Photorealistic visualization of fluorescence materials with dual surface scattering

摘要

The article is devoted to simulation of photorealistic images of materials with fluorescent properties. Usuallymeasurements and simulations of scattering surfaces of objects with fluorescent properties is complex and expensivetask. The source of problem is dependence of spectral characteristics of output scattered light from spectralcharacteristics of input light. There are two methods to simulate complex light scattering of similar materials. The firstmethod is based on measurements of bi-directional scattering functions (BSDF) describing surface scattering. Thesecond approach is based on total reconstruction of parameters of VS medium. Simulation of real ray propagation insideof fluorescent volume scattering medium is complex and time consumed task because of huge number of ray interactionswith fluorescent scattering agents especially if their concentration is significant. We propose alternative method tosimulate fluorescent materials. The approach does not require complex and expensive measurements of“fluorescent“ BSDF. A hybrid method to measure and simulate fluorescence objects is proposed. The specular part ofscattering can be simulated with BSDF based on measurements of usual material without fluorescence effect. Note onlydirections close to specular direction are used from this BSDF. Diffuse part of scattering is simulated with standardspectrograms well-known in many description of fluorescence: fluorescence efficiency and fluorescent emission. Thisseparation of fluorescent and “usual” part of scattering allows effective use of different techniques for visualization fromrather simple Backward Ray Tracing to more complex approaches of ray visualization which use combined forward andbackward techniques of ray tracing.