Graphics Tools and Utilities
Graphics programming is fun (at least, as long as one is not to track
a memory leak or some other nasty bug ;-), and it is even more fun when
the right tools are at hand.
Here comes a short list of some of the tools which I have recently implemented.
A very extensive list of graphics and math goodies is provided by
Dave Eberly's Geometric Tools.
- Intersection Tests
- Checking for intersections among triangles, line segments, cylinders
and spheres is a basic prerequisite for quite a few of the projects
I have been involved in. (See, for instance,
Collision detection for VR,
M. Held (1997):
``ERIT: A Collection of Efficient and Reliable Intersection Tests''.
Journal of Graphics Tools
2(4):25-44, February 1999.
Please note: This code is not in the public domain, and no parts of it
may be sold or re-distributed in its original version or in a modified
version, in any format, without obtaining the prior written consent of
the copyright holder. Please note that this excludes the use of ERIT
within any open-source, shareware or commercial code.
- Computing Adjacencies
- The WWW offers tons of geometric models. Unfortunately, most of those
models tend to come as so-called "polygon soups", i.e., as unstructured
lists of triangles that lack any topological information on adjacencies.
Clearly, an all-pairs check is too costly for anything but small models.
Thus, I implemented a sorting scheme which recovers adjacencies among
N triangles in time O(N logN). In addition,
this module also does a little bit of data clean-up.
- Polyhedral Approximations
- For various applications I needed polyhedral approximations of surfaces
of revolution. My software currently is able to compute triangulated
approximations of spheres, sphere caps, cylinders, and of general solids
generated by rotating a polygon around an axis.
- Discrete-Orientation Polytopes
- Jointly implemented with
see also the WWW page on
- PSLG Editor
- Jointly designed with
F. Gusenbauer (2005):
"Algorithmenbibliothek für PSLG-Grafikeditoren mit
effizienter Online-Validierung zum Einsatz in
The following images show objects computed by means of my graphics tools.
Click on an image icon in order to
see the full-size image. The full-size images have 800x800 pixels.)
|| This image shows a polyhedral approximation of a tool used for NC
|| This image shows a polyhedral approximation of another tool used for NC
|| A 26-dop of a WW-II aircraft.