Hur människor uppfattar rumsligheter är komplext. Människor baserar det upplevda rummet på professionell expertis, erfarenheter och vilket visuellt kommunikationsverktyg som rummet presenteras med hjälp av. Studiens syfte är att undersöka hur den visuella kommunikationen mellan arkitekter och kunder ser ut, hur arkitekter och kunder uppfattar rumsligheter, hur uppfattningen skiljer sig åt och om kommunikationen däremellan kan underlättas med hjälp av realtidsvisualisering (VR). Dessutom undersöker examensarbetet hur en sådan visuell kommunikation skulle kunna gå till och hur detaljerad en VR-modell behöver vara. Spelmotorn Unity och VR-plattformen HTC Vive används för att producera och driva interaktiva VR-modeller. Studien undersöker hur dessa kan användas som ett visuellt kommunikationsverktyg mellan arkitekter och kunder för att utveckla kommunikationen dem emellan. Litteraturen visar på tydlig klyfta i kommunikationen mellan arkitekt och kund där information går förlorad. Genom användandet av realtidsvisualisering hävdas det att kommunikationen kan underlättas och en ökad förståelse av rymd och skala uppnås. I studien testas tre VR-modeller med tre olika detaljnivåer på respondenter, tre arkitekter och två kunder. Efter testet intervjuas personerna om deras erfarenheter och rumsliga upplevelse för de olika modellerna. Intervjuerna pekar på att den skillnad i rumsuppfattning som finns mellan arkitekt och kund kan överbryggas med hjälp av VR som kan konkretisera arkitektur och medför att alla kan förstå rumsligheter på sina egna villkor. Undersökningen visar att VR är ett användbart visuellt kommunikationsverktyg. Inte bara som barriärbrytande mellan arkitekt och kund utan även som en integrerad del av den iterativa designprocessen. / How people perceive space is a complex thing. People base the perceived space on professional expertise, experiences and what visual communication tools the room is presented with. The purpose of the study is to investigate the visual communication between architects and clients; how architects and clients perceive spatial characteristics and how the perception differs and whether communication between them can be made easier using real-time visualization (VR). In addition, the study investigates how such communication could go and how detailed a VR model needs to be. The game engine Unity and VR-platform HTC Vive are used to produce interactive VR models and investigate how these can be used as a visual communication tool between architects and clients to improve the communication between them. The literature shows a clear gap in the communication between architects and clients where information is lost. Using real-time visualization, the communication can be eased, and an increased understanding of space and scale achieved. In the study, three VR models are tested with three various levels of detail on respondents, three architects and two customers. After the test, the respondents are interviewed about their experiences and space perception of the different models. The interviews show that the difference in space perception between architect and client can be overcome using VR that can show architecture and allow everyone to understand spatiality on their own terms. The investigation shows that VR as a visual communication tool is useful. Not only as barrier-breaking between architects and clients, but also as an integral part of the iterative design process.

nÃo hà / Ambientes providos de multidÃes sÃo empregados em diversas aplicaÃÃes, como jogos, simuladores e editores. Muitas destas aplicaÃÃes nÃo requerem somente a renderizaÃÃo de agentes animados de forma realÃstica e detalhada, mas que seja executada suavemente em tempo real, tarefa que facilmente esgota os recursos do sistema (mesmo considerando hardware no estado da arte). Por conta disso,a renderizaÃÃo de multidÃes em tempo real permanece como um desafio dentro da computaÃÃo grÃfica. Abordagens explorando nÃvel de detalhe, descarte por visibilidade e renderizaÃÃo baseada em imagens foram propostas no intuito de viabilizar esta tarefa. As duas primeiras aumentam a eficiÃncia da renderizaÃÃo, mas as vezes nÃo sÃo suficientes para manter taxas de quadros por segundo interativas. Grande parte dos estudos acerca do tema se concentra em tÃcnicas de renderizaÃÃo baseadas em imagem, especificamente com o emprego de impostores. Neste trabalho à proposto um mÃtodo que faz o balanÃo da demanda computacional da renderizaÃÃo atravÃs da variaÃÃo da distÃncia do limiar onde ocorre a troca de representaÃÃo entre os modelos de geometria completa (malhas) e os baseados em imagem (impostores) de acordo com os recursos disponÃveis. / Environments populated with crowds are employed in various applications, such as games, simulators and editors. Many of these environments require not only a realistic and detailed rendering, but it must run smoothly in real-time. This task easily exhausts the systemâs resources, even considering the current state-of-the-art hardware. Therefore, crowd rendering in real-time remains a challenge in computer graphics. Approaches exploiting levels of detail, visibility culling and image-based rendering are presented in order to facilitate this task. The first two increase the efficiency of rendering, but sometimes are not enough to keep an interactive frame rate. Some researches on this subject focus on image-based rendering techniques, specifically with the use of impostors. In this work it is proposed a method that balances the computational demand of rendering job by varying the thresholdâs distance of the representation switch between full geometry (mesh) and image-based(impostors) models in accordance with the available resources.

To be able to run a flight simulator a large area of terrain needs to be visualized. The simulator must update the screen in real-time to make the simulation work well. One way of managing large terrains is to tile the area into quadratic tiles to be able to work with different detailed representations of the terrain at different distances from the user. The tiles need to match with the adjacent tiles in the edge points to avoid cracks. When every tile can have a number of different levels of detail this means that the different levels of detail need to match too. This was previously done by having the same edge points in all levels of detail, giving an unnicessarily large polygon count in the less detailed levels. the method developed in this report uses different versions of borders with their own level of detail, adapting to different detail levels at the adjacent tile, reducing hte number of polygons.

Au cours des deux dernières décennies, les applications temps réel ont montré des améliorations colossales dans la génération de rendus photoréalistes. Cela est principalement dû à la disponibilité de modèles 3D avec une quantité croissante de détails. L'approche traditionnelle pour représenter et visualiser des objets 3D hautement détaillés est de les décomposer en un maillage basse fréquence et une carte de déplacement encodant les détails. La tessellation matérielle est le support idéal pour implémenter un rendu efficace de cette représentation. Dans ce contexte, nous proposons une méthode générale pour la génération et le rendu de maillages multi-résolutions compatibles avec la tessellation matérielle. Tout d'abord, nous introduisons une métrique dépendant de la vue capturant à la fois les distorsions géométriques et paramétriques, permettant de sélectionner la le niveau de résolution approprié au moment du rendu. Deuxièmement, nous présentons une nouvelle représentation hiérarchique permettant d'une part des transitions temporelles et spatiales continues entre les niveaux et d'autre part une tessellation matérielle non uniforme. Enfin, nous élaborons un processus de simplification pour générer notre représentation hiérarchique tout en minimisant notre métrique d'erreur. Notre méthode conduit à d'énormes améliorations tant en termes du nombre de triangles affiché qu'en temps de rendu par rapport aux méthodes alternatives. / In the last two decades, real-time applications have exhibited colossal improvements in the generation of photo-realistic images. This is mainly due to the availability of 3D models with an increasing amount of details. Currently, the traditional approach to represent and visualize highly detailed 3D objects is to decompose them into a low-frequency mesh and a displacement map encoding the details. The hardware tessellation is the ideal support to implement an efficient rendering of this representation. In this context, we propose a general framework for the generation and the rendering of multi-resolution feature-aware meshes compatible with hardware tessellation. First, we introduce a view-dependent metric capturing both geometric and parametric distortions, allowing to select the appropriate resolution at rendertime. Second, we present a novel hierarchical representation enabling on the one hand smooth temporal and spatial transitions between levels and on the other hand a non-uniform hardware tessellation. Last, we devise a simplification process to generate our hierarchical representation while minimizing our error metric. Our framework leads to huge improvements both in terms of triangle count and rendering time in comparison to alternative methods.

This thesis discusses implementation of LoD terrain visualization algorithm Seamless Patches for GPU-Based Terrain Rendering as extension for Coin3D library. It presents procedures which this algorithm uses for displaying large terrain datasets. Entire terrain is composed of patches that are stored in patch hierarchy. Patch hierarchy is traversed during runtime to generate active patches based on observer's position. Each patch consists of predefined tiles and connection strips so it doesn't need to store any geometry. During render of tiles and strips, displacement shader is applied. This thesis also evaluates results achieved in sample application and suggests some modifications to further increase algorithm performance.

This work is focusing on optimization of large scale terrain rendering. It explains basic methods and data structures for optimization. It describes fundamentals of methods such as ROAM, Geometrical clipmaps, GPU Based Geometrical Clipmaps, GeoMipMapping and Chunked LOD. It explains implementation details of system for terrain optimization based on GeoMipMapping method.

No description available.

One way of increasing 3D rendering performance is the use of foveated rendering. In this thesis a novel foveated rendering technique called gaze contingent depth of field tessellation (GC DOF tessellation) is proposed. Tessellation is the process of subdividing geometry to increase detail. The technique works by applying tessellation to all objects within the focal plane, gradually decreasing tessellation levels as applied blur increases. As the user moves their gaze the focal plane shifts and objects go from blurry to sharp at the same time as the fidelity of the object increases. This can help hide the pops that occur as objects change shape. The technique was evaluated in a user study with 32 participants. For the evaluated scene the technique helped reduce the number of primitives rendered by around 70 % and frame time by around 9 % compared to using full adaptive tessellation. The user study showed that as the level of blur increased the detection rate for pops decreased, suggesting that the technique could be used to hide pops that occur due to tessellation. However, further research is needed to solidify these findings. / Ett sätt att öka renderingsprestanda i 3D applikationer är att använda foveated rendering. I denna uppsats presenteras en ny foveated rendering-teknik som kallas gaze contingent depth of field tessellering (GC DOF tessellering). Tessellering är när geometri delas i mindre delar för att öka detaljrikedom. Tekniken fungerar genom att applicera tessellering på alla objekt i fokalplanet och gradvis minska tesselleringsnivåer när oskärpan ökar. När användaren flyttar sin blick så flyttas fokalplanet och suddiga objekt blir skarpa samtidigt som detaljrikedomen i objektet ökar. Det kan hjälpa till att dölja de ’pops’ som uppstår när objekt ändrar form. Tekniken utvärderades i en användarstudie med 32 del- tagare. I den utvärderade scenen visade sig tekniken minska antalet renderade primitiver med ca 70 % och minska renderingstiden med ca 9 % jämfört med att använda full adaptiv tessellering. Användarstudien visade att när oskärpa ökade så minskade antalet som sa sig se ’pops’, vilket tyder på att tekniken kan användas för att dölja de ’pops’ som uppstår på grund av tessellering. Det behövs dock ytterligare forskning för att säkerställa dessa fynd.

No description available.

I arbetet studerades vad som kan orsaka hög detaljeringsgrad i detaljplaner. Samt vilka konsekvenser som hög detaljeringsgrad kan resultera i. Litteraturstudien visade att hög detaljeringsgrad sannolikt inte berodde enbart på lagstiftning, utan även på mänskligt beteende och vanor. Därför nyttjades teorin Institutional theory för att bidra med en ram och skapa förståelse för hur och varför det ser ut som det gör och hur detaljplanerna har blivit som de är idag. Utöver det användes även fjärilseffekten och kaosteorin för att bidra med en förståelse för det alternativa amplifierande av effekter och hur sammanlagda små handlingar och effekter kan resultera i konsekvenser. Studien utfördes genom en djupdykande litteraturstudie och 9 semi-strukturerade intervjuer från ett brett utbud av respondenter från såväl den offentliga som privata sidan. På grund av det kunde en helhetsbild skapas av situationen och inte enbart en synvinkel på marknaden. Eftersom ämnet är något postmodernistiskt fick respondenterna frågor som stimulerade diskussion med dem själva och de kunde därför komma med förklaringar, förslag och insikter. För att kunna tolka materialet från intervjuerna och exkludera partiskhet och irrationella tankar så kategoriserades respondenterna och deras svar analyserades efter vardera gruppering. Initialt identifierades de alternativa orsakerna bakom hög detaljeringsgrad och de utvärderades därefter med hjälp av en modell över hur vi människor fungerar och arbetar enligt Institutional theory. Varav det visade sig att det framstår mycket sannolikt att detaljplanen ser ut som den gör idag på grund av kulturella normer, beteendemönster med mera. Vilket i det här fallet fokuserades mest på hur detaljplanerna generellt påverkas och inte hur lagstiftningen har påverkats. Alternativa konsekvenser och effekter identifierades därefter genom respondenternas alternativa fördelar och nackdelar med situationen. Dessa effekter analyserades efter vilka effekter de kan resultera i vad gäller exempelvis tid, kostnader samt påverkan på sociala och ekologiska faktorer. Därefter kunde dessa fyllas i en modell av fjärilseffekten för att bidra med en visuell översikt över situationen.  Baserat på modellen framstår det kunna innebära större konsekvenser om detaljplaner har hög detaljeringsgrad i stor utsträckning. Enligt modellen kan det exempelvis potentiellt ha en påverkan på byggtakten. Varav om så är fallet, så kan det även ha en påverkan på landets ekonomiska tillväxt. / In this work it was studied what can cause a high level of detail in detailed plans. As well as what consequences a high level of detail can result in.The literature study showed that a high level of detail probably was due not only to legislation, but also to human behavior and habits. Therefore, the Institutional theory was used to contribute with a framework and create an understanding of how and why it is the way it is and how the detailed plans have become what they are today.In addition, the butterfly effect and chaos theory were also used to contribute with an understanding of the alternative amplification of effects and how small actions and effects combined can result in consequences.The study was conducted through an in-depth literature study and 9 semi-structured interviews from a wide range of respondents from both the public and private sectors. Due to this, an overall picture could be created of the situation and not just a single point of view from the market. Since the subject is somewhat postmodern, the respondents were asked questions that stimulated discussion with themselves and they could therefore provide explanations, suggestions and insights.In order to be able to interpret the material from the interviews and exclude bias and irrational thoughts, the respondents were categorized and their answers were analyzed according to each grouping. Initially, the alternative causes behind a high level of detail were identified and they were then evaluated using a model of how us humans function and work according to institutional theory. From which it turned out that it seems very likely that the detailed plan is what it is today due to cultural norms, behavioral patterns and more. Which in this case was mostly focused on how the detailed plans are generally affected, and not how the legislation has been affected. Alternative consequences and effects were then identified through the respondents' alternative advantages and disadvantages of the situation. These effects were analyzed according to the effects they can result in in terms of, for example, time, costs and the impact on social and ecological factors. Then these could be inserted into a model of the butterfly effect to contribute with a visual overview of the situation. Based on the model, it appears that this could have major consequences if detailed plans have a high level of detail to a great extent. According to the model for example, it can potentially have an impact on the rate of construction. Of which if this is the case, it can also have an impact on the country's economic growth.