Real-time rendering of realistic surface diffraction with low rank factorisation

Abstract

We propose a novel approach for real-time rendering of diffraction effects in surface reflectance in arbitrary environments. Such renderings are usually extremely expensive as they require the computation of a convolution at real-time framerates. In the case of diffraction, the diffraction lobes usually have high frequency details that can only be captured with high resolution convolution kernels which make calculations even more expensive. Our method uses a low rank factorisation of the diffraction lookup table to approximate a 2D convolution kernel by two simpler low rank kernels which allow the computation of the convolution at real-time framerates using two rendering passes. We show realistic renderings in arbitrary environments and achieve a performance from 50 to 100 FPS making possible to use such a technique in real-time applications such as video games and VR.

Acquiring spatially varying appearance of printed holographic surfaces

“…They also demonstrate viewdependent rendering under complex environmental lighting using pre-filtering. In subsequent work, Toisoul and Ghosh [2017b] employ low rank factorization of acquired 2-D diffraction patterns for efficient real-time rendering. We employ their rendering method in this work for rendering spatially varying 1-D sinusoidal gratings under complex environmental illumination.…”

“…We present environmental rendering of various acquired holographic papers in Fig. 21 using the rendering method of [Toisoul and Ghosh 2017b]. Note that for performance reasons, we do not take into account the Gaussian coherence window in the environmental rendering and only use a delta Dirac response instead.…”