Institute for Visualization and Interactive Systems
CrashViewer in general
CrashViewer in general
The application crashViewer has been developed as testing-platform to implement various functions in the range of pre- and postprocessing of crashsimulations. The crashViewer has been implemented in C++ and consists of various modules, the most important are presented in the following:
Viewer is the central application module and takes on the interaction control. As GUI (graphical user interface) X11/Motif is used presently to enable the user to make entries via dialogboxes and menus. The presentation-window is based on the high-level-graphics library Cosmo3D/OpenGL Optimizer.
Reader combines varios libraries for the input of pre- and postprocessing data. From here the necessary data of the given fileformats is transformed into an internal, objectoriented datastructure.
GeoBuilder represents the part of the aplication that initialises objects to be displayed of the internal data with the aid of high-level-3D-graphic-APIs. So far the simulationmodel can be converted to scenegraphs for Open Inventor and Cosmo 3D which are then being traversed for the interactive display.
Func contains the algorithms needed by the various functionalities at pre- and postprocessing.
The modular structure of crashViewer permits a quick adjustment to new or further fileformats as well as future graphiclibraries.
For the display the graphiclibrariy Cosmo3D/OpenGL Optimizer has been used which is based on the low-level-graphiclibrary OpenGL. Cosmo3D provides objects for representation of geometric models in a directed acyclic graph, OpenGL Optimizer contains several tools for optimizing this scenegraph and to enhance the performance of the representation of the normally very complex models.
This picture shows the surface of crashViewer. The user interacts
via 2D- or 3D-mouse, keyboard, bitmap-buttons, menus and dialog-boxes.
General Functionalities
Each scene can be saved in the binary csb-fileformat and be restored again.
Current settings as well as position of camera, backgroundcolor etc. can be saved in an environment-file and restored again in a later session.
There are various functions to choose the camera-setting, among others standard views and the search for and display of points, nodes, elements or components.
Components can be selectively blinded out or displayed via mouseclick or their ID.
Single (if necessary high-resolution) snapshots can be made of the currently displayed view. Furthermore a record-mode can also be activated that allows the creation of digital videos.
The scene can be (temporarily) restricted to some part interesting for the user, to do this either the selection-objects (box, sphere) or the viewing-frustum of the current camera-setting can be used. For complex models this results in a significant increase of image frequency.
For the rendering various culling-techniques can be activated.
The representation of geometry can be made more efficient by optimization-steps (as quadrilateral-stripping or decimation of polygons).
Finally many standard-settings can be preset in an initialization-file.
