CS 6620 - Fall 2017 - Ray Tracing for Graphics

Project 14 - 8 Teapots

Kevin Parker

This scene contains almost zero direct lighting and is made entirely of teapots. The room itself is a teapot, there is a teapot in the middle, and the images on the walls are the base of teapots. Just like a real teapot, light is poured in through the spout.

There are a total of 8 teapots in this scene, of 4 different types. One is the teapot the scene is housed in. Another is visible in the middle-bottom of the screen. 5 are the geometry for the textured pictures shown. And the last one is on top of the light to help reduce leakage.

I am not as pleased with this scene as I hoped I would be, although I am quite pleased with the software I made it with. I ended up writing several scripts to manipulate *.obj files to manipulate texture coordinates, normals, faces, and so forth. I also wrote the software I used to composite my final image, partially because I was curious to give it a try. And of course I made hundreds of changes to the actual ray tracer to make it as correct as possible.

I thought it would be an interesting idea to create a scene purely out of teapots, but it ended up being somewhat of a hassle and did not create a very exciting image. It does give a technical test to the renderer, giving it a scene where the light is occluded and everything must be globally illuminated, but it just gives the scene an "ambient lighting" feel rather than a "flow of light"-type idea. This also caused render times to be incredibly high and very grainy (The above image represents many hours of render time). Finally, the "paintings" on the wall, which are texture-mapped teapots with the top 90% sticking out of the wall, didn't look very interesting. If I had another week to dedicate to making a nice scene, I would consider creating a scene involving volume rendering or other more advanced techniques, but after having 6 final projects/finals this semester, the above is about how much creativity I had left.


Like several others of the students, I spent a significant amount of time this week fixing bugs for the renderer. I have put those under the previous project, as I was sampling pieces of it using that scene. Once I had the renderer mostly the way I wanted it, here is some of my progress in creating and rendering the scene above.

An initial try

More photons

Including textured teapot bottoms as pictures (had to letterbox images to keep aspect ratio)

Increased the brightness of the letterboxing

Something was occluding the light (which was at the top of the spout)

Increased brightness

Moved spout to avoid the occlusion

Turned teapot into glass

Fixed some lighting issues (notice the specular reflection on the teapot)

A bug was causing the renderer to not work correctly on Linux (producing this result)

A grainy render of the final scene

Machine Specs

MacBook Pro (15-inch, 2016)

2.7 GHz quad-core Intel Core i7 Skylake (6820HQ)

16 GB 2133 MHz LPDDR3 RAM