[ont.events] Geometric Continuity and Corner Cutting Algorithms for Piecewise Polynomial Curves.

ylfink@water.UUCP (10/28/87)

DEPARTMENT OF COMPUTER SCIENCE
UNIVERSITY OF WATERLOO
SEMINAR ACTIVITIES

COMPUTER GRAPHICS SEMINAR

                    - Monday, November 2, 1987

Dr.  Charles  A.  Micchelli,  of  IBM,  will  speak  on
``Geometric  Continuity  and  Corner Cutting Algorithms
For Piecewise Polynomial Curves''.

TIME:                 2:00 PM

ROOM:              MC 6082

ABSTRACT

This  talk  deals with two problems related to modeling
curves  by  piecewise  polynomials.   The  main problem
discussed  is  that  of  various interpretations of the
notion  of ``visual'' continuity of curves.  This leads
us  into  methods  for  curve  representation that have
``shape parameters'' which can be used to model a curve
while  still  preserving  its  visual  smoothness.  The
resulting  piecewise  polynomial  spaces  determined by
connection  matrices  are  analyzed  and shown to share
familiar properties of spline functions.

The  second issues we address concerns algorithms which
successively  compute  convex  combinations of adjacent
control  points  to  pass from some preferred piecewise
polynomial  representation  of  a  curve  to its Bezier
representation.   We  discuss  circumstances when there
are   such  corner  cutting  algorithms  and  show,  in
particular,  that  this is available for curves modeled
piecewise  polynomials determined by certain connection
matrices.