Accurate Diffuse Lighting From Spherical Gaussian Lights

Abstract

1 Accuracy of Our Approximation 1.1 Clamped Cosine Fig. 1 shows the error of our spherical Gaussian (SG) approximation for clamped cosine. Our approximation balances the approximation error and numerical error to reduce the sum of them. Even without using Kahan’s precise computation [Kahan(2004)] for Eq. 3 in the main document, the maximum numerical error is still almost the same as the maximum approximation error. Difference