公开(公告)号：BR8702847A

公开(公告)日：1988-03-01

申请号：BR8702847

申请日：1987-06-04

Applicant: IBM

Inventor： BAKER DAVID CURETON ,  KAUFFMAN ARTHUR A JR

IPC: G06T11/00 ,  G06T11/20 ,  G06F15/62 ,  G06F15/347

Abstract: A method and apparatus of providing a visual representation of a curve image wherein curve image data is provided by a B-Spline equation computed with a forward difference technique using scaled integer variables. The method provides for the scaling of the initial base matrix computation of the geometry vector coefficients followed by the computation of the forward difference interval coefficients using integer arithmetic. The curve coordinate values for each interval are computed from the forward difference interval coefficient integers descaled by the scaling parameter. By employing integer arithmetic in a divide approximation technique, the use of floating point arithmetic is avoided. The apparatus for producing the visual representation of the curve image includes a computational section that provides for pipelined computations of the forward difference interval coefficients to provide high-speed curve coordinate value computation.

公开(公告)号：CA1277787C

公开(公告)日：1990-12-11

申请号：CA538163

申请日：1987-05-27

Applicant: IBM

Inventor： BAKER DAVID C ,  KAUFFMAN ARTHUR A JR

IPC: G06T11/00 ,  G06T11/20 ,  G06F15/72

Abstract: METHOD AND APPARATUS FOR PRODUCING A CURVE IMAGE A method and apparatus of providing a visual representation of a curve image wherein curve image data is provided by a B-Spline equation computed with a forward difference technique using scaled integer variables. The method provides for the scaling of the initial base matrix computation of the geometry vector coefficients followed by the computation of the forward difference interval coefficients using integer arithmetic. The curve coordinate values for each interval are computed from the forward difference interval coefficient integers descaled by the scaling parameter. By employing integer arithmetic in a divide approximation technique, the use of floating point arithmetic is avoided. The apparatus for producing the visual representation of the curve image includes a computational section that provides for pipelined computations of the forward difference interval coefficients to provide high-speed curve coordinate value computation.