An inverse method for the exploration of layered material appearance

Abstract

Layered materials exhibit a wide range of appearance, due to the combined effects of absorption and scattering at and between interfaces. Yet most existing approaches let users set the physical parameters of all layers by hand, a process of trial and error. We introduce an inverse method that provides control over BRDF lobe properties of layered materials, while automatically retrieving compatible physical parameters. Our method permits to explore the space of layered material appearance: it lets users find configurations with nearly indistinguishable appearance, isolate grazing angle effects, and give control over properties such as the color, blur or haze of reflections.

SpongeCake: A Layered Microflake Surface Appearance Model

“…Being a useful forward model, SpongeCake also be helpful when used for inverse rendering, even for inverse rendering of layered materials [Bati et al 2021], since the model is analytic and has good expressive power for representation with a relatively small parameter space, and is also easily made diferentiable. For example, in Fig 20 , we manually set the parameters to match our results with those from microfacet models.…”

Extraction of Characteristics of Solid Pigments from Paint Samples

“…There is PWC (and concentration) in dry paint and in wet paint. 𝑚𝑚 𝑎𝑎𝑖𝑖𝑏𝑏𝑏𝑏𝑒𝑒𝑟𝑟 + ∑ 𝑚𝑚 𝑝𝑝𝑎𝑎𝑠𝑠𝑒𝑒𝑒𝑒 (𝑗𝑗) 𝑗𝑗 , (11) where the superscript enumerates pigments, the lowercase 𝑚𝑚 stands for the dry mass and the uppercase 𝑀𝑀 means the wet mass.…”

“…As a result, the appearance of the surface may differ from the initial one. Attempts to find an automatic solution for this ambitious task have been undertaken by various teams for more than a decade [8][9][10][11]. We also made attempts to solve the problem of determining the paint composition by its appearance [12,13].…”

“…Introducing coefficients of drying 𝑞𝑞 = 𝑚𝑚/𝑀𝑀 which are rather easy to measure, and using (11) one has…”

In‐the‐wild Material Appearance Editing using Perceptual Attributes

“…Given the large amount of dimensions that our perception involves, many works have focused on editing material appearance by estimating the known parameters of the scene (material, geometry, and illumination), thus solving an inverse rendering problem where the material is later modified [BBP21, YX16]. However, this approach faces several problems: noise in the estimation of scene parameters can yield uncanny editing results.…”