Country Kitchen

The Country Kitchen demonstrates the difficult case of highly directional environment light entering an interior scene and interacting predominantly with reflective materials, such as the glass table and the mirror. Traditional path-tracing techniques can not handle the difficult specular-diffuse-specular light transport - seen through the mirror on the ceiling - and struggle with the caustic under below the glass table. Radiance-based path-guiding methods can sample these difficult cases, with our NPG-Radiance performing the best among them at equal sample counts. Incorporating the product (NPG-Product) offers further improvements, in particular on glossy materials such as the wall behind the stove. Primary-sample-space path-sampling techniques offer little to no benefit over unidirectional path tracing with our NPS slightly outperforming PSSPS [Guo et al. 2018] with an equal number of samples.