bls@texhrc.UUCP (Brian L. Sumner) (10/17/89)
I would appreciate some references to - or a quick discussion of Barycentric coordinates. I think I want to use them to answer the the following problems: 1) Given a set of n points (in 2 or 3 space), decide whether an arbitrary given point is interior to the convex hull of the n points. 2) Given a set of n points, find which edge of their convex hull is closest to an arbitrary given point. Thanks
nolan@portia.Stanford.EDU (Patrick Nolan) (10/17/89)
In article <346@texhrc.UUCP> bls@texhrc.UUCP (Brian L. Sumner) writes: >I would appreciate some references to - or a quick discussion of >Barycentric coordinates. I think I want to use them to answer the >the following problems: > >1) Given a set of n points (in 2 or 3 space), > decide whether an arbitrary given point is interior to the convex hull of > the n points. > >2) Given a set of n points, find which edge of their convex hull is closest > to an arbitrary given point. > Barycentric coordinates are used in astronomy in the study of pulsars. The Barycenter is a fancy term for the center of mass of the Solar system. When the vector to the pulsar is expressed in barycentric coordinates instead of geocentric coordinates, then you don't have to make corrections for the Doppler shift caused by the motion of the Earth. I suppose there might be a non-astronomical version of barycentric coordinates too. If so, I would like to hear about it. -- ======================================================================= Patrick Nolan Bitnet: PLN@SLACVM W. W. Hansen Laboratories Internet: nolan@meggie.stanford.edu Stanford University nolan@portia.stanford.edu
lhf@aries5.uucp (Luiz H de Figueiredo) (10/18/89)
Try the book by Preparata and Shamos on Computational Geometry. ------------------------------------------------------------------------------- Luiz Henrique de Figueiredo internet: lhf@aries5.uwaterloo.ca Computer Systems Group bitnet: lhf@watcsg.bitnet University of Waterloo ------------------------------------------------------------------------------- eof