1991-2006
Silicon Graphics, Inc.
glNormalPointer
3G
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 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 format of an array of normals
to use when rendering.
type specifies the data type of each normal coordinate,
and stride specifies 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.)
If a non-zero named buffer object is bound to the GL_ARRAY_BUFFER target
(see glBindBuffer) while a normal array is
specified, pointer is treated as a byte offset into the buffer object's data store.
Also, the buffer object binding (GL_ARRAY_BUFFER_BINDING) is saved as normal vertex array
client-side state (GL_NORMAL_ARRAY_BUFFER_BINDING).
When a normal array is specified,
type, stride, and pointer are saved as client-side
state, in addition to the current vertex array buffer object binding.
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, glMultiDrawArrays, glDrawElements,
glMultiDrawElements, glDrawRangeElements, or
glArrayElement is called.
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, glDrawRangeElements,
glDrawArrays, glMultiDrawArrays, or glMultiDrawElements
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.
Normal array parameters are client-side state and are therefore 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
glGet with argument GL_NORMAL_ARRAY_BUFFER_BINDING
glGet with argument GL_ARRAY_BUFFER_BINDING
glGetPointerv with argument GL_NORMAL_ARRAY_POINTER
See Also
glArrayElement,
glBindBuffer,
glColorPointer,
glDisableClientState,
glDrawArrays,
glDrawElements,
glDrawRangeElements,
glEdgeFlagPointer,
glEnableClientState,
glFogCoordPointer,
glIndexPointer,
glInterleavedArrays,
glMultiDrawArrays,
glMultiDrawElements,
glNormal,
glPopClientAttrib,
glPushClientAttrib,
glSecondaryColorPointer,
glTexCoordPointer,
glVertexAttribPointer,
glVertexPointer
Copyright
Copyright 1991-2006
Silicon Graphics, Inc. This document is licensed under the SGI
Free Software B License. For details, see
http://oss.sgi.com/projects/FreeB/.