This project implements a raytracer in C++ from scratch, made without the use of any graphic libraries.
Objects (in .off format) are loaded into the scene within main.cpp and an output .png image is generated.
The raytracer is implemented using a perspective view and supports shadows, and reflections. The main focus of the program is to use an AABB Tree which spacially partitions triangle faces into a binary search tree in order to optimise ray intersection computations by quickly eliminating large subsets of triangles from the list of triangles that need to be checked for a possible intersection with the ray.
By implementing an AABB Tree, raytracer performance is massively increased compared to the brute force method.
Wereas the provided dragon.off model with nearly 1 million triangles would typically take hours to render using the brute force method raytracer, the AABB Tree version renders the model in about 15 seconds.
For comparison, the bunny.off model with about 1000 triangles takes 14 times as long to render using brute force than the 1 million triangle dragon.off with AABB Tree:
| Model | Time |
|---|---|
| bunny (brute force) | 3:30 mins |
| dragon (AABB Tree) | 15-20 secs |
Below are some sample images rendered using the AABB Tree raytracer.
Note that the scene is rendered with 7 light sources for shadows and that reflection computation has a ray bounce recursion depth of 5. Final images are rendered in 640x480 resolution.
Fig 1: The dragon.off model rendered with shadows and reflections.
Fig 2: The dragon.off model rendered shadows but no reflections.
Fig 3: The bunny.off model rendered with shadows and reflections.