BSplineSurf
Current Version
2
Subtype of
GeomSurf
Fields
Entity/Object
Variable
Description
integer
Version.
Boolean
1 if the surface is rational, 0 if the surface is polynomial (nonrational).
integer
p
Degree in first parameter.
integer
q
Degree in second parameter.
Boolean
1 if the surface is periodic in the first parameter; 0 otherwise.
Boolean
1 if the surface is periodic in the second parameter; 0 otherwise.
integer
m1
Length of first knot vector.
double[m1]
U
First knot vector.
integer
m2
Length of second knot vector.
double[m2]
V
Second knot vector.
double[n2][n1][k]
Pw
The control points of the surface. The number of control points, n1 and n2, are given by n1 = m1 - p - 1 and n2 = m2 - q - 1. If the surface is rational these are given in homogeneous coordinates and k = d + 1. If the surface is polynomial these are given in Cartesian coordinates and k = d.
Description
The generalization of B-spline curves to surfaces is a tensor product surfaces given by
For
N
i
p
, the following definition is used:
The homogeneous control points
Pw[j][i]
used in the serialization of a rational surface have the components:
A polynomial surface has all weights equal to 1.
See also
BezierSurf
