Assignment 1
Installing pbrt
I built pbrt using VS2005 on XP. My first error came from spaces in the pbrt path. Another error came from incorrectly altering the Solution's path to OpenEXR. I was convinced at one point that the calls to Bison and Flex were missing a space, and that adding a space had fixed my build problems, but this turned out to be pure superstition.
Rendering
I quickly grew tired of waiting so long for each 300x300 render to see the effects of my tiny changes. I decided to mock up my lighting in Maya, where I could position lights in real-time and get accurate renders very quickly. I used a sphere as a stand-in for the head. I continued using Maya to mock up my lighting for each of the four renders before copying the positions and rotations of each object into the pbrt file. The match was pretty accurate and from there I would manually tweak the pbrt file until I was happy. I noticed very quickly that only one of the cpu-cores in my computer would work on a render and took to working on two files at once, tweaking one while the other rendered or rendering both images at once. On the fourth image I finally realized the value of taking down the image resolution and samples per pixel.
Experimentation
- I did not realize until moments ago that we were supposed to try and match the sample images exactly. I used the the same lighting configurations but tweaked the look more to my personal preference than to matching the sample images. Generally, my images are more softly lit.
- I was baffled by the coordinate system. The book declares pbrt to be left-handed yet any change I made seemed consistent with a right-handed system. I suspect that my changes were in camera-space rather than world-space. Further experiments are needed.
- I attempted to install a pbrt plug-in for Maya but it did not immediately work. The plug-in was built for a later version than I had on my PC. I will put more time into getting this working if it seems valuable for future projects.