# Modelling and Predictive Rendering of Materials Using Microgeometry

Bojja Venu: Modelling and Predictive Rendering of Materials Using Microgeometry

Predictive rendering is a sub-discipline of computer graphics, and it attempts to give realistic predictions of material appearance. For the predictive rendering of material appearance, we need to understand interactions between light and matter, and how human brain perceives those interactions. The appearance of a thing(like materials) depends on its shape and on how it is illuminated. Generally, we can follow the path of light from a light source(illumination) and see where it reaches an object. The light interacts with geometric features in a surface down to a very small scale. Commonly used material appearance models don’t consider light matter interactions at microscopic level.

For example, product appearance consists of different stages like design, specification and quality assessment, and optical and mechanical properties at each stage influenced by micro-geometry. Micro-geometry influences many more things like fluid flow control in materials, engineering of optical materials like lasers, LEDs, sensors, solar cells etc.

Modeling the micro-geometry of materials and appearance specification through micro-geometry during rendering are important goals of this project. In this project, I will attempt to mathematically represent all the tiny surface details that light can see. Once we know what surface details light can see, we can more easily find out interactions between light and geometry, and this will help predict how an observer or a camera will likely perceive the appearance of the surface. This is a difficult task because the scale is so small, because of that it is not possible to measure and store information about all the tiny details in a surface. It is important to model spatial variations like micro-geometry variation throughout the volume and surface of the material.

Surface details of the material can be generated using mathematical model depending on how we find out that light reaches(interacts with) it. Since the model of surface details can be modified depending on different types of processing of a material surface, this can be used to predict how a manufacturing process will affect the appearance of a product. Our research can also be used to better understand the processes an object has gone through, based on photographed appearance of objects(materials) that we find.

## PhD Project

By: Bojja Venu

Section: Visual Computing

Co-supervisor: Jakob Andreas Bærentzen

Term: 01/11/2021 → 31/10/2024

Venu Bojja
PhD student
DTU Compute