Publicado em: 16/07/2012

Dissertação de Mestrado em Processamento Gráfico

UNIVERSIDADE FEDERAL DO RIO GRANDE DO SUL
INSTITUTO DE INFORMÁTICA
PROGRAMA DE POS-GRADUAÇÃO EM COMPUTAÇÃO
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DEFESA DE DISSERTAÇÃO DE MESTRADO

Aluna: Bárbara Bellaver Gonçalves
Orientador: Prof. Dr. Manuel Menezes de Oliveira Neto

Título: A Quantum Physics Approach for Simulating Agate Colors
Linha de Pesquisa: Processamento Gráfico

Data: 23/07/2012
Hora: 10h
Local: Auditório Inferior. Prédio 43413(67) – Instituto de Informática

Banca Examinadora:
Prof. Dr. Horacio Enrique Fortunato (UFRGS)
Prof. Dr. Marcelo Walter (UFRGS)
Prof. Dr. Vitor Paulo Pereira (Inst. de Geociências – UFRGS)

Presidente da Banca: Prof. Dr. Manuel Menezes de Oliveira Neto

Abstract:
Color simulation is the essence of realistic image synthesis. In the case of minerals, the presence of a given impurity, or a variation of its concentration, can cause some materials to experience dramatic changes in color. For instance, while pure quartz is transparent, amethyst is a violet type of quartz, whose color is determined by the presence of traces of iron. The amount of iron defines the perceived hue. The color presented by a mineral can be determined based on its absorption spectrum. However, defining all possible variations is impractical and, therefore, such information is available only for a subset of the existing minerals. This thesis presents an approach for simulating the colors of existent agates, as well as for predicting the colors for (non-existent) synthetic ones. The approach is based on the fundamentals of quantum theory, and starts with the description of the silica molecule one wants to simulate. One can add different amounts of impurities, and alter the number of atoms included in the simulation. The obtained result is the absorption spectra of the mineral, which can then be used for determining the color of the agate with the desired composition. Although a detailed simulation of the entire process is extremely computationally-expensive, the thesis presents some results that corroborate the correctness of the proposed solution. It also introduces a standalone technique for defining agate volumes based on 2D images of agates.

Keywords: Agates, Color Computation, Quantum Physics, Minerals.