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Im Bereich der Computergraphik bilden die Nicht-Photorealistischen Renderingverfahren einen Schwerpunkt in der technischen und wissenschaftlichen Visualisierung, vor allem aber in den künstlerischen Bereichen. Verschiedene Kunststile, sowie Zeichenmaterialien und ihre Eigenschaften stellen unterschiedliche Herausforderungen dar. Eine dieser Herausforderungen ist hierbei die Simulation flüssiger Zeichenmittel.
Diese Arbeit beschäftigt sich mit der Erstellung eines interaktiven Zeichensystems für ein flüssiges Zeichenmittel, der Aquarellmalerei. Für die Simulation wird eine raue Zeichengrundlage generiert, sowie die Fluid Simulation und das optische Farbverhalten der Aquarellmalerei implementiert.
Dynamisches Tone Mapping einer High Dynamic Range Echtzeit 3D-Umgebung mit der Grafik Hardware
(2007)
While Virtual Reality has been around for decades it gained new life in recent years. The release of the first consumer hardware devices allows fully immersive and affordable VR for the user at home. This availability lead to a new focus of research on technical problems as well as psychological effects. The concepts of presence, describing the feeling of being in the virtual place, body ownership and their impact are central topics in research for a long time and still not fully understood.
To enable further research in the area of Mixed Reality, we want to introduce a framework that integrates the users body and surroundings inside a visual coherent virtual environment. As one of two main aspects we want to merge real and virtual objects to a shared environment in a way such that they are no longer visually distinguishable. To achieve this the main focus is not supposed to be on a high graphical fidelity but on a simplified representation of reality. The essential question is, what level of visual realism is necessary to create a believable mixed reality environment that induces a sense of presence in the user? The second aspect considers the integration of virtual persons. Can characters be recorded and replayed in a way such that they are perceived as believable entities of the world and therefore act as a part of the users environment?
The purpose of this thesis was the development of a framework called Mixed Reality Embodiment Platform. This inital system implements fundamental functionalities to be used as a basis for future extensions to the framework. We also provide a first application that enables user studies to evaluate the framework and contribute to aforementioned research questions.
The goal of this thesis is to create and develop a concept for a mobile city guide combined with game-based contents.
The application is intented to support flexible and independent exploration of the city of Koblenz.
Based on the geographical data, historical information for and interesting stories of various places were provided in this application. These informations are combined with playful elements in order to create a motivating concept.
Therefore, related approaches were examined and, combined with own ideas, a new concept has been developed. This concept has been prototypically implemented as an Android application and afterwards evaluated by 15 test persons. A questionnaire was used to examine the operability, the motivation of game patterns and the additional value of the application.
In order to simulate realistic motion sequences, muscles must be able to be modelled anatomically correct. Yet it is only possible in SimPack to define muscles as a straight line between two points. This thesis presents an approach where ellipses can be defined through which a muscle must pass. The main problem is to calculate the length of this muscle through the ellipses. An algorithm is presented that calculates the shortest path of a muscle path through this ellipses. This algorithm is then implemented in Fortran 90 and integrated into an existing muscle model in SimPack.
In dieser Arbeit soll ein dreidimensionales, echtzeitfähiges Landschaftsmodell des Mittelrheintals erstellt werden. Dabei soll die Modellerstellung soweit wie möglich automatisiert werden. Als Datengrundlage dienen das digitale Landschaftsmodell ATKIS-Basis DLM sowie das digitale Geländemodell (DGM), welches die notwendigen Höheninformationen zur Erzeugung des dreidimensionalen Modells enthält. Insbesondere soll dabei untersucht werden, wie sich die Generierung von Landschaftsmerkmalen wie Infrastruktur und Vegetation durch ein parametrisierbares Modell automatisieren lässt, und inwieweit sich die verwendeten Daten für einen solchen Automatisierungsprozess eignen.
Artificial neural networks is a popular field of research in artificial intelli-
gence. The increasing size and complexity of huge models entail certain
problems. The lack of transparency of the inner workings of a neural net-
work makes it difficult to choose efficient architectures for different tasks.
It proves to be challenging to solve these problems, and with a lack of in-
sightful representations of neural networks, this state of affairs becomes
entrenched. With these difficulties in mind a novel 3D visualization tech-
nique is introduced. Attributes for trained neural networks are estimated
by utilizing established methods from the area of neural network optimiza-
tion. Batch normalization is used with fine-tuning and feature extraction to
estimate the importance of different parts of the neural network. A combi-
nation of the importance values with various methods like edge bundling,
ray tracing, 3D impostor and a special transparency technique results in a
3D model representing a neural network. The validity of the extracted im-
portance estimations is demonstrated and the potential of the developed
visualization is explored.
Im Laufe der Zeit fallen in einem Unternehmen große Mengen von Daten und Informationen an. Die Daten stehen im Zusammenhang mit unternehmensinternen Vorgängen, mit dem Marktumfeld, in dem das Unternehmen positioniert ist, und auch mit den Wettbewerbern. Sie sind vielfältiger Art, normalerweise inhomogen und aus verteilten Datenquellen zu beziehen. Um in dieser Flut von Daten die Übersicht zu behalten, die Menge an Informationen effektiv für das Unternehmen nutzbar zu machen, vor allem auch nachhaltig für kommende Entscheidungsfindungen, müssen die Daten analysiert und integriert werden. Diese Optimierung der Entscheidungsfindung durch Zugang zu Informationen, deren Analyse und Auswertung wird häufig unter dem Begriff "Business Intelligence" zusammengefasst. Der Wert der vorhandenen Informationen hängt stark von dem erwähnten Zugang und einer ausdrucksstarken Repräsentation ab. RIA-Techniken ermöglichen eine einfache Verfügbarkeit der verarbeiteten Geschäftsdaten über Inter- und Intranet ohne große Anforderungen an ihre Nutzbarkeit zu stellen. Sie bieten zudem spezialisierte leistungsfähige und in großem Maße programmierbare Visualisierungstechniken. Die Diplomarbeit soll zwei Schwerpunkte habe. Zum Einen wird sie sich mit Arten der Informationsvisualisierung im Allgemeinen und deren Eignung für Geschäfsdaten beschäftigen. Der Fokus liegt hierbei auf Daten und Informationen in Management-Informationsberichten. Ziel ist eine Visualisierungsform, die es dem Nutzer ermöglicht, die zu kommunizierenden Informationen effizient auszuwerten. Zum anderen untersucht die Diplomarbeit die Vor- und Nachteile des Einsatzes von RIAs. Der Implementierungsteil umfasst eine RIA als "Proof of Concept", deren Hauptaugenmerk auf eine dynamische Interaktion und optimierte Informationsvisualisierung gerichtet sein soll. Die Diplomarbeit wird bei der Altran CIS in Koblenz durchgeführt.
Real-time graphics applications are tending to get more realistic and approximate real world illumination gets more reasonable due to improvement of graphics hardware. Using a wide variation of algorithms and ideas, graphics processing units (GPU) can simulate complex lighting situations rendering computer generated imagery with complicated effects such as shadows, refraction and reflection of light. Particularly, reflections are an improvement of realism, because they make shiny materials, e.g. brushed metals, wet surfaces like puddles or polished floors, appear more realistic and reveal information of their properties such as roughness and reflectance. Moreover, reflections can get more complex, depending on the view: a wet surface like a street during rain for example will reflect lights depending on the distance of the viewer, resulting in more streaky reflection, which will look more stretched, if the viewer is locatedrnfarther away from the light source. This bachelor thesis aims to give an overview of the state-of-the-art in terms of rendering reflections. Understanding light is a basic need to understand reflections and therefore a physical model of light and its reflection will be covered in section 2, followed by the motivational section 2.2, that will give visual appealing examples for reflections from the real world and the media. Coming to rendering techniques, first, the main principle will be explained in section 3 followed by a short general view of a wide variety of approaches that try to generate correct reflections in section 4. This thesis will describe the implementation of three major algorithms, that produce plausible local reflections. Therefore, the developed framework is described in section 5, then three major algorithms will be covered, that are common methods in most current game and graphics engines: Screen space reflections (SSR), parallax-corrected cube mapping (PCCM) and billboard reflections (BBR). After describing their functional principle, they will be analysed of their visual quality and the possibilities of their real-time application. Finally they will be compared to each other to investigate the advantages and disadvantages over each other. In conclusion, the gained experiences will be described by summarizing advantages and disadvantages of each technique and giving suggestions for improvements. A short perspective will be given, trying to create a view of upcoming real-time rendering techniques for the creation of reflections as specular effects.
Helicopters are crucial in today’s life. A vast amount of applications prove
their range, which are not coverable by other types of aircraft. But they are
very complex systems, both, technically and physically. This is one of the
reasons why pilot training for helicopters is quite challenging. In the last
two decades flight simulators became a supplementary instrument in the
educational process of pilots. With flight simulators it is possible to replay
uncommon or dangerous situations. In this thesis a simple flight simulator
for helicopters will be developed based on rigid body physics. The foundation is a simplified rotor model which omits complex fluid dynamics. This
helps to keep the implementation simple and illustrative as well as provide simulation rates at real-time. The modules are implemented within
the Unreal Engine in such way, that changing helicopter characteristics is
very easy.
In der Computergrafik stellte die Berechnung von Reflexionen lange ein
Problem dar. Doch mit der ständigen Weiterentwicklung der Hardware
und Vorstellung neuer Verfahren ist eine realitätsnahe,
echtzeitfähige(durchschnittlich 60 FPS) Berechnung von Reflexionen möglich. In der folgenden Ausarbeitung werden verschiedene Reflexionsverfahren vorgestellt. Alle mathematischen und physikalischen Grundlagen werden gegeben, um die Algorithmen nachvollziehen zu können. Da eine Reflexion immer das Abtasten eines reflektierten Vektors bedeutet, werden zwei verschiedene Abtastungsverfahren für blickabhängige Reflexionen vorgestellt und anschließend implementiert. Zuletzt werden die Verfahren auf Basis von Qualität und Performance gegenübergestellt.
Ziel dieser Arbeit war es, ein (ggf. aus Teilverfahren zusammengesetztes) Gesamtsystem zur Generierung von Stadt- und Gebäudemodellen zu entwickeln und umzusetzen. Dabei war insbesondere wichtig, dass die baulichen Elemente einer Stadt durch realistisch wirkende, dreidimensionale Formen repräsentiert und auch in großer Anzahl unter Echtzeit-Bedingungen dargestellt werden können.
Ray Tracing als Bildsyntheseverfahren ist relevant für viele Anwendungsbereiche, da es Aspekte des Lichttransports physikalisch korrekt simulieren kann. Aufgrund des hohen Berechnungsaufwands sind der Einsatz von Datenstrukturen zur Beschleunigung und die parallele Verarbeitung notwendig. GPUs sind inzwischen hoch parallele, programmierbare Prozessoren mit zahlreichen Kernen und eignen sich aufgrund ihrer hohen Leistungsfähigkeit dazu, aufwändige, parallelisierbare Probleme zu lösen. In dieser Arbeit geht es um GPU Ray Tracing, beschleunigt durch Bounding Volume Hierarchien (BVH). Auf Basis relevanter Veröffentlichungen zu Aufbau und Traversierung von BVHs und der Abbildung des Ray Tracing Prozesses auf die GPU Architektur wird ein GPU Ray Tracer konzeptioniert und entwickelt. Während der BVH Aufbau vorab auf dem Host stattfindet, wird der gesamte Ray Tracing Prozess durch mehrere Kernel komplett auf der GPU ausgeführt. Die Implementierung der Kernel erfolgt in Form von OpenGL Compute Shader Programmen, und die Aufteilung des Ray Tracers auf mehrere Kernel ist durch die GPU Achitektur und das SIMT Ausführungsmodell motiviert. Für die Speicherorganisation der binären BVHs werden zwei Varianten betrachtet, klassisch und als MBVH, wobei sich die MBVH Organisation als effizienter erweist. Zudem werden verschiedene Varianten für die Traversierung ohne Stack und für die Stack-basierte Traversierung umgesetzt und bewertet. Der in mehrere Kernel strukturierte GPU Ray Tracer wird zudem mit einer Einzelkernel Version verglichen. Die besten Ergebnisse erreicht die Traversierung ohne Stack mit einem while-while Ablauf und MBVH im Rahmen des aufgeteilten GPU Ray Tracers.
This thesis presents a novel technique in computer graphics to simulate realtime
global illumination using path tracing. Path tracing is done with compute shaders on the graphics card (GPU) to perform rendering in a highly parallelized manner. To improve the overall performance of tracing rays, the Line Space is used as an acceleration data structure in different variations, resulting in better
empty space skipping. The Line Space saves scene information based on a previous voxelization in direction-dependent shafts and is generated and traversed on the GPU. With this procedure, indirect lighting and soft shadows can be computed in a physically correct way. Furthermore, using the Line Space, path tracing can be performed mostly independent of the complexity of the scene geometry with over 100 frames per second, which is truly real-time and much faster than using a comparable voxel grid. The image quality is not affected negatively by this technique and the shadow quality is in most cases much better compared to shadow-mapping.
A gonioreflectometer is a device to measure the reflection properties of arbitrary materials. In this work, such an apparatus is being built from easily obtainable parts. Therefore three stepper-motors and 809 light-emitting diodes are controlled by an Arduino microcontroller. RGB-images are captured with an industrial camera which serve as refelction data. Furthermore, a control software with several capture programs and a renderer for displaying the measured materials are implemented. These allow capturing and rendering entire bidirectional reflection distribution functions (BRDFs) by which also complex anisotropic material properties can be represented. Although the quality of the results has some artifacts due to shadows of the camera, these artifacts can be largely removed by using special algorithms like inpainting. In addition, the goniorefelctometer is applied to other use cases. One can perform 3D scans, light field capturing and light staging without altering the construction. The quality of these processes also meet the expectations in a positive way. Thus, the gonioreflectometer built in this work can be seen as a widely applicable and economical alternative to other publications.
This bachelor thesis deals with the development of an application for the Microsoft HoloLens. The application is used for the marketing of advertis- ing spaces that belongs to the company awk AUSSENWERBUNG GmbH. On basis of the development, the question is answered which are the pos- sibilities and limitations of the HoloLens and the Mixed Reality Platform. Problems are also addressed, that come along with the development of an application for such a new technology, like the HoloLens is. Beside the new technologies, some challenges come also from the applications oper- ational locations. Several application examples and presentations suggest, that the HoloLens is primarily designed for indoor usage. Instead the de- veloped application is for outdoor use only. During the development, sev- eral insights can be gained about this new technology. On the one hand it becomes clear, that the HoloLens and also the development environment aren’t completely matured yet. On the other hand, that the HoloLens isn’t an outdoor device at all. Despite the difficulties during the development, there occur many possibilities that are associated with this new technology.
In the context of augmented reality we define tracking as a collection of methods to obtain the position and orientation (pose) of a user. By means of various displaying techniques, this ensures a correct visual overlay of graphical information onto the reality perceived. Precise results for calculation of the camera pose are gained by methods of image processing, usually analyzing the pixels of an image and extracing features, which can be recognized over the image sequence. However, these methods do not regard the process of image synthesis or at least in a very simplyfied way. In contrast, the class of model-based methods assumes a given 3D model of the observed scene. Based on the model data features can be identified to establish correspondences in the camera image. From these feature correspondences the camera pose is calculated. An interesting approach is the strategy of analysis-by-synthesis, regarding the computer graphics rendering process for extending the knowledge about the model by information from image synthesis and other environment variables.
In this thesis the components of a tracking system are identified and further it is analyzed, to what extend information about the model, the rendering process and the environment can contribute to the components for improvement of the tracking process using analysis-by-synthesis. In particular, by using knowledge as topological information, lighting or perspective, the feature synthesis and correspondence finding should lead to visually unambiguous features that can be predicted and evaluated to be suitable for stable tracking of the camera pose.
Ziel dieser Arbeit ist es, markerloses Tracking unter dem Ansatz der Analyse durch Synthese zu realisieren und dabei auf den Einsatz merkmalsbasierter Verfahren zu verzichten. Das Bild einer Kamera und ein synthetisches Bild der Szene sollen durch den Einsatz von Stilisierungstechniken so verändert und angeglichen werden, dass zu dem gegebenen Kamerabild aus einer Auswahl von gerenderten Bildern jenes erkannt werden kann, welches die reale Kamerapose am exaktesten wiedergibt. Es werden Kombinationen von Ähnlichkeitsmaßen und Visualisierungen untersucht, um eine bestmögliche Vergleichbarkeit der Bilder zu erreichen, welche die Robustheit gegen Trackingfehler erhöhen soll.
In this bachelor thesis a code for astrophysical self-gravitating fluid
simulation is developed. The code runs mainly on the GPU. Minimal
simplifications of the physical model and some parameters for accuracy
and tuning allow simulations to be performed at interactive framerates
on most modern consumer grade computers that feature a dedicated
graphics card. It is used to simulate the birth of stars from a turbulent
molecular cloud. Multiple features of star formation, like accretion
discs and fragmentation, can be observed in the simulation, even when
low particle counts are used.
The present thesis describes the development of an OpenGL-based tool visualizing cavities of proteins, which can be observed during a static docking simulation. The goal is to achieve knowledge about interactions between proteins and ligands based on information about distances between them. At first chemical basics, which motivate the topic and are important for understanding the topic and the used algorithms, are presented. Furthermore existing software, which deals with similar issues, is described. Next the prerequisites for the development of the program are presented and the tool is described in detail. Concluding the tool is evaluated concerning performance and usage and a summarizing conclusion is given. The program turns out as a helpful tool for current research and a good base for further and deeper research projects.
Algorithmische Komposition
(2018)
Algorithmic composition is an interdisciplinary topic that unites music and science. The computer is able to generate algorithmic music with the aid of a specific algorithm. In this bachelor thesis, algorithmic composition is realized with the biology-inspired algorithms called Lindenmayer-system and cellular automaton. In order to realize the compositions, several techniques are presented as well as implemented and evaluated. Those techniques map the generated data from the algorithms on a meaningful musical result.
Point Rendering
(2021)
In this thesis different methods for rendering point data are shown and compared with each other. The methods can be divided into two categories. For one visual methods are introduced that strictly deal with the displaying of point primitves. The main problem here lies in the depiction of surfaces since point data, unlike traditional triangle meshes, doesn't contain any connectivity information. On the other hand data strucutres are shown that enable real-time rendering of large point clouds. Point clouds often contain large amounts of data since they are mostly generated through 3D scanning processes such as laser scanning and photogrammetry.
This thesis explores different approaches for the acceleration of raytracing calculations on the graphics processing unit (GPU). For that a voxel grid is used and extended by the linespace data structure. The linespace consists of direction based shafts and stores the objects located in those shafts in a candidate list. Different methods for the sorting and traversal of the linespace are presented and evaluated. The shown methods cannot provide a speed up of the frame rate without resulting in a loss of image quality.
Konzept und Umsetzung eines E-Learning Nähkurses mit Integration von 3D-Modellen und Animationen
(2007)
Die Medizinische Visualisierung komplexer Gefäßbäume hat das Potential den klinischen Alltag in der Gefäßchirurgie zu erleichtern.
Dazu sind exakte, hochaufgelöste Darstellungen und echtzeitfähige Berechnungsmethoden notwendig. Bekannte Ansätze aus den Bereichen der direkten (z.B. Raycasting) und indirekten
(z.B. Marching Cubes) Volumenvisualisierung sind nicht in der Lage alle Anforderungen zufriedenstellend zu erfüllen. Verbesserte
Ergebnisse können mit hybriden Methoden erzielt werden, die unterschiedliche Visualisierungsverfahren kombinieren.
Im Rahmen dieser Arbeit wurde ein hybrides Renderingsystem zur Darstellung von Blutgefäßen entwickelt, das die Bildqualität durch Integration einer Marching Cubes Oberfläche in ein Raycasting–System optimiert, dabei Detailstrukturen erhält und ausreichende Performanz zur Interaktion bietet. Die Ergebnissezeigen die verbesserte Plastizität und Genauigkeit der Darstellung.Anhand von Experten– und Laienbefragungen konnte der Nutzen des Systems vor allem für die Patientenaufklärung nachgewiesen werden. Die Erschließung zusätzlicher Anwendungsgebiete ist durch die Weiterentwicklung des Renderers möglich.
In dieser Arbeit wird die Konzeption, Implementierung und Evaluierung einer Augmented Reality-App beschrieben. Diese wurde mit dem Ziel entwickelt, Objekte im realen Raum mit virtuellen Hilfsmitteln auszumessen, sodass diese Anwendung einen Holzgliedermaßstab ersetzen kann. Hinzu kommt die praktische Speicherung der Messwerte. Angefertigt wurde die App mit der Unity Engine und programmiert in C#.
Schwerpunkte dieser Arbeit sind die Benutzerfreundlichkeit der App, sowie die Eignung von AR Foundation für das Ausmessungstool.
Die Anwendung wird auf die genannten Kriterien im Rahmen eines Nutzertests in einer abschließenden Evaluation bewertet.
Als Ergebnis ließ sich festhalten, dass sich die AR-App noch im Prototyp-Stadium befindet, aber im Allgemeinen schon als benutzerfreundlich gilt. Kleinere Änderungen sollen und müssen noch vorgenommen werden, um auch den Umgang mit dem AR-Tool zu vereinfachen.
The aim of this work is to develop a simple concept for monitoring dogs that are alone at home for several hours. The prototypical implementation of such a "DogCam" can be considered as proof of concept. The basis for the prototype‘s implementation are the requirements identified within a conducted requirement analysis. Furthermore, the present work shows which improvements and extensions of the prototypical "DogCam" are possible and which similar projects already exist.
Für die realistische Betrachtung einer virtuellen Szene spielt neben der direkten Beleuchtung auch die Ausbreitung des indirekten Lichtes eine wichtige Rolle. Die Berechnung der indirekten Beleuchtung benötigt grundsätzlich Informationen über die gesamte Szene, nicht nur über den für die Kamera sichtbaren Ausschnitt, der in bildraumbasierten Techniken zum Einsatz kommt. Mittels Voxelisierung kann die Szene in eine dreidimensionale, diskrete und GPU-freundliche Repräsentation überführt werden. In dieser Arbeit werden Voxelrepräsentationen hinsichtlich ihrer Eignung für den globalen Lichtaustausch in dynamischen und großen Szenen untersucht. Nach einer Einführung und einem Literaturüberblick über existierende Voxelisierungs- und Beleuchtungsverfahren, die Voxel als Grundlage nutzen, wird ein Voxelisierungsverfahren entwickelt, das sich für Szenen mit dynamischen Objekten eignet. Auf der Grundlage des Strahlenschnitt-Tests mit binärer Voxelhierarchie werden dann zwei Beleuchtungsalgorithmen umgesetzt, implementiert und evaluiert: Monte-Carlo-Integration der Hemisphäre eines Szenenpunktes und Beleuchtung der Szenenpunkte mit virtuellen Punktlichtquellen.
Augmented reality is being present for many years. Through progress in technology smaller augmented reality glasses became possible. These new technologies allow many new ways of interaction and usage of augmented reality.
This thesis is about the Microsoft HoloLens and its possiblities for consumers and industry. In the context of this thesis a new interactive and augmented application to measure the possiblities and limitations of the Microsoft HoloLens has been developed. The scene is an assembly szenario with a step by step instruction of building with Lego bricks. The evaluation showed that the HoloLens can already be used to assist in assembling scenarios and offers some advantages over other methods, although the glasses still have some flaws.
The following work describes the prototypical conception and development of the stat-raising game "Adventurer's Guild" using the game engine Ren'Py. The game's narrative is influenced by player decisions and the planning of activities. The game is to be visually pleasing and enjoyable.
After giving an overview of stat-raising as a genre, the existing games "Dandelion - Wishes Brought to You", "Pastry Lovers", "Long Live the Queen" and "Magical Diary" are analysed to pinpoint various strengths and weaknesses of their different takes on the genre.
The resultant findings are used for the conception of a new stat-raising game.
The game mechanics and the design decisions made are then shown in screenshots and thoroughly explained.
In a final assessment, the game will be examined with regard to the given task. Further possibilities for potential improvements and expansions will be detailed at the end.
Implementierung eines Subsurface Scattering Shader Plugins für die Augenblick Raytracing Engine
(2009)
In dieser Ausarbeitung werden drei Beleuchtungsverfahren und mögliche Implementierungen zur Realisierung eines Subsurface Scattering Shaders vorgestellt und diskutiert. Subsurface Scattering bezeichnet allgemein den Lichttransport in die Oberfläche von Objekten hinein und durch sie hindurch. Die korrekte Darstellung dieses Phänomens ist sehr komplex und ist nicht mittels einer einfachen BRDF und gängiger Beleuchtungsverfahren darstellbar. Die drei Verfahren sind: Physikalisch korrektes Subsurface Scattering durch das Monte Carlo Pathtracing, vereinfachtes Subsurface Scattering durch Nutzung eines Licht-Lots, stark vereinfachtes Subsurface Scattering durch ein normalenabhängiges Aufhellen der Kanten. Durch die Nutzung des Monte Carlo Pathtracers können zudem Beleuchtungseffekte wie das sogennante Colorbleeding, dass heißt Lichttransport von einer farbigen Fläche auf eine andere mittels indirekter Beleuchtung, ermöglicht werden. Jedes Verfahren beinhaltet eine andere Kombination der bekanntlich gegenläufigen Eigenschaften Performanz und Korrektheit, je nachdem in welchem Rahmen und Aufgabenbereich Subsurface Scattering benötigt wird.Am Schluss der Arbeit werden Ergebnisse präsentiert, diskutiert und ein Ausblick auf weiterführende Arbeiten gegeben. Alle drei Verfahren wurden als Plugin für den Raytracer Augenblick von Oliver Abert realisiert.
This work represents a quantitative analysis and visualisation of scar tissue of the left ventricular myocard. The scar information is shown in the late enhancement data, that highlights the avitale tissue with the help of a contrast agent. Through automatic methods, the scar is extracted from the image data and quantifies the size, location and transmurality. The transmurality shows a local measurement between the heart wall und the width of the scar. The developed methods help the cardiologist to analyse the measurement, the reason and the degree of the heart failure in a short time period. He can further control the results by several visual presentations. The deformation of the scar tissue over the heart cycle is implemented in another scientific work. A visual improvement of the deformation result which extracts the scar out of the data is aspired. The avital tissue is shown in a more comfortable way by eliminating the unnecessary image information and therefore improves the visual analysis of the pumping heart. Both methods show a detailed analysis of the scar tissue. This supports the clinic practical throughout the manual analysis.
Deformable Snow Rendering
(2019)
Accurate snow simulation is key to capture snow's iconic visuals. Intricate
methods exist that attempt to grasp snow behaviour in a holistic manner. Computational complexity prevents them from reaching real-time performance. This thesis presents three techniques making use of the GPU that focus on the deformation of a snow surface in real-time. The approaches are examined by their ability to scale with an increasing number of deformation actors and their visual portrayal of snow deformation. The findings indicate that the approaches maintain real-time performance well into several hundred individual deformation actors. However, these approaches each have their individual restrictions handicapping the visual results. An experimental approach is to combine the techniques at reduced deformation actor count to benefit from the detailed, merged deformation pattern.
This bachelor thesis deals with the conception, implementation and evaluation of a Jump'n'Run game and the consideration of the influence of achievment systems on players. In the game Age of Tunes you play Bardur, the beardless bard and have to try to free the cursed magical creatures in the world Harmonica. The emphasis of the thesis was the clean conception and gradual development of the game, appealing graphic quality, integration of opponents, a mini-game and the consideration of effects of an achievment system on players. In a final evaluation the game and the behavior could be evaluated regarding the achievments.
Clubs, such as Scouts, rely on the work of their volunteer members, who have a variety of tasks to accomplish. Often there are sudden changes in their organization teams and offices, whereby planning steps are lost and inexperience in planning occurs. Since the special requirements are not covered by already existing tools, ScOuT, a planning tool for the organization administration, is designed and developed in this work to support clubs with regard to the mentioned problems. The focus was on identifying and using various suitable guidelines and heuristic methods to create a usable interface. The developed product was evaluated empirically by a user survey in terms of usability.
The result of this study shows that already a high degree of the desired goal could be reached by the inclusion of the guidelines and methods. From this it can be concluded that with the help of user-specific concept ideas and the application of suitable guidelines and methods, a suitable basis for a usable application to support clubs can be created.
In dieser Arbeit wird ein System zur Erzeugung und Darstellung stereoskopischen Video-Panoramen vorgestellt. Neben der theoretischen Grundlagen werden der Aufbau und die Funktionsweise dieses Systems erläutert.
Dazu werden spezielle Kameras verwendet, die Panoramen aufnehmen
können und zur Wiedergabe synchronisiert werden. Anschließend wird ein Renderer implementiert, welcher die Panoramen mithilfe einer VirtualReality Brille stereoskopisch darstellen kann. Dafür werden separate Aufnahmen für die beiden Augen gemacht und getrennt wiedergegeben. Zum Abschluss wird das entstandene Video-Panorama mit einem Panorama eines schon bestehenden Systems verglichen.
The present thesis gives an overview of the general conditions for the programming of graphics cards. For this purpose, the most important Application Programming Interfaces (APIs) available on the market are presented and compared. Subsequently, two standard algorithms from the field data processing, prefix sum and radixsort are presented and examined with regard to the implementation with parallel programming on the GPU. Both algorithms were implemented using the OpenGL-API and OpenGL compute shaders. Finally, the execution times of the two algorithms were compared.
With the appearance of modern virtual reality (VR) headsets on the consumer market, there has been the biggest boom in the history of VR technology. Naturally, this was accompanied by an increasing focus on the problems of current VR hardware. Especially the control in VR has always been a complex topic.
One possible solution is the Leap Motion, a hand tracking device that was initially developed for desktop use, but with the last major software update it can be attached to standard VR headsets. This device allows very precise tracking of the user’s hands and fingers and their replication in the virtual world.
The aim of this work is to design virtual user interfaces that can be operated with the Leap Motion to provide a natural method of interaction between the user and the VR environment. After that, subject tests are performed to evaluate their performance and compare them to traditional VR controllers.