NAME

glNormalPointer - define an array of normals

C SPECIFICATION

void ggllNNoorrmmaallPPooiinntteerr( GLenum _t_y_p_e,
                      GLsizei _s_t_r_i_d_e,
                      const GLvoid _*_p_t_r )

delim $$

PARAMETERS

_t_y_p_e
Specifies the data type of each coordinate in the array. Symbolic constants GGLL__BBYYTTEE, GGLL__SSHHOORRTT, GGLL__IINNTT, GGLL__FFLLOOAATT, and GGLL__DDOOUUBBLLEE are accepted. The initial value is GGLL__FFLLOOAATT.
_s_t_r_i_d_e
Specifies the byte offset between consecutive normals. If _s_t_r_i_d_e is 0- the initial value-the normals are understood to be tightly packed in the array. The initial value is 0.
_p_t_r
Specifies a pointer to the first coordinate of the first normal in the array. The initial value is 0.

DESCRIPTION

ggllNNoorrmmaallPPooiinntteerr specifies the location and data of an array of normals to use when rendering. _t_y_p_e specifies the data type of the normal coordinates and _s_t_r_i_d_e gives the byte stride from one normal to the next, allowing vertices and attributes to be packed into a single array or stored in separate arrays. (Single-array storage may be more efficient on some implementations; see ggllIInntteerrlleeaavveeddAArrrraayyss.) When a normal array is specified, _t_y_p_e, _s_t_r_i_d_e, and _p_t_r are saved as client-side state.

To enable and disable the normal array, call ggllEEnnaabblleeCClliieennttSSttaattee and ggllDDiissaabblleeCClliieennttSSttaattee with the argument GGLL__NNOORRMMAALL__AARRRRAAYY. If enabled, the normal array is used when ggllDDrraawwAArrrraayyss, ggllDDrraawwEElleemmeennttss, or ggllAArrrraayyEElleemmeenntt is called.

Use ggllDDrraawwAArrrraayyss to construct a sequence of primitives (all of the same type) from prespecified vertex and vertex attribute arrays. Use ggllAArrrraayyEElleemmeenntt to specify primitives by indexing vertices and vertex attributes and ggllDDrraawwEElleemmeennttss to construct a sequence of primitives by indexing vertices and vertex attributes.

NOTES

ggllNNoorrmmaallPPooiinntteerr is available only if the GL version is 1.1 or greater.

The normal array is initially disabled and isn't accessed when ggllAArrrraayyEElleemmeenntt, ggllDDrraawwEElleemmeennttss, or ggllDDrraawwAArrrraayyss is called.

Execution of ggllNNoorrmmaallPPooiinntteerr is not allowed between ggllBBeeggiinn and the corresponding ggllEEnndd, but an error may or may not be generated. If an error is not generated, the operation is undefined.

ggllNNoorrmmaallPPooiinntteerr is typically implemented on the client side.

Since the normal array parameters are client-side state, they are not saved or restored by ggllPPuusshhAAttttrriibb and ggllPPooppAAttttrriibb. Use ggllPPuusshhCClliieennttAAttttrriibb and ggllPPooppCClliieennttAAttttrriibb instead.

ERRORS

GGLL__IINNVVAALLIIDD__EENNUUMM is generated if _t_y_p_e is not an accepted value.

GGLL__IINNVVAALLIIDD__VVAALLUUEE is generated if _s_t_r_i_d_e is negative.

ASSOCIATED GETS

ggllIIssEEnnaabblleedd with argument GGLL__NNOORRMMAALL__AARRRRAAYY
ggllGGeett with argument GGLL__NNOORRMMAALL__AARRRRAAYY__TTYYPPEE
ggllGGeett with argument GGLL__NNOORRMMAALL__AARRRRAAYY__SSTTRRIIDDEE
ggllGGeettPPooiinntteerrvv with argument GGLL__NNOORRMMAALL__AARRRRAAYY__PPOOIINNTTEERR

SEE ALSO

ggllAArrrraayyEElleemmeenntt((33GG)), ggllCCoolloorrPPooiinntteerr((33GG)), ggllDDrraawwAArrrraayyss((33GG)), ggllDDrraawwEElleemmeennttss((33GG)), ggllEEddggeeFFllaaggPPooiinntteerr((33GG)), ggllEEnnaabbllee((33GG)), ggllGGeettPPooiinntteerrvv((33GG)), ggllIInnddeexxPPooiinntteerr((33GG)), ggllIInntteerrlleeaavveeddAArrrraayyss((33GG)), ggllPPooppCClliieennttAAttttrriibb((33GG)), ggllPPuusshhCClliieennttAAttttrriibb((33GG)), ggllTTeexxCCoooorrddPPooiinntteerr((33GG)), ggllVVeerrtteexxPPooiinntteerr((33GG))