Numerical nonrobustness is a well-known and widespread problem.
It is particularly insidiuous for geometric computation.
It is almost an axiom among researchers in this field
that current geometric software (almost without exception)
can be made to break, crash or produce wrong results.
Nonrobustness has a large economic impact, from preventing
full automation of important industrial processes, to
consuming a large fraction of programmers' and researchers' effort.
Some have declared this an unsolvable problem.
After all, if the geometric primitive to
intersect two line segments robustly has been posed as a challenge,
the robust construction of complex algorithms and
large geometric software must be a hopeless cause.
In the last 15 years, the computational geometry
and geometric modeling communities have proposed various solutions.
How much of this work is practical?
What insights we have gained?
Are there success stories?
What are the pressing research issues ahead?
These are some of the questions our speakers will address.
About the panelists: Chris Hoffmann is well-known
for his work on robustness in geometric modeling. Mark Foskey
has been involved in various projects at UNC which address
non-robustness in geometric and algebraic computations.
Sylvain Pion at INRIA is part of the major European project called
the CGAL Library which is used in industry as well as by many
research groups. CGAL is notable for its commitment
to robust geometric algorithms. Chee Yap is an early
advocate of the ``exact geometric computation'' approach,
and leads the Core Library Project at NYU.
FORMAT of the minisymposium
This takes place as
part of the SIAM Geometric Design and Computing Conference,
Sacramento, November 5-8, 2001.
20-minute talk and 5 minute question time
is allocated to each invited speaker.
For more information, contact the organizer:
Chee Yap , (212)998-3115.
SPEAKER LIST and ORGANIZER
-- Christoph Hoffmann (Purdue University)
-- Mark Foskey (University of North Carolina)
-- Sylvain Pion (INRIA, Sophia-Antipolis)
-- Jonathan Richard Shewchuk (Univ. of California, Berkeley)
-- Chee Yap (Courant Institute, New York University)
firstname.lastname@example.org (Organizer of Minisymposium)
TITLES and ABSTRACTS (and PAPERS)
NOTE: Eventually, we will add links to papers or slides for each
-- Christoph Hoffmann:
On the Role of Exact Arithmetic in Geometric Computation
-- Mark Foskey
Fast and Accurate Computations with Algebraic Primitives and Predicates
-- Sylvain Pion:
Solutions to Robustness Problems in CGAL
-- Jonathan Richard Shewchuk:
Making Roundoff Error Less Unbearable
-- Chee Yap:
Robust Geometric Computation for Everyone
ABOUT the main conference
Conference website is
This biennial event will be held
at the Holiday Inn Capitol Plaza, Sacramento, November 5-8,
This conference is a biennial event, that has gone
under several names (Geometric Modeling and Robotics, Applied
Geometry, Geometric Design, etc) since its inception in 1983.
The new title reflects a desire to broaden the scope of the
conference, to include a diverse spectrum of geometrical
computations and applications.
It is a broad-based meeting, dealing with a wide variety of