This thesis explores techniques for synthesizing crowds from imagery. Synthetic photorealistic crowds are desirable for cinematic gaming, special effects and architectural visualization. While motion captured-based techniques for the animation and control of crowds have been well-studied in computer graphics, the resulting control rig sequences require a laborious model-based graphics pipeline to render photorealistic videos of crowds. Over the past ten years, data-driven techniques for rendering imagery of complex phenomena have become a popular alternative to model-based graphics. This popularity is due in large part to difficulties in constructing the sufficiently-detailed models that are required to achieve photorealism. A dynamic crowd of humans is an extremely challenging example of such phenomena. Example-based synthesis methods such as video textures are an appealing alternative, but current techniques are unable to handle new challenges posed by crowds. This thesis describes how to synthesize video-based crowds by explicitly segmenting pedestrians from input videos of natural crowds and optimally placing them into an output video while satisfying environmental constraints imposed by the scene. There are three key challenges. First, the crowd layout of segmented videos must satisfy constraints imposed by environmental and crowd obstacles. This thesis addresses four types of environmental constraints: (a) ground planes in the scene which are valid for crowd traversal, such as sidewalks, (b) spatial regions of these planes where crowds may enter and exit the scene, (c) static obstacles, such as mailboxes and walls of a building, and (d) dynamic obstacles such as individuals and groups of individuals. Second, pedestrians and groups of pedestrians should be segmented from the input video with no artifacts and minimal interaction time. This is challenging in real world scenes due to significant appearance changes while traveling through the scene. Third, segmented pedestrian videos may not have enough frames or the right shape to compose a path from an artist-defined entrance to exit. Plausible temporal transitions between segmented pedestrians are therefore needed but they are difficult to identify and synthesize due to complex self occlusions. We present a novel algorithm for composing video billboards, represented by crowd tubes, to form a crowd while avoiding collisions between static and dynamic obstacles. Crowd tubes are represented in the scene using a temporal sequence of circles planted in the calibrated ground plane. The approach consists of representing crowd tube samples and constraint violations with a conflict graph. The maximal independent set yields a dense crowd composition. We present a prototype system for the capture, analysis, synthesis and control of video-based crowds. Several results demonstrate the system's ability to generate videos of crowds which exhibit a variety of natural behaviors.

<p>Three-dimensional computer graphics enjoys a wide range of applications of which games and movies are only few examples. By incorporating three-dimensional computer graphics in to a simulator the simulator is able to provide the operator with visual feedback during a simulation. Simulators come in many different flavors where flight and radar simulators are two types in which three-dimensional rendering of large terrains constitutes a central component.</p><p>Ericsson Microwave Systems (EMW) in Skövde is searching for an algorithm that (a) can handle terrain data that is larger than physical memory and (b) has an adjustable error metric that can be used to reduce terrain detail level if an increase in load on other critical parts of the system is observed. The aim of this paper is to identify and evaluate existing algorithms for terrain rendering in order to find those that meet EMW: s requirements. The objectives are to (i) perform a literature survey over existing algorithms, (ii) implement these algorithms and (iii) develop a test environment in which these algorithms can be evaluated form a performance perspective.</p><p>The literature survey revealed that the algorithm developed by Lindstrom and Pascucci (2001) is the only algorithm of those examined that succeeded to fulfill the requirements without modifications or extra software. This algorithm uses memory-mapped files to be able to handle terrain data larger that physical memory and focuses on how terrain data should be laid out on disk in order to minimize the number of page faults. Testing of this algorithm on specified test architecture show that the error metric used could be adjusted to effectively control the terrains level of detail leading to a substantial increase in performance. The results also reveal the need for both view frustum culling as well a level of detail algorithm to achieve fast display rates of large terrains. Further the results also show the importance of how terrain data is laid out on disk especially when physical memory is limited.</p>

<p>I denna studie undersöks två algoritmer för att rendera volumetrisk data. Studien syftar till att undersöka om det är möjligt att använda dessa algoritmer i en datorspelsmiljö. De båda algoritmerna, som kallas för shear-warp-algoritmen och footprint-algoritmen, jämförs mot varandra för att ta reda på vilken som är bäst på att lösa uppgiften. Algoritmerna testas också för att se om de är lämpade att verka i en datorspelsmiljö med avseende på om de kan generera tillräckligt antal bilder per sekund.</p><p>Resultatet av studien visar på att ingen av de två algoritmerna är lämpade inom den domän de är tänkta att verka inom. Även om shear-warp-algoritmen är effektivare på att lösa sin uppgift än vad footprint-algoritmen är så visar studien att ingen av dessa två algoritmer är lämpade i den domän de är undersökta i.</p>

<p>Computer gamers demand more realistic effects for each release of a new game. This final year project is concerned with deforming the geometry in a terrain rendering environment. The intension is to increase the resolution where the original resolution of the terrain is not enough to cater for all the details associated with a deformation, such as an explosion.</p><p>An algorithm for extending the maximum available resolution was found, the DEXTER algorithm, but calculations have shown that it has a too high memory consumption to be feasible in a game environment. In this project, an algorithm has been implemented, based on the DEXTER algorithm, but with some structural changes. The algorithm which has been implemented increases the resolution, if needed, where a deformation occurs. The increased resolution is described by b-spline surfaces, whereas the original resolution is given by a height map. Further, graphics primitives are only allocated to a high resolution region, when needed by the refinement process.</p><p>It has been found that by using dynamic blocks of graphics primitives, the amount of RAM consumed can be lowered, without a severe decrease in rendering speed. However, the algorithm implemented has been found to suffer from frame rate drops, if too many high resolution cells need to be attached to the refinement process during a single frame.</p><p>Is has been concluded that the algorithm, which is the result of this final year project, is not suitable for a game environment, as the memory consumption is still too high. The amount of time spent on refining the terrain can also be considered too much, as no time is left for other aspects of a game environment.</p><p>The algorithm is however considered a good choice concerning deformations, as the updates needed in association with a deformation, can be kept small and localized, according to the DEXTER structure. Also, the b-spline surfaces offer more freedom over the deformation, compared to using a height map.</p>

<p>Detta examensarbete omfattar konceptutvecklingen av en mättillsats för vattenkranen i köket, vars grundfunktion är att mäta mängden vatten. Syftet med produkten är att ersätta dagens användande av decilitermått vid vattenmätning, då decilitermåttet fortfarande fyller sin funktion inriktar sig arbetet på att utnyttja modern teknik för att med innovativa funktioner hitta nya omedvetna behov. Examensarbetet grundar sig på författarnas egen idé och behov av en sådan produkt, examensarbetet har utförts utan uppdragsgivare med handledning från tekniska högskolan i Jönköping.Rapporten beskriver hur arbetet har fortskridit från en idé till ett färdigt koncept med inriktning på designprocessen. Genomförandet innefattar att ett flertal koncept som har utvecklats med hjälp av metoder så som brainstorming och bygga-testa-metoden för att sedan sållas ut med hjälp av olika urvalsmetoder och resultera i ett slutgiltigt koncept.Det slutgiltiga konceptet resulterade i en mättillsatts som smälter in i det moderna köket. Hela konceptet har designats med målet att form ska följa funktion. Konceptet konstruerades både för att vara lätt att montera och använda. Resultatet av arbetet presenteras med renderingar och en fysisk presentationsmodell.</p> / <p>This report contains the concept development of measure device for a kitchen tap, the basic function is to measure the amount of water. The purpose with this product is to replace the current use of a handheld cup when measuring water, but since the measuring cup still fills its function much of the report is focused on using modern technology with innovative solutions to find unexpected needs. The report is based on the writers own idea and the need for such a product, the report has been conducted without contractor with guidance from School of Engineering at Jönköping University.The report describes how the process of an idea to a finished concept focused on the design process. The implementation involves numerous concepts that have been developed with the help of methods like brainstorming and build-test-method to later be screened of with different methods for screening to result in a final concept.The final concept resulted in a measuring device that blends well in to the modern kitchen. The concept has been developed with the idea that form should follow function. The concept was designed to be both easy to install and to use. The result is presented with renderings and a material presentation model.</p>

<p>Applikationen Chemical Force Feedback (CFF) för haptisk och visuell molekylrendering som har utvecklats på Linköpings Universitet för att testa nyttan av haptik för undervisning av protein-ligand dockning för molekylär livsvetenskap behöver förbättras på ett antal punkter för att bättre kunna fungera som ett komplett</p><p>molekylvisualiserings-verktyg. Tidigare projekt som utvecklat applikationen har fokuserat mestadels på den haptiska delen av programmet, vilket gjort att den visuella aspekten kommit efter. Det här examensarbetet har implementerat diverse ny funktionalitet både för att förbättra direkt kännbara aspekter av programmet, samt att lägga grunden för framtida utökningar.</p><p>De huvudsakliga förbättringarna som det här exjobbet resulterat i inkluderar: För det första, integration av DSSP-algoritmen i programmet har gjort information om sekundärstrukturen hos protein tillgänglig för visualisering. För det andra, ett nytt renderings-system tillåter rendering av semitransparenta ytor på ett korrekt sätt samtidigt som det skapar en program-struktur som bättre lämpar sig för implementation av nya molekylrepresentationer. För det tredje, en filvals-komponent som fungerar i den haptiska scengrafen har designats för att göra programmets användargränssnitt mer tillgängligt.</p> / <p>The Chemical Force Feedback (CFF) visual and haptic molecule rendering application, being developed at Linköping University to evaluate the use of haptics as a teaching tool for protein-ligand docking in molecular life science requires several additional features to function as a mature protein visualization tool. Previous developments of the application have focused mostly on the haptic part of the program, leaving the visual representation somewhat under-developed.</p><p>This thesis project has implemented various features in order to both improve the immediate functionality of the application as well as lay down the foundation for future additions.</p><p>The main contributions of this thesis include: Firstly, integration of the DSSP algorithm has provided the application with secondary structure information for the protein visualization. Secondly, a new rendering system has provided support for rendering transparent surfaces in a correct way as well as simplifying future addition of new visual representations of molecules. Thirdly, a file-selection dialog have been implemented using the haptic scenegraph as a step toward the goal of making the user interface of the application more user-friendly.</p>

Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 103-104). Also available on the World Wide Web.

Ray tracing is an attractive rendering option because it can produce high quality images that faithfully represent physically-based phenomena. Its embarrassingly parallel nature makes it a natural choice for rendering large-scale scene data, especially on machines that lack specialized graphics hardware. Unfortunately, the traditional recursive ray tracing algorithm is exceptionally memory inefficient for large scenes, especially when using a shading model that generates incoherent secondary rays. Queueing ray tracers have been shown to control scene state under these conditions, but they allow ray state to grow unchecked. Instead, we propose a ray tracing framework that controls both ray and scene state by dynamically adjusting the rendering algorithm to meet memory requirements. Our dynamic scheduling framework generalizes recursive and queueing tracers into a spectrum of ray schedules that can vary the active amount of ray and scene data in order to match the characteristics of the hardware’s memory system. This dissertation describes our dynamic ray scheduling approach that operates on memory-bound work units, which consist of both rays and scene data. It builds these work units by tracing rays iteratively and queueing them in spatial regions along with nearby data. By dynamically scheduling these work units, our approach can reduce data loads and improve total runtime by 2x to 30x . In addition, we show that our algorithm scales across more than 1000 distributed processors, which is an order of magnitude larger than previously published results. Our approach enables the use of complex lighting models on large data, particularly scientific data, which improves image quality and thereby improves the scientific insights possible. / text

Applikationen Chemical Force Feedback (CFF) för haptisk och visuell molekylrendering som har utvecklats på Linköpings Universitet för att testa nyttan av haptik för undervisning av protein-ligand dockning för molekylär livsvetenskap behöver förbättras på ett antal punkter för att bättre kunna fungera som ett komplett molekylvisualiserings-verktyg. Tidigare projekt som utvecklat applikationen har fokuserat mestadels på den haptiska delen av programmet, vilket gjort att den visuella aspekten kommit efter. Det här examensarbetet har implementerat diverse ny funktionalitet både för att förbättra direkt kännbara aspekter av programmet, samt att lägga grunden för framtida utökningar. De huvudsakliga förbättringarna som det här exjobbet resulterat i inkluderar: För det första, integration av DSSP-algoritmen i programmet har gjort information om sekundärstrukturen hos protein tillgänglig för visualisering. För det andra, ett nytt renderings-system tillåter rendering av semitransparenta ytor på ett korrekt sätt samtidigt som det skapar en program-struktur som bättre lämpar sig för implementation av nya molekylrepresentationer. För det tredje, en filvals-komponent som fungerar i den haptiska scengrafen har designats för att göra programmets användargränssnitt mer tillgängligt. / The Chemical Force Feedback (CFF) visual and haptic molecule rendering application, being developed at Linköping University to evaluate the use of haptics as a teaching tool for protein-ligand docking in molecular life science requires several additional features to function as a mature protein visualization tool. Previous developments of the application have focused mostly on the haptic part of the program, leaving the visual representation somewhat under-developed. This thesis project has implemented various features in order to both improve the immediate functionality of the application as well as lay down the foundation for future additions. The main contributions of this thesis include: Firstly, integration of the DSSP algorithm has provided the application with secondary structure information for the protein visualization. Secondly, a new rendering system has provided support for rendering transparent surfaces in a correct way as well as simplifying future addition of new visual representations of molecules. Thirdly, a file-selection dialog have been implemented using the haptic scenegraph as a step toward the goal of making the user interface of the application more user-friendly.

In the environmental design professions, many students and practitioners lack confidence in visual communication skills, especially in the case of quick perspective sketching. For many, sketching as a beneficial design tool is not fully learned or appreciated.This study explores sketching fundamentals and a teaching technique to promote perspective sketching as an effective design tool. Experimental workshops were conducted with various beginning environmental design students in three universities. Students responded to a post-workshop questionnaire which attempted to solicit feedback about the demonstrated sketching technique as to whether the technique 1) increased their ability, 2) increased their confidence, 3) increased their enjoyment, and 4) increased their willingness to pursue sketching in the future. Students were also evaluated on the degree of improvement according to simplicity, clarity and proper perspective setting of their sketches.The results suggested that the workshop, teaching methods and sketching techniques were successful. Students showed marked improvement and indicated in the questionnaire that they enjoyed the experience and were pleased with their new skills. They also indicated a positive feeling about the teaching methods and the sketching techniques. / Department of Landscape Architecture