Im folgenden finden Sie eine Übersicht der angebotenen Themen. Nahezu alle Quellen sind auf englisch, sowie die Themenbeschreibung. Die Arbeit selber darf in deutsch gehalten werden, jedoch wird empfohlen den Vortrag in englischer Sprache zu halten. Selbiges gilt für die Ausarbeitung.

Real Time Forest Rendering

Category: Real Time Rendering, Rendering Methods, Large Scale Visualization

Brief Description of the topic:

Visualizing a huge amount of complex models can be a time consuming part of the rendering process.  For many complex objects specialized methods exist. This seminar topic is about the realtime visualization of forests.

Rendering forests can be a time consuimg task making it hard to find a method that is capable of rendering many trees in real time while maintining a decent visual quality. To achieve interactive framerates many methods introduce simplifications that lead to so called popping artifacts that distract the user and lower the immersion.

In recent years many advances and the development of modern graphics hardware lead to more elaborated methods which are capable of processing and rendering millions of trees in real time and with popping artifacts and convincing lighting effects.

Task: 

Describe recent advances in the filed of Real Time Forest Rendering, the techniques used and discuss shortly the history of existing methods.

Deformable Models Basics

Category: Physical Simulation, Numerics

Brief description of the topic:

Physically based deformable models include a huge variety of applications. Those range from fluid and smoke animation, fracture calculation to cloth simulations. All this physical systems can be described by partial differential equations (PDE). For those elaborated numerical method exist. But each application has specific requirements to the accuracy and to the speed of the simulation. This lead to the development of many different but specialized methods for simulating deformable models.

A few general concepts exist which are neccessary for the simulation of deformable models like Hooke's Law, the elasticity formulation for continuous objects and the Navier-Stokes equations.

Task:

Describe the basic concepts for deformable Models and discuss numerical mesh based methods to solve the underlying PDEs. You should have a look into the Survey "Physically Based Deformable Models in Computer Graphics" written by Andrew Nealen et al in 2005 for the Eurographics.

Meshless Deformable Models

Category: Physical Simulation, Numerics

Brief description of the topic:

Physically based deformable models include a huge variety of applications. Those range from fluid and smoke animation,    fracture calculation to cloth simulations. All this physical systems can be described by partial differential equations (PDE).    For those elaborated numerical method exist. But each application has specific requirements to the accuracy and to the speed of the simulation. This lead to the development of many different but specialized methods for simulating deformable models.

Popular methods in fluid dynamics work without a mesh and are especially capable of simulating physical systems without fixed neighbour information.

Task: 

Describe methods for solving the underlying PDEs of a physical system without a mesh, concentrate on fluid dynamics. Describe the problems and extensions of those methods. You should have a look into the Survey "Physically Based Deformable Models in Computer Graphics" written by Andrew Nealen et al in 2005 for the Eurographics to get an overview. 

Simulating Rods – Deformable Models

Category: Physical Simulation, Numerics

Brief description of the topic:

Physically based deformable models include a huge variety of applications. Those range from fluid and smoke animation,    fracture calculation to cloth simulations. All this physical systems can be described by partial differential equations (PDE).    For those elaborated numerical method exist. But each application has specific requirements to the accuracy and to the speed of the simulation. This lead to the development of many different but specialized methods for simulating deformable models.

Interesting deformable models are elastic rods. Complex phenomena emerge after applying simple deformations like twisting the rod. Those require a more elaborated model to reach the neccessary amount of realism.

Task: 

Describe what is required beyond the usual methods to model an elastic rod. Recent findings could create convincing models which can reproduce the complex behaviour of a rod. Describe the problems and extensions of those methods. You should have a look into the Survey "Physically Based Deformable Models in Computer Graphics" written by Andrew Nealen et al in 2005 for the Eurographics to get an overview. 

Simulating Shells – Deformable Models

Category: Physical Simulation, Numerics

Brief description of the topic:

Physically based deformable models include a huge variety of applications. Those range from fluid and smoke animation,    fracture calculation to cloth simulations. All this physical systems can be described by partial differential equations (PDE).    For those elaborated numerical method exist. But each application has specific requirements to the accuracy and to the speed of the simulation. This lead to the development of many different but specialized methods for simulating deformable models.

Structural rigid physical systems are numerically challenging like e.g. thin shells. It is important to choose the right methods to achieve the neccessary amount of accuracy to accommodate for the physical nature of shells.

Task: 

Describe what approaches are capable of simulating structural rigidit systems and how the differ from existing methods for non rigid system like textiles. Investigate what methods are used in state of the art models. You should have a look into the Survey "Physically Based Deformable Models in Computer Graphics" written by Andrew Nealen et al in 2005 for the Eurographics to get an overview. 

Design of Tangent Vector Fields

Category: Numerics, Mathematical Methods

Brief description of the topic:

Tangent vector fields are an essential ingredient in controlling surface appearance for applications ranging from anisotropic shading to texture synthesis and non-photorealistic rendering. To achieve a desired effect one is typically interested in smoothly varying fields that satisfy a sparse set of user-provided constraints. Using tools from Discrete Exterior Calculus, it is possible to create a simple and efficient algorithm for designing such fields over arbitrary triangle meshes. By representing the field as scalars over mesh edges (i.e., discrete 1-forms), an intrinsic, coordinate-free formulation can be obtained in which field smoothness is enforced through discrete Laplace operators. Unlike previous methods, such a formulation leads to a linear system whose sparsity permits efficient pre-factorization. Constraints are incorporated through weighted least squares and can be updated rapidly enough to enable interactive design. [http://www.multires.caltech.edu/pubs/VFDesign.pdf]

Task:

Describe the ideas and methods described in the Paper. Explain the neccessary mathematical background.

 

Multiscale Visualization for biological data

Category: Multiscale Visualization, Medical Visualization

Brief Description of the topic:

Processes in the human body occur at different scales (from metres to nanometres, from microseconds to decades). Thus, there is a need for visualisation techniques that can support transition from one scale to another (for example, between organs, tissues and cells) in unified way.

Multiscale spatial visualisations have previously been developed in other areas, such as  cartography, GIS and astrophysics. Despite several calls for multiscale visualization  in the biomedical field, and the exponential increase in the size and complexity of their datasets, in recent years there have been several projects related to the multiscale spatial visualization in the field of biomedicine.

Task:

Describe how multiscale spatial techniques are used in the field of medical data visualization in recent projects, explaining the requirements of each project and how the use of these techniques satisfied that need.