Quad‐Based Fourier Transform for Efficient Diffraction Synthesis

Abstract

Far‐field diffraction can be evaluated using the Discrete Fourier Transform (DFT) in image space but it is costly due to its dense sampling. We propose a technique based on a closed‐form solution of the continuous Fourier transform for simple vector primitives (quads) and propose a hierarchical and progressive evaluation to achieve real‐time performance. Our method is able to simulate diffraction effects in optical systems and can handle varying visibility due to dynamic light sources. Furthermore, it seamlessly extends to near‐field diffraction. We show the benefit of our solution in various applications, including realistic real‐time glare and bloom rendering.

Interactive Black-Hole Visualization

“…A texture with a diffraction pattern is used as a convolution filter on the matrix of pixel values, where only pixels that have a high enough brightness are affected. For our experiment we chose the 100 × 100 texture from Scandolo et al [27] (Fig. 13).…”

“…Star effects: default stars, gaussian star spread, star trails, diffraction and the image used as convolution kernel[27].…”