NAME
	  glCopyTexImage2D - copy pixels into a	2D texture image


     C SPECIFICATION
	  void glCopyTexImage2D( GLenum	target,
				 GLint level,
				 GLenum	internalFormat,
				 GLint x,
				 GLint y,
				 GLsizei width,
				 GLsizei height,
				 GLint border )


     PARAMETERS
	  target	  Specifies the	target texture.	 Must be
			  GL_TEXTURE_2D.

	  level		  Specifies the	level-of-detail	number.	 Level
			  0 is the base	image level.  Level n is the
			  nth mipmap reduction image.

	  internalFormat  Specifies the	internal format	of the
			  texture.  Must be one	of the following
			  symbolic constants:  GL_ALPHA, GL_ALPHA4,
			  GL_ALPHA8, GL_ALPHA12, GL_ALPHA16,
			  GL_LUMINANCE,	GL_LUMINANCE4, GL_LUMINANCE8,
			  GL_LUMINANCE12, GL_LUMINANCE16,
			  GL_LUMINANCE_ALPHA, GL_LUMINANCE4_ALPHA4,
			  GL_LUMINANCE6_ALPHA2,	GL_LUMINANCE8_ALPHA8,
			  GL_LUMINANCE12_ALPHA4,
			  GL_LUMINANCE12_ALPHA12,
			  GL_LUMINANCE16_ALPHA16, GL_INTENSITY,
			  GL_INTENSITY4, GL_INTENSITY8,
			  GL_INTENSITY12, GL_INTENSITY16, GL_RGB,
			  GL_R3_G3_B2, GL_RGB4,	GL_RGB5, GL_RGB8,
			  GL_RGB10, GL_RGB12, GL_RGB16,	GL_RGBA,
			  GL_RGBA2, GL_RGBA4, GL_RGB5_A1, GL_RGBA8,
			  GL_RGB10_A2, GL_RGBA12, or GL_RGBA16.

	  x, y		  Specify the window coordinates of the	lower
			  left corner of the rectangular region	of
			  pixels to be copied.

	  width		  Specifies the	width of the texture image.
			  Must be 0 or 2**n + 2*border for some
			  integer n.

	  height	  Specifies the	height of the texture image.
			  Must be 0 or 2**m + 2*border for some
			  integer m.

	  border	  Specifies the	width of the border.  Must be
			  either 0 or 1.

     DESCRIPTION
	  glCopyTexImage2D defines a two-dimensional texture image
	  with pixels from the current GL_READ_BUFFER.

	  The screen-aligned pixel rectangle with lower	left corner at
	  (x, y) and with a width of width + 2 * border	and a height
	  of height + 2	* border defines the texture array at the
	  mipmap level specified by level.  internalFormat specifies
	  the internal format of the texture array.

	  The pixels in	the rectangle are processed exactly as if
	  glCopyPixels had been	called,	but the	process	stops just
	  before final conversion.  At this point all pixel component
	  values are clamped to	the range [0,1]	and then converted to
	  the texture's	internal format	for storage in the texel
	  array.

	  Pixel	ordering is such that lower x and y screen coordinates
	  correspond to	lower s	and t texture coordinates.

	  If any of the	pixels within the specified rectangle of the
	  current GL_READ_BUFFER are outside the window	associated
	  with the current rendering context, then the values obtained
	  for those pixels are undefined.

     NOTES
	  glCopyTexImage2D is available	only if	the GL version is 1.1
	  or greater.

	  Texturing has	no effect in color index mode.

	  1, 2,	3, and 4 are not accepted values for internalFormat.

	  An image with	height or width	of 0 indicates a NULL texture.

     ERRORS
	  GL_INVALID_ENUM is generated if target is not	GL_TEXTURE_2D.

	  GL_INVALID_VALUE is generated	if level is less than 0.

	  GL_INVALID_VALUE may be generated if level is	greater	than
	  log max, where max is	the returned value of
	  GL_MAX_TEXTURE_SIZE.

	  GL_INVALID_VALUE is generated	if width or height is less
	  than 0, greater than 2 + GL_MAX_TEXTURE_SIZE,	or if width or
	  height cannot	be represented as 2**k + 2 * border for	some
	  integer k.

	  GL_INVALID_VALUE is generated	if border is not 0 or 1.

	  GL_INVALID_VALUE is generated	if internalFormat is not one
	  of the allowable values.

	  GL_INVALID_OPERATION is generated if glCopyTexImage2D	is
	  executed between the execution of glBegin and	the
	  corresponding	execution of glEnd.

     ASSOCIATED	GETS
	  glGetTexImage
	  glIsEnabled with argument GL_TEXTURE_2D

     SEE ALSO
	  glCopyPixels,	glCopyTexImage1D, glCopyTexSubImage1D,
	  glCopyTexSubImage2D, glPixelStore, glPixelTransfer,
	  glTexEnv, glTexGen, glTexImage1D, glTexImage2D,
	  glTexSubImage1D, glTexSubImage2D,
	  glTexParameter