clang++. For other platforms or compilers (g++, MSVC), adjust the compiler and flags accordingly. A VS Code tasks.json with debug and release configurations is also included in .vscode/.
Random scene -- hundreds of diffuse, metal, and glass spheres with depth of field:
Three spheres -- Lambertian (blue), Metal (gold), and Dielectric (glass):
