Modelling and Simulation of Lily flowers using PDE Surfaces

This paper presents a partial differential equation (PDE)-based surface modelling and simulation framework for lily flowers. We use a PDE-based surface modelling technique to represent shape of a lily flower and PDE-based dynamic simulation to animate blossom and decay processes of lily flowers. To this aim, we first automatically construct the geometry of lily flowers from photos to obtain feature curves. Second, we apply a PDE-based surface modelling technique to generate sweeping surfaces to obtain geometric models of the flowers. Then, we use a physics-driven and data-based method and introduce the flower shapes at the initial and final positions into our proposed dynamic deformation model to generate a realistic deformation of flower blossom and decay. The results demonstrate that our proposed technique can create realistic flower models and their movements and shape changes against time efficiently with a small data size

ON AN EVOLUTIONARY DEVELOPMENTAL METHODOLOGY FOR PIN-JOINT FRAMEWORK OPTIMIZATION

M.S.M.S. Thesis. University of Hawaiʻi at Mānoa 201

Modélisation de fruits, de leur structure interne et de leurs défauts

One of the largest areas of research in computer graphics deals with natural phenomena representation. Over the years, as our understanding of nature grew, researchers started to propose new ways of simulating the various natural phenomena that we can observe in our everyday life. In this thesis, we focused on the representation of fruits. The fruit is a complex object. Depending on the desired accuracy, modeling a 3D fruit using classic 3D modeling software can become very tedious. We propose a model for generating vast varieties of fruits as well as their internal structure, thanks to the use of a single formal grammar. Each fruit that will be generated using our method will have global features that characterize its species, but it will also have local variations that are specific to it. The second part of ou work involves the representation of geometrical imperfections along the fruit. The fruit is the result of a series of physiological processes that strongly interact with each other. When one of these processes does not work the way it should, this dysfunction is materialized in the form of a shape defect. Our model introduces a simple approach, based on the use of grammars, which will allow us to apply variations on fruits in order to generate various categories of shape defects.La représentation de phénomènes naturels fait partie des domaines les plus complexes et les plus actifs de la recherche en informatique graphique. Notre compréhension de la nature s'améliorant au fil des années, les chercheurs ne cessent de proposer des nouveaux modèles, toujours plus pertinents les uns que les autres, et permettant de reproduire les différents phénomènes naturels que nous pouvons observer autour de nous, dans la vie de tous les jours. Nous nous sommes intéressés à la représentation du fruit et des différents éléments qui le caractérisent. Le fruit est un objet complexe et, en fonction de la précision requise, sa conception à l'aide de logiciels de modélisation 3D peut très vite devenir compliquée. Notre modèle permet de générer une grande variété de fruits de formes différentes ainsi que les différents éléments de leur structure interne et ce, grâce à l'utilisation d'une seule grammaire. Au sein d'une même espèce, les fruits générés seront tous différents au niveau de leur forme, tout en restant semblables. La seconde partie de nos travaux porte quant à elle sur la représentation des imperfections géométriques qui sont propres aux fruits. Les fruits sont le résultat de l'enchaînement d'un très grand nombre de processus physiologiques complexes qui interagissent fortement entre eux. Lorsque le bon fonctionnement de l'un de ces processus est compromis, cette anomalie se matérialise sur le fruit par l'apparition de défauts au niveau de sa forme. Notre modèle propose une approche simple, basée sur l'utilisation de grammaires, qui permettent d'altérer soit la forme générale d'un fruit soit des parties de sa surface

Modeling and Visualization of Multi-material Volumes

The terminology of multi-material volumes is discussed. The classification of the multi-material volumes is given from the spatial partitions, spatial domain for material distribution, types of involved scalar fields and types of models for material distribution and composition of several materials points of view. In addition to the technical challenges of multi-material volume representations, a range of key challenges are considered before such representations can be adopted as mainstream practice

Modeling fruits and their internal structure using parametric 3Gmap L-systems

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