glNormal

Name

glNormal — set the current normal vector

C Specification

 void glNormal3b( GLbyte nx, GLbyte ny, GLbyte nz);
 void glNormal3d( GLdouble nx, GLdouble ny, GLdouble nz);
 void glNormal3f( GLfloat nx, GLfloat ny, GLfloat nz);
 void glNormal3i( GLint nx, GLint ny, GLint nz);
 void glNormal3s( GLshort nx, GLshort ny, GLshort nz);

Parameters

nx, ny, nz

Specify the $x$, $y$, and $z$ coordinates of the new current normal. The initial value of the current normal is the unit vector, (0, 0, 1).

C Specification

 void glNormal3bv( const GLbyte * v);
 void glNormal3dv( const GLdouble * v);
 void glNormal3fv( const GLfloat * v);
 void glNormal3iv( const GLint * v);
 void glNormal3sv( const GLshort * v);

Parameters

v

Specifies a pointer to an array of three elements: the $x$, $y$, and $z$ coordinates of the new current normal.

Description

The current normal is set to the given coordinates whenever glNormal is issued. Byte, short, or integer arguments are converted to floating-point format with a linear mapping that maps the most positive representable integer value to 1.0 and the most negative representable integer value to $-1.0$.

Normals specified with glNormal need not have unit length. If GL_NORMALIZE is enabled, then normals of any length specified with glNormal are normalized after transformation. If GL_RESCALE_NORMAL is enabled, normals are scaled by a scaling factor derived from the modelview matrix. GL_RESCALE_NORMAL requires that the originally specified normals were of unit length, and that the modelview matrix contain only uniform scales for proper results. To enable and disable normalization, call glEnable and glDisable with either GL_NORMALIZE or GL_RESCALE_NORMAL. Normalization is initially disabled.

Notes

The current normal can be updated at any time. In particular, glNormal can be called between a call to glBegin and the corresponding call to glEnd.

Associated Gets

glGet with argument GL_CURRENT_NORMAL

glIsEnabled with argument GL_NORMALIZE

glIsEnabled with argument GL_RESCALE_NORMAL