The gluNurbsCurve function defines the shape of a NURBS curve.
void gluNurbsCurve( GLUnurbsObj *nobj, GLint nknots, GLfloat *knot, GLint stride, GLfloat *ctlarray, GLint order, GLenum type );
- The NURBS object (created with gluNewNurbsRenderer).
- The number of knots in knot. The nknots parameter equals the number of control points plus the order.
- An array of nknots nondecreasing knot values.
- The offset (as a number of single precisionfloating-point values) between successive curve control points.
- A pointer to an array of control points. The coordinates must agree with type.
- The order of the NURBS curve. The order parameter equals degree + 1; hence a cubic curve has an order of 4.
- The type of the curve. If this curve is defined within a gluBeginCurve/gluEndCurve pair, then the type can be any of the valid one-dimensional evaluator types (such as GL_MAP1_VERTEX_3 or GL_MAP1_COLOR_4). Between a gluBeginTrim/gluEndTrim pair, the only valid types are GLU_MAP1_TRIM_2 and GLU_MAP1_TRIM_3.
When gluNurbsCurve appears between a gluBeginCurve/gluEndCurve pair, it describes a curve to be rendered. You associate positional, texture, and color coordinates by presenting each as a separate gluNurbsCurve between a gluBeginCurve/gluEndCurve pair. Do not make more than one call to gluNurbsCurve for color, position, and texture data within a single gluBeginCurve/gluEndCurve pair. Make exactly one call to describe the position of the curve (a type of GL_MAP1_VERTEX_3 or GL_MAP1_VERTEX_4).
When gluNurbsCurve appears between a gluBeginTrim/gluEndTrim pair, it describes a trimming curve on a NURBS surface. If type is GLU_MAP1_TRIM_2, it describes a curve in two-dimensional (u and v) parameter space. If it is GLU_MAP1_TRIM_3, it describes a curve in two-dimensional homogeneous (u, v, and w) parameter space. For more discussion about trimming curves, see gluBeginTrim.
The following functions render a textured NURBS curve with normals:
gluBeginCurve(nobj); gluNurbsCurve(nobj, ..., GL_MAP1_TEXTURE_COORD_2); gluNurbsCurve(nobj, ..., GL_MAP1_NORMAL); gluNurbsCurve(nobj, ..., GL_MAP1_VERTEX_4); gluEndCurve(nobj);
Windows NT/2000: Requires Windows NT 3.5 or later.
Windows 95/98: Requires Windows 95 or later. Available as a redistributable for Windows 95.
Header: Declared in Glu.h.
Library: Use Glu32.lib.