gluNurbsSurface

gluNurbsSurface: man2/gluNurbsSurface.xml

Use gluNurbsSurface within a NURBS (Non-Uniform Rational B-Spline) surface definition to describe the shape of a NURBS surface (before any trimming). To mark the beginning of a NURBS surface definition, use the gluBeginSurface command. To mark the end of a NURBS surface definition, use the gluEndSurface command. Call gluNurbsSurface within a NURBS surface definition only. Positional, texture, and color coordinates are associated with a surface by presenting each as a separate gluNurbsSurface between a gluBeginSurface / gluEndSurface pair. No more than one call to gluNurbsSurface for each of color, position, and texture data can be made within a single gluBeginSurface / gluEndSurface pair. Exactly one call must be made to describe the position of the surface (a type of GLU_MAP2_VERTEX_3 or GLU_MAP2_VERTEX_4 ). A NURBS surface can be trimmed by using the commands gluNurbsCurve and gluPwlCurve between calls to gluBeginTrim and gluEndTrim. Note that a gluNurbsSurface with sKnotCount knots in the direction and tKnotCount knots in the direction with orders sOrder and tOrder must have ( sKnotCount - sOrder ) times ( tKnotCount - tOrder ) control points.