I decided to render a larger model. So i took the happy buddah model from stanford repository. It contains 543652 points and 1087716 triangles. Rendering a 256×256 image took approximatively 2 hours. I really need surface partitioning.

The white dots on the picture represent the ray where a floating point error occured. As the mesh has really small triangles and low coordinates points, i had to replace the zero divider test using boundaries by the standard not equal to zero test. I really hate this floating point issues…