“Bringing an Accurate Fresnel to Real-Time Rendering: a Preintegrable Decomposition” by Belcour, Bati and Barla

  • ©Laurent Belcour, Mégane Bati, and Pascal Barla



Entry Number: 76


    Bringing an Accurate Fresnel to Real-Time Rendering: a Preintegrable Decomposition



    We introduce a new approximate Fresnel reflectance model that enables the accurate reproduction of ground-truth reflectance in real-time rendering engines. Our method is based on an empirical decomposition of the space of possible Fresnel curves. It is compatible with the preintegration of image-based lighting and area lights used in real-time engines. Our work permits to use a reflectance parametrization [Gulbrandsen 2014] that was previously restricted to offline rendering.


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©Laurent Belcour, Mégane Bati, and Pascal Barla ©Laurent Belcour, Mégane Bati, and Pascal Barla


    The authors thank Thomas Deliot for implementing the method in the Unity engine and Kenneth Vanhoey, Jonathan Dupuy and Eric Heitz for proof-reading.


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