From: 0001811496@mcimail.com (Carl Oppedahl)
Newsgroups: comp.patents
Subject: Re: Recent Australian Court Decision
Date: 9 Apr 92 06:40:57 GMT

pjt (patents@cs.su.oz.au) writes on the subject of a Recent Australian 
Decision:
 
>In a recent Australian Federal Court decision, the judge took
>a very liberal view of what is patentable subject matter and
>extended it to the realms of software algorithms.
 
>The patent application (AU 73701/87) based on a US basic
>application filed 13 June 1986, Number Unknown) related to 
>the use of integer arithmetic to produce improved curves on a screen. 
 
I pulled it out of World Patents Index.  There were about 2287 patent 
applications filed that day, and exactly one of them contained the words
CURVE and INTEGER.  It was U.S. Appl. No. 873,902, which issued on 
July 26, 1988 as US Pat. No. 4,760,548, owned by IBM.  There's also a 
Canadian patent 1,277,787 issued Dec. 11, 1990 and pending European patent
application.
 
Here are two Derwent abstracts.
 
Abstract: (EP 249705)
         The representation of the curved image is produced from a set of
    control points defining the curve which are input for each dimension
    and from a number of intervals of the curve to be computed.  Following
    initialisation (60), a set of scaled vector coefficient integers is
    computed (64) for each dimension from the set of input control points
    for that dimension and the interval integer number.  The forward
    difference interval coefficient integers are computed (66) for each
    dimension for each interval from the sealed vector coefficient integers
    for the respective dimension and from the interval integer number.
         The curve co-ordinate values are computed for each interval for
    each dimension from the forward difference interval coefficient
    integers for the respective dimension for each interval and from the
    respective sealing parameter.  The curve is displayed by displaying
    curve coordinate points according to computed curve coordinate values
    for each dimension and straight lines which successively connect the
    computed curve coordinate points.
 
         ADVANTAGE - Curves are produced using B-spline form more
    accurately than have been achieved using floating point methods. 
 
Abstract (US): US 4760548
         The production method comprises the steps of computing a set of
    scaled vector coefficient integers for each dimension from the set of
    input control points for that dimension and from a scaling parameter.
    Forward difference interval coefficient intergers are countered for
    each dimension for each interval from the scaled vector coefficient
    integers for that dimension and the interval integer number.
         The curve coordinate values are computed for each interval for
    each dimension from the forward difference interval coefficient
    integers for the dimension for each interval and the scaling parameter.
     The curve is displayed by displaying curve coordinate points in
    accordance with the computed curve coordinate values for each dimension
    and a number of straight lines which successively cconnect the
    computed curve coordinate points.
 
Carl Oppedahl
30 Rockefeller Plaza
New York, NY  10112-0228