glNormalPointerEXT.3gl




Name

  glNormalPointerEXT - define a	array of normals


C Specification

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


Parameters


  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.


Description

  glNormalPointerEXT specifies the location and data format of an array of
  normals to use when rendering using the vertex array extension. 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.

Notes

  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 EXT_vertex_array extension, not
  part of the core GL command set. If "GL_EXT_vertex_array" is
  included in the string returned by glGetString, when called with argument
  GL_EXTENSIONS, extension EXT_vertex_array is supported.

Errors

  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

See Also

  glArrayElementEXT, glColorPointerEXT,	glDrawArraysEXT,
  glEdgeFlagPointerEXT,	glGetPointervEXT, glIndexPointerEXT,
  glTexCoordPointerEXT,	glVertexPointerEXT, glEnable



Introduction | Alphabetic | Specification

Last Edited: Fri Feb 24, 1995

AFV