BSDF ÖLÇÜMLEMELERİNİN VE SUNUMLARININ İNCELENMESİ

Işık yansıması ve iletiminin doğru bir şekilde ölçümlenip sunulması malzemelerin yüksek doğrulukta görsel simülasyonu için çok önemlidir. Bu makalede, literatürdeki en son İki Yönlü Saçılım Dağılım Fonksiyonu (BSDF) ölçümlemeleri ve modelleri incelenmektedir. Literatürdeki en son BSDF modellerinin camlardan metallere, izotropikden anizotropiğe ve ışığı yeniden yönlendiren filmlere kadar bir çok yüzey tipi için genel bir çözüm önermedikleri gösterilmiştir. Bunun dışında, özellikle normal geliş yönü ve süpürme açıları gibi spesifik ölçümleme açılarında doğru ve yoğun BSDF ölçümlemesinin kolay olmadığı gösterilmiştir. Bu makalede, etkin BSDF ölçümlemesi ve sunumu için genel bir çözüm bulma problemine yönelinmiştir. Ayrıca, mevcut BSDF sunumlarının etkin olarak kullanımına müsaade etmeyen ana konular belirtilmiştir. Son olarak, BSDF literatüründe incelenmesi gereken açık araştırma konuları önerilmiştir

Anahtar Kelimeler:

Görünüm modeli, Görünüm ölçümlemesi, İki yönlü saçılım dağılım fonksiyonu, BSDF, Görüntüleme

A SURVEY OF BSDF MEASUREMENTS AND REPRESENTATIONS

Measuring and representing light reflection and transmission accurately are core to high fidelity visual simulation of materials. In this paper, we analyze state-of-the-art Bidirectional measurements and models. We show that the most of the state-ofthe-art BSDF models do not suggest a general solution for any surface class, from glasses to metals, isotropic to anisotropic materials, and daylight redirecting films. Furthermore, it’s shown that an accurate and dense BSDF acquisition is not a trivial task at especially some specific measurement angles, such as normal incidence and grazing angles. In this paper, we address the problem of finding a general solution for efficient BSDF measurement and representation. We also outline the main issues that do not allow the effective use of current BSDF representations. Finally, we suggest open research issues that need to be investigated in BSDF literature

Keywords:

Appearance model, Appearance capture, Bidirectional scattering distribution function, BSDF, Rendering,

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