Scalable wavelet-based coding of irregular meshes with interactive region-of-interest support

This paper proposes a novel functionality in wavelet-based irregular mesh coding, which is interactive region-of-interest (ROI) support. The proposed approach enables the user to define the arbitrary ROIs at the decoder side and to prioritize and decode these regions at arbitrarily high-granularity levels. In this context, a novel adaptive wavelet transform for irregular meshes is proposed, which enables: 1) varying the resolution across the surface at arbitrarily fine-granularity levels and 2) dynamic tiling, which adapts the tile sizes to the local sampling densities at each resolution level. The proposed tiling approach enables a rate-distortion-optimal distribution of rate across spatial regions. When limiting the highest resolution ROI to the visible regions, the fine granularity of the proposed adaptive wavelet transform reduces the required amount of graphics memory by up to 50%. Furthermore, the required graphics memory for an arbitrary small ROI becomes negligible compared to rendering without ROI support, independent of any tiling decisions. Random access is provided by a novel dynamic tiling approach, which proves to be particularly beneficial for large models of over 10(6) similar to 10(7) vertices. The experiments show that the dynamic tiling introduces a limited lossless rate penalty compared to an equivalent codec without ROI support. Additionally, rate savings up to 85% are observed while decoding ROIs of tens of thousands of vertices

Setting intelligent city tiling strategies for urban shading simulations

Assessing accurately the solar potential of all building surfaces in cities, including shading and multiple reflections between buildings, is essential for urban energy modelling. However, since the number of surface interactions and radiation exchanges increase exponentially with the scale of the district, innovative computational strategies are needed, some of which will be introduced in the present work. They should hold the best compromise between result accuracy and computational efficiency, i.e. computational time and memory requirements. In this study, different approaches that may be used for the computation of urban solar irradiance in large areas are presented. Two concrete urban case studies of different densities have been used to compare and evaluate three different methods: the Perez Sky model, the Simplified Radiosity Algorithm and a new scene tiling method implemented in our urban simulation platform SimStadt, used for feasible estimations on a large scale. To quantify the influence of shading, the new concept of Urban Shading Ratio has been introduced and used for this evaluation process. In high density urban areas, this index may reach 60% for facades and 25% for roofs. Tiles of 500 m width and 200 m overlap are a minimum requirement in this case to compute solar irradiance with an acceptable accuracy. In medium density areas, tiles of 300 m width and 100 m overlap meet perfectly the accuracy requirements. In addition, the solar potential for various solar energy thresholds as well as the monthly variation of the Urban Shading Ratio have been quantified for both case studies, distinguishing between roofs and facades of different orientations

Methods for Procedural Terrain Generation

Procedural generation has been utilized in the automatic generation of data for a long time. This automated processing has been utilized in the entertainment industry as well as in research work in order to be able to quickly produce large amounts of just the kind of data needed, for example, in system testing. In this thesis, we examine different ways to utilize procedural generation to produce different synthetic terrains. First, we will take a closer look at what procedural generation is, where it originally started, and where it was utilized. From this we move on to look at how this technology is utilized in the creation of terrains and what terrain is generally visually required. From this we move on to look at different ways to implement terrain generation. As part of this thesis, we have selected three methods and implemented our own implementations for terrain generation. We look at the performance of these implementations, and what a test group thinks about those synthetic terrains. The results obtained from this are analyzed and presented at the end of the thesis.Proseduraalista generointia on hyödynnetty datan automaattisessa tuottamisessa jo pitkään. Tätä automatisoitua prosessointia on niin hyödynnetty viihdeteollisuudessa kuin tutkimustyössä, jotta ollaan voitu tuottaa nopeasti suuria määriä juuri sellaista dataa kuin tarvitaan esimerkiksi järjestelmän testauksessa. Tässä tutkielmassa tarkastellaan erilaisia tapoja hyödyntää proseduraalista generointia erilaisten synteettisten maastojen tuottamiseksi. Aluksi tutustutaan hieman tarkemmin siihen mitä proseduraalinen generointi on, mistä se on alunperin lähtenyt ja mihin sitä on hyödynnetty. Tästä siirrytään tarkastelemaan miten kyseistä tekniikkaa hyödynnetään maastojen luomisessa ja mitä maastoilta yleensä visuaalisesti vaaditaan. Tästä siirrytään tarkastelemaan eri tapoja toteuttaa maaston generointia. Osana tätä tutkielmaa, on valittu kolme menetelmää ja laadittu niistä kullekin oma toteutus maaston generointiin. Työssä tarkastellaan näiden toteutusten suoritustuloksia, ja mitä mieltä testiryhmä on kyseisistä synteettisistä maastoista. Saadut tulokset ja niiden analyyysi esitellään tutkielman lopussa

Modular technology: a methodology for the creation of virtual environments in terrain driving simulators

This paper presents the latest research and developments in Modular Technology, a constructive methodology designed to create the environments of the virtual driving simulators of CITEF. Modular Technology discretizes the scene into a finite number of modules or portions of the environment, which after being instantiated and subjected to a series of geometric transformations using shaders, are meticulously assembled to reproduce the virtual scene. This tiling system has a set of particularities that make it different from the rest of tiling systems used up to now. These particularities are designed to get the maximum benefit of these type of virtual representations and can be summarized in four points: the shape of the module; the way in which the family is defined; the positioning system of these modules; and the deformation of these modules using shaders. In this way a substantial reduction in the number of geographical entities in the environment can be attained and an increase in the diversity and flexibility of the environment. There are many advantages to be had from this form of generation: savings in scene size, loading times and resource requirements, greater flexibility and clarity of the scene graph and a more substantial upgrade capacity of the nvironment. has a set of particularities that make it different from the rest of tiling systems used up to now. These particularities are designed to get the maximum benefit of these type of virtual representations and can be summarized in four points: the shape of the module; the way in which the family is defined; the positioning system of these modules; and the deformation of these modules using shaders. In this way a substantial reduction in the number of geographical entities in the environment can be attained and an increase in the diversity and flexibility of the environment. There are many advantages to be had from this form of generation: savings in scene size, loading times and resource requirements, greater flexibility and clarity of the scene graph and a more substantial upgrade capacity of the environment

Data Presentation and Visualization (DPV) Interface Control Document

Data Presentation and Visualization (DPV) is a subset of the modeling and simulation (M&S) capabilities at Kennedy Space Center (KSC) that endeavors to address the challenges of how to present and share simulation output for analysts, stakeholders, decision makers, and other interested parties. DPV activities focus on the development and provision of visualization tools to meet the objectives identified above, as well as providing supporting tools and capabilities required to make its visualization products available and accessible across NASA

The Walkthrough Aplication in Large 3D Terrain

V oblasti počítačové grafiky se často setkáváme s vykreslováním velmi rozsáhlé krajiny. I přes výkony dnešních počítačů se jedná o velmi náročné výpočty. Jsou proto vyvíjeny algoritmy, které snižují úroveň detailu a vykreslují jen tu část krajiny, jenž je pro pozorovatele viditelná. Tato práce se zabývá popisem jednoho z těchto algoritmů a jeho různými modifikacemi. Součástí problému je také samotné vytváření hierarchie dlaždic krajiny, se kterou by mohl daný algoritmus pracovat. Výsledkem práce je potom implementace daného problému v knihovně OpenSceneGraph.Rendering of large terrain is common problem in 3D computer graphics. Even if we have high-tech hardware equipment today, there is still a lot of high computational demand. Therefore new algorithms are developed. These algorithms include level of detail rendering and culling objects in dependence on view of camera. This bachelor thesis describes one of these algorithms and its modifications. Part of the problem is also creation of tiles hierarchy for these algorithms. Result of the thesis is application implemented in OpenSceneGraph.

Procedural City Generation with Combined Architectures for Real-time Visualization

The work and research of this paper sought to build upon traditional city generation and simulation in creating a tool that both realistically simulates cities and their prominent features and also creates aesthetic and artistically rich cities using assets that combine several contemporary or near contemporary architectural styles. The major city features simulated are the surrounding terrain, road networks, individual buildings, and building placement. The tools used to both create and integrate these features were created in Houdini with Unreal Engine 5 as the intended final destination. This research was influenced by the city, town, and road networking of Ghost Recon:Wildlands. Both games exhibit successful creation and integration of cities in a real-time open world that creates a holistic and visually compelling experience. The software used in the development of this project were Houdini, Maya, Unreal Engine 5, and Zbrush, as well as Adobe Substance Designer, Substance Painter, and Photoshop. The city generation tool was built with the intent that it would be flexible. In this context flexibility refers to the capability to create many different kinds of city regions based on user specifications. Region size, road density and connectivity, and building types are examples of qualities of the city that can be directly controlled. The tool currently uses one set of city assets created with intent for use together and an overall design cohesion but is also built flexibly enough that new building assets could be included, only requiring the addition of building generators for the new set. Alternatively, assets developed with the current generation methods in mind could also be used to change the visual style of the city. Buildings were both generated and placed based on a district classification. Buildings were established as small residential, large residential, religious buildings, and government/commercial before being placed in appropriate locations in the city based on user district specifications

Application of modeling and texturing techniques for game ready levels

Treball final de Grau en Disseny i Desenvolupament de Videojocs. Codi: VJ1241. Curs acadèmic: 2020/2021This document establishes and summarizes the creation of a game level focusing on 3D art and optimization techniques. This project explores the development of a demo level that, ideally, could be in a game. It will explore modeling and texturing techniques that improve the reusability of the 3D models and employ diverse methods to optimize the final result. Another crucial point is the application of methods that bolster up the level of detail in the scene and break the repeatability