A Multi Dimensional visualization and analysis toolkit for astrophysics
Version : 3.1
Author(s) : Fulvio Buonomo (buonomo@cineca.it)
License : Free
Website : http://www.cineca.it/astromd/
Installs from Open Source Astronomy for Linux cd 3
Disk space required for installation is 29.18 Mb
- several different physical species are treated. For example, cosmological simulations consider both baryonic matter and dark matter. Dark matter is usually described by N-body algorithms, while baryons have a fluid-dynamics description (either Eulerian or Lagrangian). Further components, like stars or different chemical species, can be introduced and followed in a specific way. These different species requires different types of visualization. Dark matter needs particles position or velocity rendering while baryons require mesh based visualization. Furthermore particle associated quatities, like the mass density or the gravitational potential, require their calculation and visualization on a mesh.
- Simulated structures have a fully three-dimensional distribution. Therefore it is necessar to have a clear 3D representation and efficient and fast tools of navigation, selection, zoom and the possibilty of improving the resolution and the accuracy of calculations in specific, user-selected, regions
- Evolution can change dramatically the properties of the simulated objects and the information that can be retrived, therefore it is important to control efficently sequences of time-frames.
Moreover, in order to build a widely used product it was necessar to use a low cost software portable on a number of different platforms. We have chosen to use the Visualization Toolkit (VTK) by Kitware. VTK is an open source, freely available software system for 3D computer graphics, image processing, and visualization. It includes a C++ class library and several interpreted interface layers. VTK has been ported on nearly every Unix-based platform (e.g. Linux or IRIX) and PC's (Windows NT and Windows 98). The design and implementation of the library has been strongly influenced by object-oriented principles. The graphics model in VTK is at a higher level of abstraction than rendering libraries like OpenGL or PEX. This means it is much easier to create useful graphics and visualization applications. In VTK applications can be written directly in C++, Tcl, Java, or Python. Using these languages it is possible to build powerful, fast and portable applications. VTK supports a wide variety of visualization algorithms including scalar, vector, tensor, texture, and volumetric methods and advanced modeling techniques. It supports stereographic rendering and can be used for virtual realty visualization. Furthermore, being easily extensible, the system allows ad hoc implementation of specific modules.
All the features described above are integrated in the AstroMD package. Furthermore efficent manipulation and analysis tools, like smoothing of the particle masses on a mesh or calculation of the power spectrum and correlation functions, are parts of the basic functionalities. AstroMD has also stereographic rendering capabilities, which makes it usable for immersive visualization (presently implemented at the Virtual Theater of CINECA). This completes and improve its capabilities in the representation of three dimensional data set.