New tracer

Based on the fact that I got stuck in implementing the GPU KD-tree paper, I decided to turn to something else.

I've been reading things related to HDR and found it's pretty interesting, and I'm not satisfied with my previous two tracers. So I want to re-write my tracer.

The plan could be like:

Step 1: set up the all the openGL stuff. Rendering everything on to a frame buffer and display the frame buffer with time. Setting up the basic scene is necessary for this step, including camera and the most simple ray trace function(could be just returning a color based on the pixel coordinates).

Step 2: enrich the scene. Setting up objects class and material class. Implement basic ray trace algorithm, which is easy. The material class should be compatible with the HDR, cause that's what I'm trying to focus on for this project. The result of this step is ray-traced image of a simple scene(could be a cornell box with a single sphere).

Step 3: build a CPU kd-tree for complicated objects like stanford bunny or armadillo. Change ray trace with monte carlo path trace. My implementation of material class have to be changed to be better modulized to used BRDF. The result of this one should be a nice rendered image which could function as reference image. Yet the process must be really slow.

Step 4: try implementing the GPU kd-tree paper again and ship everything onto GPU, or try implement photon mapping in the tracer. Haven't thought about that far yet.

Hopefully this project could keep me busy for a while. I'll keep the progress updated.