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Translucent materials exist all around us. They can be commonly found in materials such as marble, jade and fluids such as milk. Subsurface scattering describes one of the most complex yet beautiful effects of light in translucent materials. However, this light and media interaction is difficult to simulate. Although Monte Carlo approaches can simulate these effects, they are computationally expensive. Further complexities in simulation occur, when indirect illumination from translucent materials are considered, as they scatter light and illuminate other surfaces. In addition, when translucent materials are illuminated by area lights, fast techniques such as voxel based methods have difficulties in estimating direct visibility. In my research, I aim to develop efficient techniques for rendering homogeneous translucent materials under area light illumination at interactive speed. In the first research of this thesis, I present a real-time approximation technique for subsurface scattering rendering that uses two separate voxel structures for rendering single scattering and multiple scattering effects. In my algorithm, a ray marching approach is used to traverse rays from the light source through the voxel structure, the Enhanced Subsurface Light Propagation Volumes (ESLPV), while leaving its radiance compressed into spherical harmonics in each marching step. During rendering, we use importance sampling to select important samples along the refracted ray. Some propagation optimization routines are used to remove unnecessary computations in the propagation iterations of Light Propagation Volumes (LPV) based algorithms and also accelerate the rendering time while maintaining the same visual quality. As the LPV is not a physically accurate algorithm, flux can be lost unnecessarily for each simulation step. I proposed a multi-resolution voxel structure to reduce the flux lost due to the numerous scattering events simulated in high resolution voxels and also preserve the radiance for backlighting at similar quality to the Photon Based Diffusion methods. In the second research, I proposed a deferred multi-resolution approach for rendering direct illumination effects such as soft shadows when translucent and other opaque objects are illuminated by area lights. My approach subdivides the screenspace into multiresolution 2D-fragments in which higher resolution fragments are created to represent geometric and depth discontinuities as well as shadow boundaries. I proposed a sub-fragment visibility test scheme that focuses on discontinuities within a fragment. A gradient aware subdivision scheme is developed to refine the discontinuities according to its gradients. My technique utilizes the stream-compaction feature of the transform feedback shader (TFS) in the graphics shading pipeline to filter out fragments for soft shadow refinement easily. A single pass screenspace irradiance upsampling scheme which uses radial basis functions (RBF) and an adaptive variance scaling factor is propose for interpolating scattered fragments. This reduces artifacts caused by large fragments while also significantly reducing the number of visibility rays that we require. In my final research, I combine the work of my first two researches and tackle two separate illumination problems for area lighting. First, the focus is on the appearance of translucent materials under illumination from area lights, which also casts soft shadows on underlying surfaces. Next, the translucent materials distribute this scattered lighting towards its surrounding surfaces. Next, we focus on the appearance of indirect illumination on the surrounding scene after receiving scattered light from translucent materials. To solve both direct and indirect illumination problems, we use a set of Poisson disk distributed samples on translucent objects and scene to gather illumination from area lights. The gathered illuminations are ’injected’ as transmitted flux into the ESLPV to render the translucent objects. For simulating indirect illumination, the reflected flux are injected into the LPV and distributed. The multi-resolution approach employed in this thesis provides accelerated rendering which can be used in various multimedia applications (e.g. games that require translucent object rendering or soft shadow rendering), and visual arts (e.g. pre-renders for rendering programs). Doctor of Philosophy

We present a robust, unbiased technique for intelligent light-path construction in path-tracing algorithms. Inspired by existing path-guiding algorithms, our method learns an approximate representation of the scene's spatio-directional radiance field in an unbiased and iterative manner. To that end, we propose an adaptive spatio-directional hybrid data structure, referred to as SD-tree, for storing and sampling incident radiance. The SD-tree consists of an upper part-a binary tree that partitions the 3D spatial domain of the light field-and a lower part-a quadtree that partitions the 2D directional domain. We further present a principled way to automatically budget training and rendering computations to minimize the variance of the final image. Our method does not require tuning hyperparameters, although we allow limiting the memory footprint of the SD-tree. The aforementioned properties, its ease of implementation, and its stable performance make our method compatible with production environments. We demonstrate the merits of our method on scenes with difficult visibility, detailed geometry, and complex specular-glossy light transport, achieving better performance than previous state-of-the-art algorithms.

Visual computing has become highly attractive for boosting research endeavors in the materials science domain. Using visual computing, a multitude of different phenomena may now be studied, at various scales, dimensions, or using different modalities. This was simply impossible before. Visual computing techniques provide novel insights in order to understand complex material systems of interest, which is demonstrated by strongly rising number of new approaches, publishing new techniques for materials analysis and simulation.

This work was partially funded by TIN2014-52211-C2-2R project from Ministerio de Economia y Competitividad (Spain) and by the ANR under ref. ANR-16-CE33-0001 (France)

Kljub tehnološkemu napredku zadnjih stoletij in desetletij se še vedno soočamo s problematiko prikaza in upodobitve barve v različnih medijih in ohranjanja zaznave barve. Ena od možnosti, za katero se lahko odločimo pri zagotavljanju stalne barvne zaznave, so modeli barvnega zaznavanja. Trenutno je aktualen CIECAM02, ki se še vedno ne uporablja v 3D računalniški grafi ki, s katero se vsak dan srečujemo. Namen raziskave je bil pregled barvnih prostorov v 3D računalniški grafiki, pregled reprodukcije barv in materialov, algoritmov za senčenje ter izbranih sodobnih tehnologij upodabljanja za doseganje korektne končne vizualizacije. V nadaljevanju smo želeli proučiti model barvnega zaznavanja CIECAM02 do te mere, da bi ga lahko uporabili v povezavi s 3D računalniško grafiko. V ta namen smo v programu Blender postavili testno sceno in jo upodobili s tremi upodobljevalniki: Blender Render in Cycles, ki sta že vgrajena, in z dodatkom Yafaray. Izkazalo se je, da CIECAM02 lahko uporabimo tudi v 3D prostoru in da z njegovo uporabo dobimo boljše rezultate ujemanja barv pri spremembi ozadja. Poleg tega smo ugotovili, da barv ne upodabljajo vsi upodobljevalniki enako. Omenjena raziskava je aktualna za vse, ki želijo svoje dvo- ali tridimezionalne izdelke predstaviti s pomočjo 3D računalniške grafike, torej tudi za področje vizualizacij oblačil in tekstilnih izdelkov, ki se uporabljajo pri modnem oblikovanju in oblikovanju interjerjev, avtomobilski, navtični in letalski industriji ter tudi širše, kjer so dovršene 3D vizualizacije tekstilij in oblačil nepogrešljivi element vizualnih in grafičnih komunikacij.

Selective visual attention is an amazing capability of primate visual system to restrict the focus to few interesting objects (or portions) in a scene. Thus, primates are able to pay attention to the required visual content amidst myriads of other visual information. It enables them to interact with the external environment in real time through reduction of computational load in their brain. This inspires image and computer vision scientists to derive computational models of visual attention and to use them in varieties of applications in real-life, mainly to speed up the processing through reduction of computational burden which often characterizes image processing and vision tasks. This chapter discusses a wide variety of such applications of visual attention models in image processing, computer vision and graphics.

The title of this three-volume set on graphics from Romania, ‘Graphics without Computers’, makes a strong statement. It attracts attention, but, in its ambiguity, is misleading for two reasons. Fir...

This article describes a simple course exercise to deepen the understanding of real-time shadow volume algorithms. The exercise takes less than 10 minutes to perform during lecture time, leads to a profounder understanding of the topic, and serves as a basis for further discussions of improvements for the shadow mapping algorithm. Using this exercise, the authors noticed an increase in students implementing shadow algorithms for later real-time graphics projects.

These days computer graphics technology has been applied in diverse IT fields. Needs for computer graphics such as 3D Printer, Head Mount Display, VR & AR are growing rapidly. Computer graphics will be more specialized and demanding for graphics specialists will be also increased. However, serious mathematical background obstructs people to learning computer graphics. An efficient computer graphics learning system would be helpful for graphics experts training. By analyzing the graphics theory, we propose an educational software system with that students can effectively learn computer graphics. Our system focuses on theoretical objects of computer graphics and enhances accessibility and intuition using web and blocks.

This article describes a simple course exercise to deepen the understanding of real-time shadow mapping algorithms. The exercise takes less than 10 minutes to perform during lecture time, leads to a profounder understanding of the topic, and serves as a basis for further discussions of improvements for the shadow mapping algorithm. Using this exercise, the authors noticed an increase in implementing shadow algorithms for later real-time graphics projects.

In today's society rapid development of science and technology, the computer figure image design can be widely used in various industries. In the film and television, advertising, exhibition, art, electronic play in areas such as lack of necessary computer graphics design. With the development of computer information technology, the design of the graphics technology will progress. On the technology no longer content with a simple graphics rendering, more note focus on visual sense of the data, enhance the figure shape the image of beauty and expression. This paper mainly discusses the computer graphics design and visual communication design in today's society rapid development of science and technology, computer graphics design has also been extensively applied to various industries. In the film and television, advertising, exhibition, art, video games, and other fields are short of necessary computer graphics design. With the development of information technology, computing machine graphics design technology progress. Current technology is no longer satisfied with the image of a simple now, pay more attention to the visual sensation of biography and enhance the figure shape the image of aesthetic feeling and expression. This paper mainly discusses the computer graphics design and research of visual communication design.

In Chapter 3, I talked about many of the features that you have when working with text. Believe me, Chapter 3 only touches the surface of all of the things that you can do with text in InDesign. However, after reading through Chapter 3 you should have a foundation for setting type in InDesign.

With the development of calculation ability and data processing ability of computer,so process complex data has become possible,with computer graphics methods, in a easily observe graphic way to represent data requirements has became popular day by day. The article describes some fields which attract users' attention,such as scientific processing, landscape simulation,visualization research technique in medical diagnosis.

Uberblick und Entwicklung ,,Intelligent Graphics is about visually representing the world and visually representing our ideas. Artificial intelligence is about symbolically representing the world, and symbolically representing our ideas. And between the visual and the symbolic, between the concrete and the abstract, there should be no boundary.“Henry Lieberman [1] Liebermans Zitat beschreibt ein informatisches Paradigma, dessen zentrale Idee auf der Verknupfung von Verfahren der Kunstlichen Intelligenz (KI) mit denen der Computergrafik (CG) beruht: Das Schlagwort Smart Graphics oder synonym Intelligent Graphics bezeichnet heute unterschiedlichste Anwendungsszenarien.Diese reichen vonder intelligenten und kontextsensitiven Anordnung grafischer Elemente in 2D-Desktopsystemen bis hin zu sprachgestischen Schnittstellen oder intelligenten Agenten in virtuellen Umgebungen als Assistenten der Benutzer. Allen diesen Ansatzen ist gemein, dass eine grafische Mensch-Computer-Schnittstelle mithilfe von KI-Verfahren an die kognitiven Eigenschaften des Benutzers angepasst wird, um die Bedienung zu verbessern. Erste – aus heutiger Sicht bahnbrechende – Beispiele fur die zentrale Idee des Paradigmas sind zwei Projekte aus dem Bereich der KI und speziell der Mensch-Computer-Interaktion (MCI): SHRDLU von TerryWinograd aus dem Jahr 1971 [2] und Bolts Put-That-There aus dem Jahr 1980 [3] (Abb. 1). In vielen fruhen Projekten spielt eine Ankopplung von semantischen Modellen an die computergrafischen Szenen eine primare Rolle. Fur die Interpretation der Benutzerauserungen in SHRDLU und Put-That-There ist dies eine Notwendigkeit. In heutigen Ansatzen kommt dagegen fast das gesamte Spektrum der existierenden KI-Methoden zum Einsatz. Aktuelle Forschungsergebnisse zu diesem Thema finden sich zum einen auf den wissenschaftlichen Tagungen der beteiligten Fachgebiete Computergrafik sowie KI, aber speziell auch auf dediziertenVeranstaltungenwie dem Smart Graphics Symposium (seit 2000), der International Conference on Computer Graphics and Artificial Intelligence – 3IA, (seit 1994) sowie ubergreifend auf denMCI-relevanten Plattformen. Bis zu Beginn der 90er-Jahre ist die Anzeige interaktiver grafischer Szenen eine Domane teurer Spezialgerate. Dann treibt die Verbreitung grafischer Benutzerschnittstellen, insbesondere auch der Erfolg der Computerspiele, die Realisierung interaktiver Grafiken auf Standard-PCs und Heimgeraten voran. Seither steigen Qualitat der mittels gunstiger Consumer-Gerate synthetisierten Inhalte, die Vielfalt der verschiedenen Interaktionsmoglichkeiten sowie ebenfalls die Erwartungshaltung der Verbraucher an die jeweils nachste Generation stetig. Als Resultat steigen Anforderungen und Komplexitat der softwaretechnischen Losungen signifikant. Anhand von aktuellen Anwendungsfallen werden

The article describes a new author's method of floodlighting designing of architectural objects. The method is described and the advantages and limits are shown. The method allows to create a multivariate concept of illumination without the need of usage of complex visualization tools. It is based on projections on the real object of the 3D model or two-dimensional grid, the luminance distribution image. This distribution can be implemented by currently produced lighting equipment, as well as by the modification of this equipment or the new one, not produced yet or being in production phase. The luminance distribution is created by a lighting designer in real time. The image display is realized by system comprising a PC, computer application and a multimedia projector. The luminance distributions modified in application or new created, allow to generate a computer application photometric files. These files are the basis for selection from the lighting equipment base luminaires carrying out luminance distributions similar to the intended ones. It is also possible to design new luminaires, which fulfill required luminance distributions. The result of this method is complete technical documentation of lighting equipment used for the specific lighting solution.

The current development in the area of computer graphics focuses itself on 3D visualization. This direction, set by contemporary trends, further utilizes 3D visualization, increases its quality and improves visualization devices for 3D graphics. This change must be reflected by teaching methods as well, through which future specialists of advanced graphics, modellers, but also programmers and implementation coders. The article presents its own software solution and innovative approach to teaching computer graphics. The solution and all principles are based on the Montessori method of child education.

Over the past decade, development of computer-aided graphics in the field of appliedgraphics is rapid, and the graphics system which is established based on the traditional ruler gauge conditions has also changed dramatically. Therefore, the author reviewed the current situation, following the pulse of the information times, on the premise of practice and application, making bold adjustment to the traditionaldesign graphics teaching of environmental art design major, introducing intelligent 3D modeling technologyin the teaching process, making up for the defect of traditional graphics teaching space expression, and accordingly increase student computer graphics link, in order to construct the teaching system of design graphicswhich is fit to the information times.

Due to the progress of consumer electronics, 3D-Graphics system has become mobilizing and attractive. For 3D graphics gaming applications with high resolution in mobile devices, the cost-effective hardware is crucial and necessary. In order to efficiently render 2D graphics, the raster operation techniques are developed. Traditional anti-aliasing techniques using the grid-based or point-sharing of edge to do super-sampling are not regular and complex. This paper proposed a novel cost-effective strategy for the shared-edge sampling of the primitive in raster operation. No expensive sampling action is involved, and no irregular sampling point is produced in the entire process. Furthermore, the blending colors in the neighborhood of these edges adopt approximate, fast, and robust anti-aliasing according to a set of simple rules.

Foreword to the Special Section on Smart Tools and Applications in Computer Graphics 2015.

In this paper, we conduct theoretical analysis on the novel computer assisted film and the television animation design pattern based on the computer graphics theory and three-dimensional modeling structure optimization. Computer graphics rely on itself, the visualization technology of the data and graphics can be effectively combined, graphic display is a major direction in development of computer graphics. To follow the trend, we analyze the issues from different perspectives. Computer graphics applied to computer animation as success of development of flight simulator prompted the application of computer graphics to television, film and advertising industry.

Now that you can create loops, it is time to move on to learning how to create graphics. This chapter covers

The manipulating technique of lighting is a very important component of realistic image rendering, including lighting model and shading. This paper, first, introduces the basic concepts, the principles and the programming of the general thoughts of Lighting with OpenGL; then, introduces how to compute the light intensity and shading interpolation by investigating the reflex factors on object surface; last, provides a set of cases to show the ideal effect with different rendering techniques.

Computer graphics advances driven by product development became mature in the late 1980s, and advances driven by arts and entertainment matured in the early 2000s. The graphics industry is at an innovation plateau and is ready for the next wave of innovation. This third wave won't be driven in response to a single industry. Rather, innovative researchers will respond to three drivers: the visual representations necessary to handle emerging application disciplines, display and interaction device advances, and graphics systems design and implementation.

In this paper, some basics and advanced rendering methods in computer graphics are introduced. It takes a serious course to understand the principle and details of computergraphics. Here, I try to explain some basics and methods so that engineers and scientists not in the graphics specialty field will be able to understand graphics rendering methods and conceive applications with available means. Copyright © 2010 John Wiley & Sons, Inc. For further resources related to this article, please visit the WIREs website.

Recent progress in modelling, animation and rendering means that rich, high fidelity virtual worlds are found in many interactive graphics applications. However, the viewer’s experience of a 3D world is dependent on the nature of the virtual cinematography, in particular, the camera position, orientation and motion in relation to the elements of the scene and the action. Camera control encompasses viewpoint computation, motion planning and editing. We present a range of computer graphics applications and draw on insights from cinematographic practice in identifying their different requirements with regard to camera control. The nature of the camera control problem varies depending on these requirements, which range from augmented manual control (semi-automatic) in interactive applications, to fully automated approaches. We review the full range of solution techniques from constraint-based to optimization-based approaches, and conclude with an examination of occlusion management and expressiveness in the context of declarative approaches to camera control.

Recently, computer graphics technology has been applied in diverse IT fields such as 3D Printer, virtual/augmented reality as well as traditional applications such as visual effects. However, computer graphics contains robust mathematical/physical knowledge including geometry and optics which are burden for novices to study computer graphics. The paper proposes an effective e-learning platform focused on computer graphics. Our block based method which is implemented using WebGL delivers educational interests and enhanced accessibility.

The interactive rendering of 3D computer graphics has approached the photorealistic quality, as evident by the vivid shading effects and lush outdoor scenes in recent game engines. Clearly, the traditional 3D graphics APIs are reaching their limits, and the need to switch to more extendable ray-tracing based techniques has arisen. In this work, we explore the fundamental differences between ray tracing based and rasterization based techniques, including how they are supported by the processors and by the programming platforms. We duplicate the typical shading effects in both ray tracing and rasterization, starting from the simple Phong lighting, to slightly more complex Whitted-style shadow and reflection. Although the rasterization-based techniques clearly outperform ray tracing in current generations of graphics processors, we show by more precise quantitative analysis that the performance gaps are not as wide as thought. And the gap may narrow further when the requirement of image quality increases in the future.

The benefits of using advanced illumination models in volume visualization have been demonstrated by many researchers. Interactive volume rendering incorporated with advanced lighting has been achieved with GPU acceleration for regular-grid volume data, making volume visualization even more appealing as a tool for 3D data exploration. This paper presents an interactive illumination strategy, which is specially designed and optimized for volume visualization of unstructured-grid data. The basis of the design is a partial differential equation based illumination model to simulate the light propagation, absorption, and scattering within the volumetric medium. In particular, a two-level scheme is introduced to overcome the challenges presented by unstructured grids. Test results show that the added illumination effects such as global shadowing and multiple scattering not only lead to more visually pleasing visualization, but also greatly enhance the perception of the depth information and complex spatial relationships for features of interest in the volume data. This volume visualization enhancement is introduced at a time when unstructured grids are becoming increasingly popular for a variety of scientific simulation applications.

This document introduces a new application for rendering massive LiDAR point cloud data sets of interior environments within highresolution immersive VR display systems. Overall contributions are: to create an application which is able to visualize large-scale point clouds at interactive rates in immersive display environments, to develop a flexible pipeline for processing LiDAR data sets that allows display of both minimally processed and more rigorously processed point clouds, and to provide visualization mechanisms that produce accurate rendering of interior environments to better understand physical aspects of interior spaces. The work introduces three problems with producing accurate immersive rendering of Li-DAR point cloud data sets of interiors and presents solutions to these problems. Rendering performance is compared between the developed application and a previous immersive LiDAR viewer.

Computer graphics application becomes more and more attractive recently as the popularization of the smart phone and computer tablet. It is interested us what we can do through network for making 3DCG models. We have designed and developed an interactive 3DCG Builder system and tried to apply it on internet environment for on-line multi-player. In this paper, we shall provide our design policy and development process.

This chapter introduces some of the 3D graphics capabilities of LibGDX. Along the way, you’ll learn about the concepts and classes necessary to describe and render a three-dimensional scene. You’ll create a simple interactive demo that enables players to control both an object within the scene and the camera viewing the scene. To simplify and streamline this process, you’ll adapt some old classes and write some new classes to accomplish the various tasks involved. Finally, you’ll create a more sophisticated demo based on 2.5D techniques: a game that renders advanced three-dimensional graphics, while the underlying game play is restricted to a two-dimensional plane.

In Chapter 3, you looked at typography, and at how to manipulate text in a text frame. In this chapter, you will be looking at the graphical capabilities of Scribus. You will learn how to manipulate imported pictures, how to work with bitmapped images, and how to work with lines and shapes.

This paper describes a technique for developing an immersive walk-through system that implements a rendering method for superimposing computer graphics onto a panoramic movie in an immersive walk-through system. The system is composed of a locomotion interface and an immersive spherical display. In this study, we analyze the camera path from the movie to stabilize the orientation of the camera for rendering an immersive image. Further, the system superimposes computer graphics (CG) onto the image according to the system coordinates from the movie. We implemented the proposed rendering method to realize a free viewpoint image with the movie and the CG by moving the viewpoint.

As the previous two chapters demonstrate, both statnet and igraph have sophisticated plotting capabilities that can produce a very wide variety of network graphics. However, these plotting functions cannot meet all of the analytic or presentation needs. In particular, network scientists may wish to produce more specialized network graphics. Also, while statnet and igraph excel at producing high-quality publication ready network graphics, these graphics are static. Fortunately, developers have started exploring how to take network graphics and deliver them to web-based platforms where users can interact with the diagrams. This chapter explores a few of these more specialized network graphic techniques, as well as demonstrating how to produce some simple web-based interactive network diagrams.

In computer cinematography, the process of lighting design involves placing and configuring lights to define the visual appearance of environments and to enhance story elements. This process is labor intensive and time consuming, primarily because lighting artists receive poor feedback from existing tools: interactive previews have very poor quality, while final-quality images often take hours to render.This paper presents an interactive cinematic lighting system used in the production of computer-animated feature films containing environments of very high complexity, in which surface and light appearances are described using procedural RenderMan shaders. Our system provides lighting artists with high-quality previews at interactive framerates with only small approximations compared to the final rendered images. This is accomplished by combining numerical estimation of surface response, image-space caching, deferred shading, and the computational power of modern graphics hardware.Our system has been successfully used in the production of two feature-length animated films, dramatically accelerating lighting tasks. In our experience interactivity fundamentally changes an artist's workflow, improving both productivity and artistic expressiveness.