AVS Overview Visualization is a method of computing that has emerged from the combination of the latest advances in visualization software, graphics, networking, high performance systems, and industry standards. Advanced Visual System's Application Visualization System (AVS) incorporates all of these technologies into a single comprehensive visualization environment. Visualization allows the interaction between the computer system and the user to occur through the most efficient form of information exchange - visual exchange. Sight is the primary, and most efficient method for receiving, processing, analyzing and assimilating information. Visualization is changing the way scientists and engineers perform their work. The Application Visualization System (AVS) The Complete Visualization Environment AVS is the industry standard visualization application software and development environment. It is a fully functional visualization environment providing more techniques for visualizing information than any other system commercially available today. Available on the industry's major computing platforms, AVS is extensible, easily tailored, and applicable to a wide range of applications. AVS accepts the data produced by instruments, or by scientific and engineering simulation software. It provides you with the most comprehensive set of data types of any visualization system. It creates a visual display of your data in a variety of forms using a wide array of visualization techniques. AVS has a modular architecture comprised of many separate, yet tightly integrated, sub-systems that each provide important capabilities. The Building Blocks of AVS Modules are the building blocks of AVS. A module is an independent computing element (C or FORTRAN) which is represented by a rectangular icon on the screen. Each module performs a specific visualization function or set of functions. You have access to more than 110 modules provided with standard AVS. Alternatively, you can build your own modules to extend or customize AVS. External programs or subroutines written in C or FORTRAN can be easily converted into AVS modules. Public domain modules are available via email or ftp. Contact the AVS Center staff via email at avs@ncsc.org or send mail to the International AVS Center, 3021 Cornwallis Road, RTP, NC 27709 for more information. A wide range of data input, filter, mapper and data output modules are also included in AVS. Filters transform data into data, e.g. contrast stretch or edge detect. Mappers transform data into geometry, e.g isosurface or arbitrary slice. And data output modules write data to files, send data to peripheral devices, or render data, e.g displaying geometry, images and volumes on the screen. Visual Program Development The combination of the Network Editor, AVS modules, and the easy- to-use graphical user interface provides you with the premier visual programming environment. The Network Editor is a powerful, easy- to-use tool for quickly developing complex visualization processing networks, or application programs. Simply by connecting together modules through mouse-driven point-and-click operations, a "non- programmer" is capable of creating complex graphical applications without writing a single line of code. The networks created in AVS are interactively reconfigurable and re-usable by you. They may be saved and stored for future use and modification. Modules can be dynamically added, connected and deleted from new or existing networks. The AVS network editor supports rapid prototyping of visualization applications. For repeated production use, AVS also allows you to save a complete network with all the user-defined interactive controls and layout specifications as a complete, finished application. The Extensible Visualization Environment The capability to create additional modules for AVS, and even libraries of modules, enables you to extend the base capabilities of AVS for a specific application. The ease of integrating additional modules into AVS allows you to create complex scientific and engineering applications with little or no programming. You may easily incorporate your existing software programs as modules in AVS, integrating your in-house codes into the leading graphical visualization system resulting in a true integration of computation and visualization. Distributed Visualization AVS was designed from the outset to operate in distributed, multi- vendor, heterogeneous computing environments. The support for remote module execution allows modules to execute on computational servers in the network. X-terminal support allows AVS to display on 8-bit color X-terminals or workstations running the X-Window system. These distributed capabilities enable you to incorporate AVS into the networked, distributed computing model already established today. The two major architectural aspects that enable AVS to excel in a distributed environment are its modular architecture and its adherence to industry standards. The Industry Standard for Visualization AVS is now available on the major UNIX-based workstation and visualization systems. These include computer systems from Convex Computer Corporation, Cray Research Inc, Digital Equipment Corporation, Evans and Sutherland, Hewlett-Packard, IBM Corporation, Kubota Pacific Computer Inc., Set Technology Corporation, Silicon Graphics, Sun Microsystems, and Wavetracer. AVS Features AVS Geometry Viewer The AVS Geometry Viewer gives you full control over a range of low-level hardware dependent graphics capabilities with simple menu-driven parameter selections. The AVS Geometry Viewer takes advantage of all of the graphics functionality of the computer system on which it is operating. On more advanced visualization hardware systems, for example, you have full control of wireframe, Gouraud or Phong shading; 16 individually controlled colored light sources, selectable as point, directional or spot lights; surface properties such as specularity and transparency; real-time 2D and 3D texture mapping and anti-aliasing. AVS allows you to create multiple windows with different views of the same geometric object or simultaneously display multiple objects. Alphanumeric titles and labels in a variety of fonts can be added in screen or object space. You can also create scenes with a hierarchy of objects and manipulate them individually or as one or more groups. These scenes can be saved, preserving all viewing selections for later re-display. You can create and save a sequence of images and cycle through the sequence to provide animated views of dynamic behavior - all in real-time. AVS Image Viewer AVS provides a complete 2D and 3D image display capability, including real-time pan and zoom, region of interest operation, rotation and transformation, flipbook animation, and support for 8- bit, 24-bit, and floating point images. Imaging filters include look- up-table operations such as contrast stretching, pseudo-coloring and histogram balancing as well as data resizing operations such as interpolation, cropping and sampling. Volume Visualization Through the use of pre-defined AVS networks, volume data may be read into and displayed by AVS, and then viewed using the visualization techniques described in the Geometry and Image Viewers. A new class of algorithms has recently evolved for visualizing volumetric data, called 'direct volume visualization'. An AVS module, tracer, implements a highly optimized ray tracing technique for three-dimensional volumes of cells. This means that it works as well for irregular field data and unstructured cell data as it does for regularly gridded voxel arrays. Since it's implemented in portable software, it runs efficiently on all AVS platforms. tracer can create high resolution, perspective views of colored and/or shaded volumetric data from any arbitrary orientation. AVS Graph Viewer The AVS Graph Viewer allows you to visualize and output your data in the form of 2D graphs, line charts, bar charts, or contour plots. There is a menu interface for selecting line types, types of plots, labeling and annotation, and for changing the scales and styles of grids and axis. Layout Editor The Layout Editor enables you to easily and completely define the user interface. The specific control parameters may be selected, and a custom interface may be defined, thus simplifying the default interface of a control panel for each module in a network. You may also quickly assign user interface peripherals to control parameter widgets. This is an extremely powerful productivity tool when tailoring AVS for specific end-user applications. Data Probes Coordinates and values at any given point are instantly obtained and displayed using data probes. The probe is positioned using the mouse, and with a click of the mouse button underlying data values are instantly printed on the screen. AVS Data Types The following data types are available in AVS: Field data Volume data - N-dimensional (scalar, vector) Geometry data - Uniform, rectilinear, irregular Unstructured Cell Data (1D, 2D, 3D) - Physical-space coordinates Chemistry data Image data User-defined data Command Language Interpreter - CLI The AVS Command Language Interpreter (CLI) is an ASCII language that can be used to drive most of the AVS system. This allows advanced users and application developers to type AVS commands or develop scripts containing AVS commands. This feature gives you the option of developing applications that communicate directly with the Command Processor without the Network Editor. It can be used directly by you or indirectly from an AVS module to create and modify AVS networks, query and change module parameters, and control the user interface layout. Labeling and Annotation The ability to label and annotate images is very important, especially when producing hardcopy output for demonstration or publishing purposes. AVS provides you with this required capability in all of its Viewers. AVS Animator In the process of doing day-to-day research, a scientist will frequently need to visualize events that unfold through time. Animation can be a powerful tool in viewing these events and presenting the results to colleagues. The AVS Animator is designed to allow the scientist to produce a high quality animation in which control of object/camera/light placement and AVS module parameters can be handled on a per frame basis. A sophisticated keyframe editor allows you to control these parameters. Output can be sent to the display or recorded on various types of video hardware. The Data Viewer The Data Viewer is an AVS application comprised of an intuitive, easy-to-learn, user-extensible, point-and-click interface to the most frequently used visualization techniques. This application was designed with you in mind for learning about AVS. The AVS Data Viewer is also a convenient shortcut for doing similar operations on a day-by-day basis, and can be used as an aide to building AVS applications for use by others. The full power and flexibility of the AVS Network Editor is still available for users who wish to customize their applications. Unstructured Cell Data (UCD) AVS support for UCD contains a subroutine function library and a collection of AVS modules for data input, filtering, and mapping operations. UCD is used with finite element problems most commonly found in the Mechanical Computer Aided Engineering (MCAE) and Computational Fluid Dynamics (CFD) fields. The set of UCD modules includes isosurfaces, streamlines, 2D slices, annotation, data probes, hedgehogs, and volume rendering. Upstream Data Upstream data is used in the Data Probes and in direct manipulation of mapper modules. Upstream data passing allows data to flow "backwards" through a network for the purpose of ascertaining the value and coordinate information at a particular point. This information is required for the mapper module (e.g. slice plane) or Data Probe to pass on in order to display or take other action with the information. Module Library Management Tools Included in AVS is a set of tools to enable the creation, addition, deletion, and modification to modules and entire libraries of modules. Continued Evolution to meet Future Visualization Needs Enhancements and extensions to AVS continue, building on this industry-leading environment to meet future visualization needs. With it's broad industry acceptance, AVS will undoubtedly continue to define the leading edge in visualization technology. To learn more about AVS and the newest enhancements please contact AVS Inc at 617 890 4300, any AVS vendor or the International AVS Center. Stardent is a registered trademark, and AVS is a trademark of Advanced Visual Systems Inc. UNIX is a registered trademark of UNIX Systems Laboratory. X Window System is a trademark of MIT. Advanced Visual Systems Inc. sells AVS and they can be reached at Advanced Visual Systems Inc. 300 Fifth Avenue Waltham, MA 02154 (617) 890-4300 info@avs.com