sync code with last improvements from OpenBSD

doc/gl-docs/GLU/pwlcurve.3gl

@@ -0,0 +1,69 @@
+'\" e
+'\"! eqn | mmdoc
+'\"macro stdmacro
+.ds Vn Version 1.2
+.ds Dt 6 March 1997
+.ds Re Release 1.2.0
+.ds Dp May 02 11:53
+.ds Dm 37 pwlcurve.
+.ds Xs 35475 4 pwlcurve.gl
+.TH GLUPWLCURVE 3G
+.SH NAME
+.B "gluPwlCurve
+\- describe a piecewise linear NURBS trimming curve
+
+.SH C SPECIFICATION
+void \f3gluPwlCurve\fP(
+GLUnurbs* \fInurb\fP,
+.nf
+.ta \w'\f3void \fPgluPwlCurve( 'u
+	GLint \fIcount\fP,
+	GLfloat* \fIdata\fP,
+	GLint \fIstride\fP,
+	GLenum \fItype\fP )
+.fi
+
+.EQ
+delim $$
+.EN
+.SH PARAMETERS
+.TP \w'\fIstride\fP\ \ 'u 
+\f2nurb\fP
+Specifies the NURBS object (created with \%\f3gluNewNurbsRenderer\fP).
+.TP
+\f2count\fP
+Specifies the number of points on the curve.
+.TP
+\f2data\fP
+Specifies an array containing the curve points.
+.TP
+\f2stride\fP
+Specifies the offset (a number of single-precision floating-point values)
+between points on the curve.
+.TP
+\f2type\fP
+Specifies the type of curve.
+Must be either \%\f3GLU_MAP1_TRIM_2\fP or \%\f3GLU_MAP1_TRIM_3\fP.
+.SH DESCRIPTION
+\%\f3gluPwlCurve\fP describes a piecewise linear trimming curve for a NURBS surface.
+A piecewise linear curve consists of a list of 
+coordinates of points in the parameter space for the
+NURBS surface to be trimmed. These points are connected
+with line segments to form a curve. If the curve is
+an approximation to a curve that is not piecewise linear, 
+the points should be close enough in parameter space that the 
+resulting path appears curved at the resolution used in the application.
+.P
+If \f2type\fP is
+\%\f3GLU_MAP1_TRIM_2\fP, then it describes a curve in two-dimensional (\f2u\fP 
+and \f2v\fP) parameter space. If it is \%\f3GLU_MAP1_TRIM_3\fP, then it
+describes a curve in two-dimensional homogeneous (\f2u\fP, \f2v\fP,
+and \f2w\fP) parameter space. 
+See the \%\f3gluBeginTrim\fP reference page for more information 
+about trimming curves. 
+.SH NOTES
+To describe a trim curve that closely follows the contours of a NURBS 
+surface, call \%\f3gluNurbsCurve\fP.
+.SH SEE ALSO
+\%\f3gluBeginCurve(3G)\fP, \%\f3gluBeginTrim(3G)\fP, \%\f3gluNewNurbsRenderer(3G)\fP, \%\f3gluNurbsCurve(3G)\fP
+