OpenGL man pages
gluQuadricOrientation - specify inside/outside orientation for quadrics
void gluQuadricOrientation( GLUquadricObj *qobj,
GLenum orientation )
qobj Specifies the quadrics object (created with gluNewQuadric).
orientation Specifies the desired orientation. Valid values are
GLU_OUTSIDE and GLU_INSIDE.
gluQuadricOrientation specifies what kind of orientation is desired for
quadrics rendered with qobj. The orientation values are as follows:
GLU_OUTSIDE Quadrics are drawn with normals pointing outward.
GLU_INSIDE Normals point inward. The default is GLU_OUTSIDE.
Note that the interpretation of outward and inward depends on the quadric
gluNewQuadric, gluQuadricDrawStyle, gluQuadricNormals, gluQuadricTexture
Fri Dec 6 11:18:03 EST 1996
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