Denna rapport ar resultatet av ett examensarbete som har utforts vid institutionen for informationsoch kommunikationsteknik, Kungliga Tekniska Hogskolan (KTH), och omfattar 15 hp. Rapporten presenterar ett arbete dar examensarbetarna har utvecklat en terrang med hojdskillnader och ljussattning, partikeleffekter (CPU-GPU implementering) som liknar ett fyrverkeri, partikeleffekter (GPU implementering) som visar olika monster samt en kamera for att kunna observera spelvarlden fran alla mojliga olika vinklar i 3D med API:et Lightweight Java Game Library (LWJGL). LWJGL ar ett lagniva-API som riktar sig mot nyborjare och professionella spelutvecklare i programspraket Java. Flera tekniker exponeras istallet for att mappa lagniva-funktioner i objektorienterad programmeringsparadigm som manga javautvecklare ar vana vid. LWJGL hanterar sin egen grafik, ljud och styrkontroller enbart for att fa en solid grund for moderna spel och en battre anvandarupplevelse. Den grafiska renderingen skots med OpenGL. Syftet med det har examensarbetet var att utvardera LWJGL om den ar kompetent nog att anvandas i samband med spelutveckling. Det ar kant att Java Standard Edition (Java SE) har valdigt daligt stod for grafikintensiva och komplexa applikationer dar prestandan ar valdigt viktig. Darfor utvecklade vi en storre grafiskt kravande applikation, for att kunna gora en samlad bedomning om hur det ar att arbeta med LWJGL och vad det erbjuder en spelutvecklare. Arbetet delades upp i tre olika faser. Den forsta fasen borjade med att skapa en kravspecifikation for den produkt som skulle utvecklas, den lag till grund for hela arbetet. Nasta steg var datainsamling med syfte att erhalla forstaelse for olika tekniker och att identifiera problem. Den tredje fasen var sjalva utforandet dar vi designade, implementerade, testade och analyserade losningarna iterativt. Rapporten ger lasaren en oversikt over de krav som stallts pa prototypen, den projektmetod som anvants, tekniker som har tillampats, alla losningar som har tagits fram och varfor LWJGL blev utvald bland manga andra. Enligt de tester som utforts sa ar partikelsystem A (CPU-GPU implementering) bra mycket langsammare an partikelsystem B (GPU implementering) rent prestandamassigt. Nar 1,5 miljoner partiklar renderades sa fick partikelsystem A 5 bilder per sekund och partikelsystem B 110 bilder per sekund. Ingenjorsmassiga metoder och standarder har anvants under hela arbetets forlopp som forvarvats under civilingenjorsutbildningen informationsteknik pa KTH med inriktning datalogi. Det innefattar agil systemutveckling, programmering och problemlosning. Goda kunskaper i Java, matematik och allman IT-teknisk bakgrund forutsatts for att hanga med i alla resonemang i denna rapport. / This report is the result of a thesis work done at the Department of Information and Communication Technology, Royal Institute of Technology (Swedish: Kungliga Tekniska hogskolan, abbreviated KTH), and includes 15 credits. The report presents a work in which graduate students have developed a terrain with elevation changes and lighting, particle effects (CPU-GPU implementation) displaying fireworks, particle effects (GPU implementation) which displays different patterns as well as a camera in order to observe the game world from all sorts of different angles in 3D utilizing the API Lightweight Java Game Library (LWJGL). LWJGL is a low-level API that targets beginners and professional game developers alike in the Java programming language. Several technologies are exposed instead of mapping low-level features of object-oriented programming paradigm, which many Java developers are used to. LWJGL handles its own graphics, sound and controllers just to get a solid foundation for the modern game and an improved user experience. The graphical rendering is handled using OpenGL. The aim of this thesis was to evaluate LWJGL if it is competent enough to be used in conjunction with game development. It is known that the Java Standard Edition (Java SE) has very poor support for graphics-intensive and complex applications where performance is very important. Therefore, we developed a more graphically demanding application, in order to make an overall assessment of how it is to work with LWJGL and what it offers game developers. The work was divided into three different phases. The first phase began with creating a specification for the product to be developed which became the basis of the whole work. The next step was data collection with the objective to obtain an understand the different technologies and identify problems. The third phase was the actual execution where we designed, implemented, tested and analyzed solutions iteratively. The report provides the reader with an overview of the requirements imposed on the prototype, the project methodology, technologies that have been applied, all the solutions that have been developed and why LWJGL was chosen among many others. According to the tests conducted, particle system A (CPU-GPU implementation) is much slower than particle system B (GPU implementation) purely performance-wise. When 1,5 million particles were rendered, particle system A got 5 Frames per second (FPS) and particle system B 110 FPS. Engineering methods and standards were used throughout the work process acquired during the Information Technology Engineering degree at KTH majoring in computer science. It includes agile systems development, programming and problem solving. Good knowledge of Java, mathematics and a general IT technical background is required to keep up with all the information in this report.

Surface modelling and editing is one of important subjects in computer graphics. Decades of research in computer graphics has been carried out on both low-level, hardware-related algorithms and high-level, abstract software. Success of computer graphics has been seen in many application areas, such as multimedia, visualisation, virtual reality and the Internet. However, the hardware realisation of OpenGL architecture based on FPGA (field programmable gate array) is beyond the scope of most of computer graphics researches. It is an uncultivated research area where the OpenGL pipeline, from hardware through the whole embedded system (ES) up to applications, is implemented in an FPGA chip. This research proposes a hybrid approach to investigating both software and hardware methods. It aims at bridging the gap between methods of software and hardware, and enhancing the overall performance for computer graphics. It consists of four parts, the construction of an FPGA-based ES, Mesa-OpenGL implementation for FPGA-based ESs, parallel processing, and a novel algorithm for surface modelling and editing. The FPGA-based ES is built up. In addition to the Nios II soft processor and DDR SDRAM memory, it consists of the LCD display device, frame buffers, video pipeline, and algorithm-specified module to support the graphics processing. Since there is no implementation of OpenGL ES available for FPGA-based ESs, a specific OpenGL implementation based on Mesa is carried out. Because of the limited FPGA resources, the implementation adopts the fixed-point arithmetic, which can offer faster computing and lower storage than the floating point arithmetic, and the accuracy satisfying the needs of 3D rendering. Moreover, the implementation includes Bézier-spline curve and surface algorithms to support surface modelling and editing. The pipelined parallelism and co-processors are used to accelerate graphics processing in this research. These two parallelism methods extend the traditional computation parallelism in fine-grained parallel tasks in the FPGA-base ESs. The novel algorithm for surface modelling and editing, called Progressive and Mixing Algorithm (PAMA), is proposed and implemented on FPGA-based ES’s. Compared with two main surface editing methods, subdivision and deformation, the PAMA can eliminate the large storage requirement and computing cost of intermediated processes. With four independent shape parameters, the PAMA can be used to model and edit freely the shape of an open or closed surface that keeps globally the zero-order geometric continuity. The PAMA can be applied independently not only FPGA-based ESs but also other platforms. With the parallel processing, small size, and low costs of computing, storage and power, the FPGA-based ES provides an effective hybrid solution to surface modelling and editing.

<p>At Saab Aerosystems, situated in Linköping Sweden, there is a presentation and manoeuvre simulator simulating the fighter jet JAS-39 Gripen. This flight simulator is called PMSIM. In this thesis we study how to transfer sensor images generated by PMSIM to other simulators or desktop computers. The transmission is band-limited so some kind of image coding must be used. Because of this the greater part of this thesis is concerned with image coding. </p><p>To fulfill the real time requirement the image coding has to be quite simple and the transmission has to be fast. To achieve fast transmission the network protocol has to use as little overhead information as possible. Such a protocol has therefore been designed and implemented. </p><p>This report also includes a survey about real radio links. This survey investigates how the quality of the video stream can be affected by noise and other disturbing elements. </p><p>The work in this report revolves around the implementation of a video link. The purpose of this link is to transmit and display sensor images. The link consists mainly of the three following parts: image coder, network link and image player. The image coding has been focused on MPEG and wavelets. </p><p>The wavelet technique is not a well known coding principle for video applications. Although as a coding technique for still images the technique is well known. For instance it is used in the JPEG2000-standard. Experiments conducted and published in this report suggest that for some applications the wavelet technique can be a viable candidate, with respect to the MPEG technique, for a video coder.</p>

The purpose of this thesis is the development of an interactive computer-generated rendering system that provides artists with the ability to create abstract paintings simply and intuitively. This system allows the user to distort a computer-generated environment using image manipulation techniques that are derived from fundamentals of expressionistic art. The primary method by which these images will be abstracted stems from the idea of several small images assembled into a collage that represents multiple viewing points rendered simultaneously. This idea has its roots in the multiple-perspective and collage techniques used by many cubist and futurist artists of the early twentieth century.

At Saab Aerosystems, situated in Linköping Sweden, there is a presentation and manoeuvre simulator simulating the fighter jet JAS-39 Gripen. This flight simulator is called PMSIM. In this thesis we study how to transfer sensor images generated by PMSIM to other simulators or desktop computers. The transmission is band-limited so some kind of image coding must be used. Because of this the greater part of this thesis is concerned with image coding. To fulfill the real time requirement the image coding has to be quite simple and the transmission has to be fast. To achieve fast transmission the network protocol has to use as little overhead information as possible. Such a protocol has therefore been designed and implemented. This report also includes a survey about real radio links. This survey investigates how the quality of the video stream can be affected by noise and other disturbing elements. The work in this report revolves around the implementation of a video link. The purpose of this link is to transmit and display sensor images. The link consists mainly of the three following parts: image coder, network link and image player. The image coding has been focused on MPEG and wavelets. The wavelet technique is not a well known coding principle for video applications. Although as a coding technique for still images the technique is well known. For instance it is used in the JPEG2000-standard. Experiments conducted and published in this report suggest that for some applications the wavelet technique can be a viable candidate, with respect to the MPEG technique, for a video coder.

In Geographic Information System (GIS) applications, aster data constitutes one of the major data types. The displaying of the raster data has an important part in GIS applications. Digital Terrain Elevation Data (DTED) is one of the raster data types, which is used as the main data source in this thesis. The DTED data is displayed on the screen as digital images as a pixel value, which is represented in gray scale, corresponding to an elevation (texel). To draw the images, the texel values are mostly interpolated in order to perform zoom-in and/or zoom-out operations on the concerned area. We implement and compare four types of interpolation methods, nearest neighbor, bilinear interpolation, and two new proposed interpolation methods (1) 4-texel weighted average and (2) 8-texel weighted average. The real-time graphical display, with zoom-in/zoom-out capabilities, has also been implemented by buffering DTED data in memory and using a C++ clas that manages graphical operations (zoom-in, zoom-out, and 2D, 3D isplay) by using Windows GDI+ and OpenGL graphic ibraries resulting in 30-40 framesper-second for one grid of DTED Level 0 data.

<p>Visualization is a rapidly growing area of computer graphics. Due to the very progressive development of computer technology and especially 3D-graphic boards yesterdays imagination of visualizations, today is a reality. </p><p>At Saab Bofors Dynamics in Linköping missile systems are developed. Through the development, different subsystems are simulated before the manufacturing starts. The results of these simulations have to be visualized to get a meaning. The visualizations can be symbolic or more real looking 3D-visualizations. </p><p>During the work an investigation of available tools for computer visualizations on the market has been conducted. The outcome of the investigation has later been the foundation for the selection of tools to solve the visualization task. </p><p>One 3D-visualization application for general 3D-visualization has then been developed using two different 3D-APIs, and the experiences of these have then been analyzed.</p>

Diese Arbeit beschreibt den Entwurf und die Funktionsweise einer parallelen OpenGL-Renderingschnittstelle, die den effizienten Betrieb unmodifizierter graphischer Anwendungen auf segmentierten Anzeigen ermöglicht. Diese Schnittstelle integriert sich vollständig in eine verteilte graphische Benutzeroberfläche. Die herausragende Eigenschaft der entwickelten parallelen OpenGL-Schnittstelle ist ihre gleich bleibende Bildrate bei wachsender Anzahl von Segmenten. Als Erweiterung des frei verfügbaren Chromium-Systems stellt die Implementation eine virtuelle Graphikpipeline mit der Gesamtauflösung der segmentierten Anzeige bereit, die den eingehenden Datenstrom über ein Kommunikationsnetzwerk an die Knoten eines Visualisierungsclusters überträgt. Jeder Knoten des Clusters rendert einen Ausschnitt des Gesamtbildes und bringt diesen auf dem zugehörigen Segment synchronisiert zur Anzeige. Die interne Verarbeitung der von der Applikation generierten OpenGL-Datenströme unterscheidet sich jedoch grundlegend von der existierenden Lösung. Während die Tilesort-SPU von Chromium die Daten entsprechend der Segmentierung der Anzeige sortiert und sequenziell an die relevanten Knoten versendet, überträgt die in der Arbeit vorgestellte Schnittstelle die Graphikbefehle simultan. Die dadurch erreichte Vermeidung redundanter Übertragungen bewirkt bereits einen besseren Durchsatz der Kommunikationskanäle und zusätzlich eine signifikante Verringerung der Prozessorbelastung des Applikationsrechners. Die freie gewordene Kapazität schafft wiederum die Voraussetzung für die Anwendung verschiedener Optimierungsverfahren zur weiteren Steigerung der graphischen Gesamtleistung der parallelen Schnittstelle. Dazu zählt neben der Zwischenspeicherung von Datensequenzen in einem Stream Cache die Filterung der OpenGL-Kommandoströme mit graphischen Culling-Verfahren. Speziell zum aktiv-stereoskopischen Rendern auf dem an der Professur vorhandenen zylindrischen Projektionssystem enthält die Schnittstelle Anpassungen für die Synchronisationshardware und die bildbasierte Korrektur der Parallaxe.

Für die schnelle Visualisierung großer Modelle werden sogenannte Echtzeit-Visualisierungsverfahren (real time rendering techniques) eingesetzt. Durch parallele Verarbeitung der Objektdaten auf Multicore-CPUs ist es möglich, die Geschwindigkeit der Darstellung gegenüber GPU-basierten Verfahren weiter zu erhöhen. Insbesondere wurde die Möglichkeit untersucht, das Occlusion-Culling mit Hilfe der CPU durchzuführen. Dabei konnte speziell das Worst-Case-Verhalten verbessert werden. Mit der Anzahl der Systemkomponenten (z.B. Trackingsystem, Beamer, Rechner) steigt die Trägheit (Latenz) des Gesamtsystems, was eine Echtzeitverarbeitung der Daten deutlich erschwert. Durch Bewegungsvorhersagen, die speziell an das Nutzerverhalten im Rahmen der Anwendung angepasst sind, können auftretende Latenzen kompensiert werden. Die Entwicklungen erfolgten im Kontext einer immersiven Tischtennissimulation. Tischtennis gehört zu den schnellsten Sportarten und repräsentiert somit eine anspruchsvolle Umgebung. Ein weiterer wichtiger Aspekt bei der Interaktion mit virtuellen Umgebungen ist die Natürlichkeit (Intuitivität) der Benutzeroberfläche. Durch eine möglichst direkte (aus der Realität bekannte) Umsetzung der Benutzerbewegungen in Systembefehle wird eine höchstmögliche Effektivität im Umgang mit dem System erzielt. Im Rahmen einer Designanwendung wurden Interaktionstechniken realisiert, die den alltäglichen Bewegungsabläufen nachempfunden sind.

The purpose of this thesis is the development of an interactive computer-generated rendering system that provides artists with the ability to create abstract paintings simply and intuitively. This system allows the user to distort a computer-generated environment using image manipulation techniques that are derived from fundamentals of expressionistic art. The primary method by which these images will be abstracted stems from the idea of several small images assembled into a collage that represents multiple viewing points rendered simultaneously. This idea has its roots in the multiple-perspective and collage techniques used by many cubist and futurist artists of the early twentieth century.