The scene symbolizes a rite of passage that every CS student at Habib University have been through, the infamous Tower of Hanoi. What struck us about the problem is how remarkably simple was it to code a solution based on recursion. I might still be able to remember the three lines of pseudocode which were implemented in the Programming Fundamentals course.
After visualizing the concept, the scene was modelled in Blender consisting of Blender primitives such as tori and Suzanne (the monkey) while other objects were hand-sculpted from cylinders and circles. There are 9.7 million triangles in the scene with many of them being used to better approximate the curved surfaces, including the tori.
We implemented the following features in our ray tracer.
We implemented four different types of light, Ambient Light, Point Light, Directional Light and Spotlight.
We implemented phong, matte and reflective materials. For perfectly specular materials, the diffuse component is zero, while for perfectly diffuse or matte material, the specular component is zero. A combination of specular and diffuse components produces phong material.
We used the Bi-Directional Reflectance Distribution Function(BRDF's) to compute how light is reflected at surfaces. We implemented Lambertian, Glossy Specular and Perfect Specular.
All our implemented light sources support shadows through the concept of secondary ray generation. Shadows can be switched off/on in build functions.
We implemented Oct-Tree as our acceleration structure.
Both parallel and perspective viewing is supported in our raytracer.
Our raytracer supports planes, triangles, spheres and boxes as the basic geometric primitives.
For smoothing out edges, we implemented regular and random samplers in our raytracer. Multiple rays are shot per pixel producing a much nicer interpolation in the colors assigned to each pixel. Regular sampling, involves a fixed number of rays for each pixel in our case, 16.
A list of implemented bonus functionalities is given below.
Our ray tracer supports loading scenes as .obj file. A mesh or any scene consisting of multiple meshes can simply be first exported to .obj format through a 3D software and can then simply be loaded into our ray tracer.
We used Blender for modelling and exporting our concept scene.Any scene that can be viewed in Blender can be directly loaded as an .obj in our raytracer. the scene was rotated such that the camera is looking into the positive y direction, this is the view that was rendered in our final raytracer.
The following tables compare the render times of our ray tracer with and without acceleration grids. The rendering was done on a hardware with following configurations:
| Time With Oct Tree | Time Without Oct Tree | Number of Primitives (triangles) | Resolutions |
|---|---|---|---|
| Time With Oct Tree | Time Without Oct Tree | Number of Primitives (triangles) | Resolutions |
| 6.102 | 3.618 | 10 | 1920 x 1920 |
| 14.896 | 16.542 | 100 | 1920 x 1920 |
| 49.21 | 173.202 | 1000 | 1920 x 1920 |
| 550.12 | 2200+ | 1000 | 1920 x 1920 |
| 0.349 | 0.288 | 10 | 400 x 400 |
| 0.806 | 1.013 | 100 | 400 x 400 |
| 3.855 | 7.895 | 1000 | 400 x 400 |
| 8.042 | 78.332 | 10000 | 400 x 400 |
This scene consists of a box, triangle and sphere of matte material with different lights.
This scene consists of a box, triangle and sphere of phong material with different lights.
This scene This scene was already provided, modified it; now consists of a sphere and plane with different lights.
This scene was already provided, we modified it to take care of anti-aliasing.
This is the scene with reflective sphere and whitted tracer.
This scene was already provided, but we modified it with reflective materials and whitted tracer.
This scene renders a monkey with primitives as triangles.
