1,720,957 research outputs found
Automatisation de la création de scénarios pour les scènes de la visualisation scientifique
Full text linkRÉSUMÉ: Bien que l'automatisation de la génération des chemins de caméra soit une pratique courante dans le cinéma et le jeu vidéo, elle fait preuve d'un retard important dans le milieu de la visualisation scientifique. La taille, la nature, la densité du maillage ainsi que l'absence de notions scénaristiques telles que les personnages et les actions font que l'opération d'import de règles de composition issues de domaines artistiques comme le cinéma ou la photographie ainsi que l'application des règles du montage deviennent plus complexe. Ce mémoire introduit une méthodologie qui propose une métamodélisation des attentes des scientifiques vis-à-vis de leurs données ainsi qu'une modélisation des comportements de données qui peuvent les intéresser. Ces modèles permettent de bâtir plus facilement des chemins de caméra pour des scènes numériques issues de simulations ou d'acquisitions. L'application des règles issues de la composition et du montage dans le but de produire des déplacements de caméra préservent l'intention du scientifique deviennent alors plus simple. La méthode a été expérimentée sur un ensemble de scènes issues de la mécanique des fluides et du génie biomédical; les résultats obtenus sur ces scènes nous ont permis de valider le fonctionnement de la méthodologie. Sont également proposés par la méthode un ensemble de paramètres de contrôle afin de modifier le processus de génération pour mieux l'adapter aux besoins précis que peut avoir un scientifique vis-à-vis d'une scène. ABSTRACT: Automatic camera path generation is a common practice in film making and video games. However, it demonstrated a significant delay in scientific visualization due to the size, the nature, the mesh density and the lack of scriptwriting notions such as characters and actions. In this case, importing cinematography composition, photography composition and match cut rules becomes a more complex operation. This thesis presents a methodology that provides meta-models for the scientists' visualization expectations regarding their data and for the data behaviors that may interest them. These models make the camera paths generation process more intuitive. The application of composition and match cut rules, in order to produce camera moves that preserves the scientist's intention, becomes simpler. The method was tested on a set of scenes from fluid mechanics and biomedical engineering; the obtained results showed that our approach is a simple and efficient way for producing presentation videos. A set of control parameters are also provided by this method, in order to adapt the generation process to the specific needs that a scientist can have regarding his data
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
A practical method for automatic camera paths generation in scientific visualization storytelling
No full textConcurrent Binary Trees for Large-Scale Game Components
Full text linkA concurrent binary tree (CBT) is a GPU-friendly data-structure suitable for the generation of bisection based terrain tessellations, i.e., adaptive triangulations over square domains. In this paper, we expand the benefits of this data-structure in two respects. First, we show how to bring bisection based tessellations to arbitrary polygon meshes rather than just squares. Our approach consists of mapping a triangular subdivision primitive, which we refer to as a bisector, to each halfedge of the input mesh. These bisectors can then be subdivided adaptively to produce conforming triangulations solely based on halfedge operators. Second, we alleviate a limitation that restricted the triangulations to low subdivision levels. We do so by using the CBT as a memory pool manager rather than an implicit encoding of the triangulation as done originally. By using a CBT in this way, we concurrently allocate and/or release bisectors during adaptive subdivision using shared GPU memory. We demonstrate the benefits of our improvements by rendering planetary scale geometry out of very coarse meshes. Performance-wise, our triangulation method evaluates in less than 0.2ms on console-level hardware
Sampling Visible GGX Normals with Spherical Caps
No full textImportance sampling the distribution of visible GGX normals requires sampling those of a hemisphere. In this work, we introduce a novel method for sampling such visible normals. Our method builds upon the insight that a hemispherical mirror reflects parallel light rays uniformly within a solid angle shaped as a spherical cap. This spherical cap has the same apex as the hemispherical mirror, and its aperture given by the angle formed by the orientation of that apex and the direction of incident light rays. Based on this insight, we sample GGX visible normals as halfway vectors between a given incident direction and directions drawn from its associated spherical cap. Our resulting implementation is even simpler than that of Heitz and leads to up to 39% speed-ups in our benchmarks.Computer Graphics ForumPrimitives, Surfaces, and Appearance Modeling42
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Hardware Accelerated Neural Block Texture Compression with Cooperative Vectors
No full textIn this work, we present an extension to the neural texture compression method of Weinreich and colleagues [WDOHN24]. Like them, we leverage existing block compression methods which permit to use hardware texture filtering to store a neural representation of physically-based rendering (PBR) texture sets (including albedo, normal maps, roughness, etc.). However, we show that low dynamic range block compression formats still make the solution viable. Thanks to this, we show that we can achieve higher compression ratio or higher quality at fixed compression ratio. We improve performance at runtime using a tile based rendering architecture that leverage hardware matrix multiplication engine. Thanks to all this, we render 4k textures sets (9 channels per asset) with anisotropic filtering at 1080p using only 28MB of VRAM per texture set at 0.55ms on an Intel B580.High-Performance Graphics - Symposium PapersNeural Textures and Encoding
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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