Wang, LeiIwasaki, KeiCeylan, DuyguLi, Tzu-Mao2025-05-092025-05-092025978-3-03868-268-41017-4656https://doi.org/10.2312/egs.20251033https://diglib.eg.org/handle/10.2312/egs20251033Differentiable rendering requires the development of importance sampling for derivative functions with respect to the parameters. While importance sampling for Bidirectional Reflectance Distribution Function derivative has been proposed in recent years, no methods have been introduced for the derivatives of Bidirectional Curve Scattering Distribution Function (BCSDF). To bridge this gap, we propose an importance sampling method for the derivatives of the BCSDF using positivization [BXB∗24]. Our BCSDF derivative importance sampling method achieves up to 94% reduction in RMSE for eqaul-time rendering.Attribution 4.0 International LicenseCCS Concepts: Computing methodologies → RenderingComputing methodologies → Rendering10.2312/egs.202510334 pages