Showing papers on "Graphics published in 2003"

AtomEye: an efficient atomistic configuration viewer

Abstract: AtomEye is free atomistic visualization software for all major UNIX platforms It is based on a newly developed graphics core library of higher quality than the X-window standard, with area-weighted anti-aliasing An order-N neighbourlist algorithm is used to compute the bond connectivity The functionalities of AtomEye include: parallel and perspective projections with full three-dimensional navigation; customizable bond and coordination number calculation; colour-encoding of arbitrary user-defined quantities; local atomic strain invariant; coloured atom tiling and tracing; up to 16 cutting planes; periodic boundary condition translations; high-quality JPEG, PNG and EPS screenshots; and animation scripting The program is efficient compared to OpenGL hardware acceleration by employing special algorithms to treat spheres (atoms) and cylinders (bonds), in which they are rendered as primitive objects rather than as composites of polygons AtomEye can handle more than one million atoms on a PC with 1 GB memory It is a robust, low-cost tool for surveying nanostructures and following their evolutions

Linear algebra operators for GPU implementation of numerical algorithms

Abstract: In this work, the emphasis is on the development of strategies to realize techniques of numerical computing on the graphics chip. In particular, the focus is on the acceleration of techniques for solving sets of algebraic equations as they occur in numerical simulation. We introduce a framework for the implementation of linear algebra operators on programmable graphics processors (GPUs), thus providing the building blocks for the design of more complex numerical algorithms. In particular, we propose a stream model for arithmetic operations on vectors and matrices that exploits the intrinsic parallelism and efficient communication on modern GPUs. Besides performance gains due to improved numerical computations, graphics algorithms benefit from this model in that the transfer of computation results to the graphics processor for display is avoided. We demonstrate the effectiveness of our approach by implementing direct solvers for sparse matrices, and by applying these solvers to multi-dimensional finite difference equations, i.e. the 2D wave equation and the incompressible Navier-Stokes equations.

Cg: a system for programming graphics hardware in a C-like language

Abstract: The latest real-time graphics architectures include programmable floating-point vertex and fragment processors, with support for data-dependent control flow in the vertex processor. We present a programming language and a supporting system that are designed for programming these stream processors. The language follows the philosophy of C, in that it is a hardware-oriented, general-purpose language, rather than an application-specific shading language. The language includes a variety of facilities designed to support the key architectural features of programmable graphics processors, and is designed to support multiple generations of graphics architectures with different levels of functionality. The system supports both of the major 3D graphics APIs: OpenGL and Direct3D. This paper identifies many of the choices that we faced as we designed the system, and explains why we made the decisions that we did.

Level Set Methods

Abstract: The level set method for capturing moving fronts was introduced in 1987 by Osher and Sethian [401]. It has proven to be phenomenally successful as a numerical device. For example, as of June 2002, typing in “Level Set Methods” on Google’s search engine gives roughly 2800 responses and the original article has been cited over 530 times (according to web of science). Applications range from capturing multiphase fluid dynamical flows, to graphics, e.g. special effects in Hollywood, to visualization, image processing, control, epitaxial growth, computer vision and include many others. In this chapter we shall give an overview of the numerical technology and of applications in imaging science. These will include surface interpolation, solving PDE’s on manifolds, visibility, ray tracing, segmentation (including texture segmentation) and restoration.

The space - time cube revisited from a geovisualization perspective

Abstract: At the end of the sixties Hagerstrand introduced a space-time model which included features such as a Space-TimePath, and a Space-Time-Prism. His model is often seen as the start of the time-geography studies. Throughout the years his model has been applied and improved to understand our movements through space. Problems studied can be found in different fields of geography, and range from those on an individual movement to whole theories to optimize transportation. From a visualization perspective the Space-Time-Cube was the most prominent element in Hagerstrand’s approach. In its basic appearance these images consist of a cube with on its base a representation of geography (along the x- and y-axis), while the cube’s height represents time (z-axis). A typical Space-Time-Cube could contain the space time-paths of for instance individuals or bus routes. However, when the concept was introduced the options to create the graphics were limited to manual methods and the user could only experience the single view created by the draftsperson. An alternative view on the cube would mean to go through a laborious drawing exercise. Today’s software has options to automatically create the cube and its contents from a database. Data acquisition of space-time paths for both individuals and groups is also made easier using GPS. Today, the user’s viewing environment is, by default, interactive and allows one to view the cube from any direction. In this paper an extended interactive and dynamic visualization environment is proposed, and demonstrated, in which the user has full flexibility to view, manipulate and query the data in a Space-Time-Cube. Included are options to move slider planes along each of the axes to for instance select, or highlight a period in time or location in space. Examples will be discussed in which the time axis is manipulated by for instance changing world time for event time (time cartograms). Creativity should not stop here since it has been shown that especially an alternative perspective on the data will sparkle the mind with new ideas. The user should be allowed to for instance let the x- and/or y-axis be represented by other variables of the theme studied. Since the cube is seen as an integral part of a geovisualization environment the option to link other views with other graphic representation does exist.

scatterplot3d - An R Package for Visualizing Multivariate Data

Abstract: Scatterplot3d is an R package for the visualization of multivariate data in a three dimensional space. R is a "language for data analysis and graphics". In this paper we discuss the features of the package. It is designed by exclusively making use of already existing functions of R and its graphics system and thus shows the extensibility of the R graphics system. Additionally some examples on generated and real world data are provided.

Multi-resolution real-time stereo on commodity graphics hardware

Abstract: In this paper a stereo algorithm suitable for implementation on commodity graphics hardware is presented. This is important since it allows freeing up the main processor for other tasks including high-level interpretation of the stereo results. Our algorithm relies on the traditional sum-of-square-differences (SSD) dissimilarity measure between correlation windows. To achieve good results close to depth discontinuities as well as on low texture areas, a multi-resolution approach is used. The approach efficiently combines SSD measurements for windows of different sizes. Our implementation running on an NVIDIA GeForce4 graphics card achieves 50-70M disparity evaluations per second including all the overhead to download images and read-back the disparity map, which is equivalent to the fastest commercial CPU implementations available. An important advantage of our approach is that rectification is not necessary so that correspondences can just as easily be obtained for images that contain the epipoles. Another advantage is that this approach can easily be extended to multi-baseline stereo.

Linear algebra operators for GPU implementation of numerical algorithms

Abstract: In this work, the emphasis is on the development of strategies to realize techniques of numerical computing on the graphics chip. In particular, the focus is on the acceleration of techniques for s...

CULLIDE: interactive collision detection between complex models in large environments using graphics hardware

Abstract: We present a novel approach for fast collision detection between multiple deformable and breakable objects in a large environment using graphics hardware. Our algorithm takes into account low bandwidth to and from the graphics cards and computes a potentially colliding set (PCS) using visibility queries. It involves no precomputation and proceeds in multiple stages: PCS computation at an object level and PCS computation at sub-object level, followed by exact collision detection. We use a linear time two-pass rendering algorithm to compute each PCS efficiently. The overall approach makes no assumption about the input primitives or the object's motion and is directly applicable to all triangulated models. It has been implemented on a PC with NVIDIA GeForce FX 5800 Ultra graphics card and applied to different environments composed of a high number of moving objects with tens of thousands of triangles. It is able to compute all the overlapping primitives between different objects up to image-space resolution in a few milliseconds.

Discrete multiscale vector field decomposition

Abstract: While 2D and 3D vector fields are ubiquitous in computational sciences, their use in graphics is often limited to regular grids, where computations are easily handled through finite-difference methods. In this paper, we propose a set of simple and accurate tools for the analysis of 3D discrete vector fields on arbitrary tetrahedral grids. We introduce a variational, multiscale decomposition of vector fields into three intuitive components: a divergence-free part, a curl-free part, and a harmonic part. We show how our discrete approach matches its well-known smooth analog, called the Helmotz-Hodge decomposition, and that the resulting computational tools have very intuitive geometric interpretation. We demonstrate the versatility of these tools in a series of applications, ranging from data visualization to fluid and deformable object simulation.

Sequential point trees

Abstract: In this paper we present sequential point trees, a data structure that allows adaptive rendering of point clouds completely on the graphics processor. Sequential point trees are based on a hierarchical point representation, but the hierarchical rendering traversal is replaced by sequential processing on the graphics processor, while the CPU is available for other tasks. Smooth transition to triangle rendering for optimized performance is integrated. We describe optimizations for backface culling and texture adaptive point selection. Finally, we discuss implementation issues and show results.

System and method for managing visual structure, timing, and animation in a graphics processing system

Abstract: A visual tree structure as specified by a program is constructed and maintained by a visual system's user interface thread. As needed, the tree structure is traversed on the UI thread, with changes compiled into change queues. A secondary rendering thread that handles animation and graphical composition takes the content from the change queues, to construct and maintain a condensed visual tree. Static visual subtrees are collapsed, leaving a condensed tree with only animated attributes such as transforms as parent nodes, such that animation data is managed on the secondary thread, with references into the visual tree. When run, the rendering thread processes the change queues, applies changes to the condensed trees, and updates the structure of the animation list as necessary by resampling animated values at their new times. Content in the condensed visual tree is then rendered and composed. Animation and a composition communication protocol are also provided.

A multigrid solver for boundary value problems using programmable graphics hardware

Abstract: We present a case study in the application of graphics hardware to general-purpose numeric computing. Specifically, we describe a system, built on programmable graphics hardware, able to solve a variety of partial differential equations with complex boundary conditions. Many areas of graphics, simulation, and computational science require efficient techniques for solving such equations. Our system implements the multigrid method, a fast and popular approach to solving large boundary value problems. We demonstrate the viability of this technique by using it to accelerate three applications: simulation of heat transfer, modeling of fluid mechanics, and tone mapping of high dynamic range images. We analyze the performance of our solver and discuss several issues, including techniques for improving the computational efficiency of iterative grid-based computations for the GPU.

Three varieties of realism in computer graphics

Abstract: This paper describes three varieties of realism that need to be considered in evaluating computer graphics images and defines the criteria that need to be met if each kind of realism is to be achieved. The paper introduces a conceptual framework for thinking about realism in images, and describes a set of research tools for measuring image realism and assessing its value in graphics applications.

CInDeR : collision and interference detection in real time using graphics hardware

Abstract: Collision detection is a vital task in almost all forms of computer animation and physical simulation. It is also one of the most computationally expensive, and therefore a frequent impediment to efficient implementation of real-time graphics applications. We describe how graphics hardware can be used as a geometric co-processor to carry out the bulk of the computation involved with collision detection. Hardware frame buffer operations are used to implement a ray-casting algorithm which detects static interference between solid polyhedral objects. The algorithm is linear in both the number of objects and number of polygons in the models. It also requires no preprocessing or special data structures.

Markup language and object model for vector graphics

Abstract: An element object model and a vector graphics markup language for using that element object model in a manner that allows program code developers to consistently interface with a scene graph data structure to produce graphics. The vector graphics element object model generally corresponds to shape elements and other elements including image and video elements that correlate with a scene graph object model of the scene graph. Markup may be parsed into data including elements in an element tree that is translated into the objects of a scene graph data structure. Other markup may be translated directly into data and calls that create the scene graph objects. The markup language provides distinct ways to describe an element, including a simple string format or complex property syntax, which may be named, enabling reuse in other locations in the markup.

The GPU enters computing's mainstream

Abstract: The Siggraph/Eurographics Graphics Hardware 2003 workshop, held in San Diego, will likely be remembered as a turning point in modern computing. In one of those rare moments when a new paradigm visibly begins changing general-purpose computing's course, what has traditionally been a graphics-centric workshop shifted its attention to the nongraphics applications of the graphics processing unit. GPUs, made by Nvidia (www.nvidia.com) and ATI (www.ati.com), function as components in graphics subsystems that power everything from Microsoft's Xbox to high-end visualization systems from Hewlett-Packard and SGI. The GPUs act as coprocessors to CPUs such as Intel's Pentium, using a fast bus such as Intel's Advanced Graphics Port. AGP8x has a peak bandwidth of 2.1 gigabytes per second - speed it needs to avoid inflicting bus starvation on data-hungry GPU coprocessors.

Interactive deformation and visualization of level set surfaces using graphics hardware

Abstract: Deformable isosurfaces, implemented with level-set methods, have demonstrated a great potential in visualization for applications such as segmentation, surface processing, and surface reconstruction. Their usefulness has been limited, however, by their high computational cost and reliance on significant parameter tuning. This paper presents a solution to these challenges by describing graphics processor (GPU) based on algorithms for solving and visualizing level-set solutions at interactive rates. Our efficient GPU-based solution relies on packing the level-set isosurface data into a dynamic, sparse texture format. As the level set moves, this sparse data structure is updated via a novel GPU to CPU message passing scheme. When the level-set solver is integrated with a real-time volume renderer operating on the same packed format, a user can visualize and steer the deformable level-set surface as it evolves. In addition, the resulting isosurface can serve as a region-of-interest specifier for the volume renderer. This paper demonstrates the capabilities of this technology for interactive volume visualization and segmentation.

Private addressing in a multi-processor graphics processing system

Abstract: Systems and methods for private addressing in a multi-processor graphics processing subsystem having a number of memories and a number of graphics processors. Each of the memories includes a number of addressable storage locations, and storage locations in different memories may share a common global address. Storage locations are uniquely identifiable by private addresses internal to the graphics processing subsystem. One of the graphics processors is able to access a location in a particular memory by referencing its private address.

System and method for network transmission of graphical data through a distributed application

Abstract: Systems and methods for network transmission of three-dimensional graphical data are disclosed. A single graphical application instance can virtually and efficiently exist on multiple local or remote display systems by directly sharing its raw rendered framebuffer memory information among all local or remote graphics accelerators, thus avoiding the need to re-render any application information again on each node. An internal graphics card is used to scale the rendered data prior to transmission. This graphics scaling eliminates the need for data compression or image compression and achieves an adaptive, hardware-accelerated reduction in network bandwidth. Furthermore, since all memory and remote processing support tasks are performed within the graphics card, the CPU, system bus, and memory bandwidth remain available to the system and other applications.

Programming multiple chips from a command buffer

Abstract: A CPU selectively programs one or more graphics devices by writing a control command to the command buffer that designates a subset of graphics devices to execute subsequent commands. Graphics devices not designated by the control command will ignore the subsequent commands until re-enabled by the CPU. The non-designated graphics devices will continue to read from the command buffer to maintain synchronization. Subsequent control commands can designate different subsets of graphics devices to execute further subsequent commands. Graphics devices include graphics processing units and graphics coprocessors. A unique identifier is associated with each of the graphics devices. The control command designates a subset of graphics devices according to their respective unique identifiers. The control command includes a number of bits. Each bit is associated with one of the unique identifiers and designates the inclusion of one of the graphics devices in the first subset of graphics devices.

Image processing apparatus and method of same

Abstract: An image processing apparatus, able to improve the pixel fill rate and able to prevent an increase of memory resources and increase of memory access, provided with a color calculation circuit for performing pixel level processing based on supplied first attribute parameters of the Z and color (R, G, B) data and outputting second attribute parameters and (x, y) coordinate data supplied by a DDA circuit together with the results and a sub primitive generation circuit for expanding a plurality of stamps to a plurality of sub primitives (sub stamps) based on the second attribute parameters of the color calculation circuit, generating expanded coordinates corresponding to the expanded sub stamps based on the (x, y) coordinate data of the DDA circuit, and outputting the same as the drawing parameters after expansion and the expanded graphics drawing coordinates to a memory controller, and a method of the same.

Reeb graph based shape retrieval for cad

Abstract: Our recent work has described a framework for matching solid of mechanical artifacts models based on scale-space feature decomposition. In this work we adopt a method of comparing solid models based on Multiresolutional Reeb Graphs (MRG) similarity computations. This method was originally proposed by Hilaga et al. in [1]. Reeb Graph technique applies MRG structure to comparisons of approximate models found in the graphics community, such as polygonal meshes, faceted representation and Virtual Reality Modeling Language (VRML) models. First, we provide a brief review of shape matching using Multiresolutional Reeb Graphs and present an approach to matching solid models. Second, we show the performance of the Reeb Graph technique when handling primitive CAD models, such as cubes and spheres; then we perform experiments with more complex models, such as LEGO models and mechanical parts, and we discuss Reeb Graph technique’s performance on complex CAD models. Third, we emphasize several problems with the existing technique. Finally, we conclude with discussion of future work.

The CHAI Libraries

Abstract: Keywords: virtual reality ; physics-based modeling ; graphics ; haptics ; [VRAI] Reference LSRO2-CONF-2003-003 Record created on 2005-02-04, modified on 2017-05-10

Syzygy: native PC cluster VR

Abstract: The Syzygy software library consists of tools for programming VR applications on PC clusters. Since the PC cluster environment presents application development constraints, it is impossible to simultaneously optimize for efficiency, flexibility, and portability between the single-computer and cluster cases. Consequently Syzygy includes two application frameworks: a distributed scene graph framework for rendering a single application's graphics database on multiple rendering clients, and a master/slave framework for applications with multiple synchronized instances. Syzygy includes a simple distributed OS and supports networked input devices, sound renderers, and graphics renderers, all built on a robust networking layer.