资源描述：
《Microfacet Models for Refraction through Rough Surfaces》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。
1、EurographicsSymposiumonRendering(2007)JanKautzandSumantaPattanaik(Editors)MicrofacetModelsforRefractionthroughRoughSurfacesBruceWalter1†StephenR.Marschner1HongsongLi1,2KennethE.Torrance11ProgramofComputerGraphics,CornellUniversity2BeijingInstituteofTechnologyAbstractMicrofacetm
2、odelshaveprovenverysuccessfulformodelinglightreflectionfromroughsurfaces.Inthispaperwereviewmicrofacettheoryanddemonstratehowitcanbeextendedtosimulatetransmissionthroughroughsurfacessuchasetchedglass.Wecomparetheresultingtransmissionmodeltomeasureddatafromseveralrealsurfacesandd
3、iscussappropriatechoicesforthemicrofacetdistributionandshadowing-maskingfunctions.Sincerenderingtransmissionthroughmediarequirestrackinglightthatcrossesatleasttwointerfaces,goodimportancesamplingisapracticalnecessity.Therefore,wealsodescribeefficientschemesforsamplingthemicrofac
4、etmodelsandthecorrespondingprobabilitydensityfunctions.CategoriesandSubjectDescriptors(accordingtoACMCCS):I.3.7[Three-DimensionalGraphicsandRealism]:Keywords:Refraction,MicrofacetBTDF,Cook-TorranceModel,GlobalIllumination,MonteCarloSampling1.Introductiontooff-specularpeaksinrou
5、ghreflection),andthemicrofacetmodelsareabletosuccessfullypredictsucheffects.WealsoTransmissionintoorthroughrefractivemediaisanimpor-introduceanewmicrofacetdistribution,whichwecallGGX,tantcomponentintheappearanceofmanymaterials,includ-thatprovidesaclosermatchforsomeofoursurfacest
6、hantheingbothlargelytransparentmedia,suchasglassorwater,standardBeckmanndistributionfunction.andtranslucentmedia,suchasskinormarble.Whentheboundaryofamediumissmooth,thentransmissioniseasilyNextwewilldiscussrelatedwork,andthenreviewgen-modeledusingSnell’slawofrefraction.However,
7、whentheboundaryisrough,thereisalackofphysicallybasedandverifiedmodelsforuseincomputergraphics.Inthispaperwefirstreviewmicrofacettheoryandshowhow,usingageneralizationofthehalfvector,itcanbeusedtomodelbothreflectionandrefractionatroughboundariesbetweenmedia.Thisprovidesacompleteanal
8、yticBSDFmodelthatcanbeusedtosimulateroughtransmissivem
