GLNORMALPOINTER(3gl)GLNORMALPOINTER(3gl)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. Sym‐
bolic 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.
pointer Specifies a pointer to the first coordinate of the first nor‐
mal in the array.
DESCRIPTION
glNormalPointer specifies the location and data format 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 vertexes 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 glArrayEle‐
ment is called.
Use glDrawArrays to construct a sequence of primitives (all of the same
type) from prespecified vertex and vertex attribute arrays. Use glAr‐
rayElement to specify primitives by indexing vertexes and vertex
attributes and glDrawElements to construct a sequence of primitives by
indexing vertexes 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 glAr‐
rayElement, 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 glPushClientAt‐
trib 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, glColorPointer, glDrawArrays, glDrawElements, glEdge‐
FlagPointer, glEnable, glGetPointerv, glIndexPointer, glInterleavedAr‐
rays, glPopClientAttrib, glPushClientAttrib, glTexCoordPointer, glVert‐
exPointer
15 Mar 97 GLNORMALPOINTER(3gl)