Feature Lines for Illustrating Medical Surface Models: Mathematical Background and Survey

This paper provides a tutorial and survey for a specific kind of illustrative visualization technique: feature lines. We examine different feature line methods. For this, we provide the differential geometry behind these concepts and adapt this mathematical field to the discrete differential geometry. All discrete differential geometry terms are explained for triangulated surface meshes. These utilities serve as basis for the feature line methods. We provide the reader with all knowledge to re-implement every feature line method. Furthermore, we summarize the methods and suggest a guideline for which kind of surface which feature line algorithm is best suited. Our work is motivated by, but not restricted to, medical and biological surface models.Comment: 33 page

Affect, Relationality and the 'Problem of Personality'

This peer-reviewed journal article sets out an argument regarding the importance of genealogical work for understanding concepts such as affect and suggestion

A unified framework for isotropic meshing based on narrow-band Euclidean distance transformation

In this paper, we propose a simple-yet-effective method for isotropic meshing relying on Euclidean distance transformation based centroidal Voronoi tessellation (CVT). Our approach improves the performance and robustness of computing CVT on curved domains while simultaneously providing high-quality output meshes. While conventional extrinsic methods compute CVTs in the entire volume bounded by the input model, we restrict the computation to a 3D shell of user-controlled thickness. Taking voxels which contain surface samples as sites, we compute the exact Euclidean distance transform on the GPU. Our algorithm is parallel and memory-efficient, and can construct the shell space for resolutions up to 20483 at interactive speed. The 3D centroidal Voronoi tessellation and restricted Voronoi diagrams are also computed efficiently on the GPU. Since the shell space can bridge holes and gaps smaller than a certain tolerance, and tolerate non-manifold edges and degenerate triangles, our algorithm can handle models with such defects, which typically cause conventional remeshing methods to fail. Our method can process implicit surfaces, polyhedral surfaces, and point clouds in a unified framework. Computational results show that our GPU-based isotropic meshing algorithm produces results comparable to state-of- the-art techniques, but is significantly faster than conventional CPU-based implementations.MOE (Min. of Education, S’pore)Published versio

Aion, Khronos.

Whereas khronos – as represented by Kronos, the god who devours his own children – presents us with all the characteristics of ‘time', aiôn, by way of contrast, is a term for which there is no modern equivalent. In Homeric poetry, aiôn designates the vital fluid, and hence a man's lifespan and destiny, the intensity of a portion of time. But when Plato, in the Timaeus, relates aiôn to divine life rather than to a human portion, we encounter ‘eternity' in the sense which Aristotle will also retain for his first ‘unmoved mover', and which Plotinus will construe as the way in which Being exists. Khronos becomes the ‘moving image' of aiôn, and in the Neoplatonist readings, its ‘son'. Thus, the Greek opposition between aiôn and khronos does not coincide with any of those with which we are familiar. Transliterated into aevum, aiôn was adopted and adapted for the purposes of Christian theology. For Aquinas, ‘strictly speaking, aevum and aeternitas are no more distinct than are anthropos and homo'. However, in the course of the 13th Century, aevum detached itself from aeternitas and began to designate something intermediate between time and eternity. Ockham redefined this unstable intermediate position in terms of a common, homogeneous time, which provided the foundation for the functional-objective representation of time in the Classical age (Descartes). In the development of speculative philosophies of history in the wake of Kant, the notions of aiôn and aevum were put to work again, in an entirely different doctrinal context. The Schellingian Ewigkeit rediscovered the vitalism of the aiôn, which in turn informed the Bergsonian experience of duration

L'Oeil-Cerveau: nouvelles histoires de la peinture moderne.

This book offers a new philosophical history of modern painting in France from Delacroix to Cezanne, via Manet, Seurat and Gauguin. Basing itself on statements by the painters themselves, it reconstructs this history as a series of changes in the relationship between the eye and the brain. In particular, it charts what it calls the ‘denaturalisation' and ‘cerebralization' of the painter's eye, drawing upon a philosophical interpretation of Hyppolite Taine's psycho-physiological studies of hallucination. (The guiding proposition of Taine's writings is that every perception, every image, and every sensation are by their very nature hallucinatory.) It is argued that the ‘Eye-Brain' of the modern painter is best conceived as the vector of a ‘monism of sensation' that seeks to produce a ‘true hallucination' of the world. As such, it produces an experimental practice that is irreducible to relations between subject and object, as conventionally conceived. It invents a new form of the cerebral, freeing the eye from its character as a fixed organ and from its representational function. This experimentation finds its philosophical correlate in Goethe's interrogation of colour, from which the book sets out. The history of modern painting in France is thereby presented as a continuous destruction of systems of representation and an ever-renewed deconstruction of the notion of the image

La Pensée-Matisse: portrait de l'artiste en hyperfauve.

This work aims to show that Matisse's œuvre is of fundamental concern to contemporary philosophy of art because it establishes the continuity of vitalist thinking. Matisse encountered vitalism through Nietzsche and Bergson, at a time when it was absent from the history of philosophy. Above all, what Matisse offers philosophy is an aesthetics that breaks with every form of ‘phenomenology of art'. Matisse is not a philosopher but his oeuvre is nonetheless the vector of new thought about colour. However, his contribution is not so much ‘the liberation of colour', as persued by both his predecessors (as a spontaneism of the expressionist liberation of the subject) and formalist modernism (in the direction of a purism of painting). Rather, colour becomes the object of a construction of relations between forces whose expressive power is neither purely optical, nor sentimental, nor symbolic, but intrinsically vital – and whose destination is not merely pictorial but environmental. This constructivist and vitalist ontology of colour leads Matisse, ultimately, to the destruction of the painting-form, by exceeding the closed world of painting. By engaging the question of the sensible as such, Matisse thus breaks through the closure of art, without reducing art to language games about art

Anti-Oedipus - thirty years on: between art and politics

A shorter version of this essay was published in Radical Philosophy 124 (March/April 2004), pp. 3-12. A revised version is forthcoming in French in the Revue de Métaphysique et de Morale (2008), Special Issue, Au-delà du Pouvoir? Lecture critique de la philosophie francaise contemporaine [Beyond Power? Critical Readings of Contemporary French Philosophy]