Dot-Product Reparameterizations of Tabular Isotropic BSDFs As BRDFs become more important for real-time rendering, efficient sampling of scattering functions becomes more important. This work introduces a new, simple parameterization for isotropic BRDFs and BSDFs that maintains cache-friendly, natural storage, scaling to arbitrary precision, and noninterference with importance sampling or other data-level operations such as using data generated from analytic models or from arbitrary BRDF data. Most importantly, this parameterization is far more efficient to sample than the commonly-used Equal- Angle and Half-Vector parameterizations. Additionally, the parameterization is natively adaptable to different classes of BSDF. We derive our approach from first principles, experimentally find high-quality parameters for a broad class of BSDFs, demonstrate how the approach may be refined, and establish favorable comparisons of our parameterization to existing methods by metrics of both speed and accuracy. Further optimizations and improvements are suggested.