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OpenGL 1.1 for AIX: Reference Manual

glNormalPointerEXT Subroutine


Defines an array of normals.


OpenGL C bindings library: libGL.a

C Syntax

void glNormalPointerEXT(GLenum type, 
      GLsizei stride, 
      GLsizei count, 
      const GLvoid *pointer)


type Specifies the the data type of each coordinate in the array. Symbolic constants GL_BYTE, GL_SHORT, GL_INT, GL_FLOAT, or GL_DOUBLE_EXT are accepted.
stride Specifies the byte offset between consecutive normals.
count Specifies the number of normals, counting from the first, that are static.
pointer Specifies a pointer to the first coordinate of the first normal in the array.


glNormalPointerEXT 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.) count indicates the number of array elements (counting from the first) that are static. Static elements may be modified by the application, but once they are modified, the application must explicitly respecify the array before using it for any rendering. When a normal array is specified, type, stride, count and pointer are saved as client-side state, and static array elements may be cached by the implementation.

The normal array is enabled and disabled using glEnable and glDisable with the argument GL_NORMAL_ARRAY_EXT. If enabled, the normal array is used when glDrawArraysEXT or glArrayElementEXT is called.

Use glDrawArraysEXT to define a sequence of primitives (all of the same type) from pre-specified vertex and vertex attribute arrays. Use glArrayElementEXT to specify primitives by indexing vertexes and vertex attributes.


Non-static array elements are not accessed until glArrayElementEXT or glDrawArraysEXT is executed.

By default the normal array is disabled and it won't be accessed when glArrayElementEXT or glDrawArraysEXT is called.

Although, it is not an error to call glNormalPointerEXT between the execution of glBegin and the corresponding execution of glEnd, the results are undefined.

glNormalPointerEXT will typically be implemented on the client side with no protocol.

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

glNormalPointerEXT commands are not entered into display lists.

glNormalPointerEXT is part of the _extname(EXT_vertex_array) extension, not part of the core GL command set. If _extstring(EXT_vertex_array) is included in the string returned by glGetString, when called with argument GL_EXTENSIONS, extension _extname(EXT_vertex_array) is supported.


GL_INVALID_ENUM is generated if type is not an accepted value.

GL_INVALID_VALUE is generated if stride or count is negative.

Associated Gets

glIsEnabled with argument GL_NORMAL_ARRAY_EXT

glGet with argument GL_NORMAL_ARRAY_TYPE_EXT

glGet with argument GL_NORMAL_ARRAY_STRIDE_EXT

glGet with argument GL_NORMAL_ARRAY_COUNT_EXT

glGetPointervEXT with argument GL_NORMAL_ARRAY_POINTER_EXT


/usr/include/GL/glext.h Contains extensions to C language constants, variable type definitions, and ANSI function prototypes for OpenGL.

Related Information

The glArrayElementEXT subroutine, glColorPointerEXT subroutine, glDrawArraysEXT subroutine, glEdgeFlagPointerEXT subroutine, glGetPointervEXT subroutine, glIndexPointerEXT subroutine, glTexCoordPointerEXT subroutine, glVertexPointerEXT subroutine.

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