GLNORMALPOINTER() MachTen Programmer’s Manual GLNORMALPOINTER()

NAME
glNormalPointer - define an array of normals

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

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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.

pointer Specifies a pointer to the first coordinate of
the first normal 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 ver-
texes 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 glInter-
leavedArrays.) When a normal array is specified, type,
stride, and pointer are saved as client-side state.

To enable and disable the normal array, call glEnable-
ClientState 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 vertex and vertex
attribute arrays. Use glArrayElement to specify primi-
tives 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 glArrayElement, glDrawElements, or glDrawArrays is
called.

Execution of glNormalPointer is not allowed between glBe-
gin and the corresponding glEnd, but an error may or may
not be generated. If an error is not generated, the opera-
tion 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, glColorPointer, glDrawArrays, glDrawEle-
ments, glEdgeFlagPointer, glEnable, glGetPointerv, glInd-
exPointer, glInterleavedArrays, glPopClientAttrib, glPush-
ClientAttrib, glTexCoordPointer, glVertexPointer

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