Lightcuts implementation

During the past week I completed my lightcuts implementation. Concretely this means I added cosine weighted point lights and directional lights (clustering & bounds), a bound for the Blinn microfacet distribution and support for global illumination using the Instant Global Illumination algorithm as implemented in the igi plugin for pbrt.
All of the following pictures where rendered using this updated implementation on my Core2 Duo T7100 system using 4 samples per pixel. The first picture is once again the cornell box but now using 1024 cosine weighted lights instead of omni directional lights with a maximum relative error of 2%. The total render time for this picture was 227s and the average cut size was 104.



The second picture shows a modified cornell box with glossy objects and global illumination. The total number of light sources used was 760000 which were mostly for the indirect light. The required time was 632s and the average cut size 206.



The final picture shows a glossy dragon statue lit by the grace environment map. This environment map was approximated by 256000 directional lights distributed evenly over the entire sphere of directions. The total render time was 1557s and the average cut size 218.