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GLNORMALPOINTER(3G)                                                                      GLNORMALPOINTER(3G)



NAME
       glNormalPointer - define an array of normals


C SPECIFICATION
       void glNormalPointer( GLenum type,
                             GLsizei stride,
                             const GLvoid *pointer )


PARAMETERS
       type     Specifies  the  data  type  of  each  coordinate  in the array.  Symbolic constants GL_BYTE,
                GL_SHORT, GL_INT, GL_FLOAT, and GL_DOUBLE are accepted. The initial value is GL_FLOAT.

       stride   Specifies the byte offset between consecutive normals. If stride is 0- the initial value-the
                normals are understood to be tightly packed in the array.  The initial value is 0.

       pointer  Specifies  a  pointer to the first coordinate of the first normal in the array.  The initial
                value is 0.

DESCRIPTION
       glNormalPointer specifies the location and data  of an array of normals to use when rendering.   type
       specifies the data type of the normal coordinates and stride 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
       glInterleavedArrays.)  When a normal array is specified, type,  stride,  and  pointer  are  saved  as
       client-side state.

       To  enable  and  disable the normal array, call glEnableClientState and glDisableClientState with the
       argument GL_NORMAL_ARRAY. If enabled, the normal array is used when glDrawArrays, glDrawElements,  or
       glArrayElement is called.

       Use  glDrawArrays to construct a sequence of primitives (all of the same type) from prespecified ver-tex vertex
       tex and vertex attribute arrays.  Use glArrayElement to specify primitives by indexing  vertices  and
       vertex  attributes  and glDrawElements to construct a sequence of primitives by indexing vertices and
       vertex attributes.

NOTES
       glNormalPointer is available only if the GL version is 1.1 or greater.

       The normal array is initially disabled and isn't accessed  when  glArrayElement,  glDrawElements,  or
       glDrawArrays is called.

       Execution of glNormalPointer is not allowed between glBegin and the corresponding glEnd, but an error
       may or may not be generated. If an error is not generated, the operation is undefined.

       glNormalPointer is typically implemented on the client side.

       Since the normal array  parameters  are  client-side  state,  they  are  not  saved  or  restored  by
       glPushAttrib and glPopAttrib.  Use glPushClientAttrib and glPopClientAttrib instead.

ERRORS
       GL_INVALID_ENUM is generated if type is not an accepted value.

       GL_INVALID_VALUE is generated if stride is negative.

ASSOCIATED GETS
       glIsEnabled with argument GL_NORMAL_ARRAY
       glGet with argument GL_NORMAL_ARRAY_TYPE
       glGet with argument GL_NORMAL_ARRAY_STRIDE
       glGetPointerv with argument GL_NORMAL_ARRAY_POINTER

SEE ALSO
       glArrayElement(3G),    glColorPointer(3G),   glDrawArrays(3G),   glDrawElements(3G),   glEdgeFlagPointer(3G),   glEnable(3G),
       glGetPointerv(3G),   glIndexPointer(3G),    glInterleavedArrays(3G),    glPopClientAttrib(3G),    glPushClientAttrib(3G),
       glTexCoordPointer(3G), glVertexPointer(3G)




                                                                                         GLNORMALPOINTER(3G)