glCopyTexImage1DEXT(3G)	       OpenGL Reference	       glCopyTexImage1DEXT(3G)



NAME
     glCopyTexImage1DEXT - copy	pixels into a 1D texture image


C SPECIFICATION
     void glCopyTexImage1DEXT( GLenum target,
			       GLint level,
			       GLenum internalformat,
			       GLint x,
			       GLint y,
			       GLsizei width,
			       GLint border )


PARAMETERS
     target	     The target	texture.  Must be GL_TEXTURE_1D

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

     internalformat  The internal storage format of the	texture	image.	Must
		     be	one of the following symbolic constants:  GL_ALPHA,
		     GL_ALPHA4_EXT, GL_ALPHA8_EXT, GL_ALPHA12_EXT,
		     GL_ALPHA16_EXT, GL_LUMINANCE, GL_LUMINANCE4_EXT,
		     GL_LUMINANCE8_EXT,	GL_LUMINANCE12_EXT,
		     GL_LUMINANCE16_EXT, GL_LUMINANCE_ALPHA,
		     GL_LUMINANCE4_ALPHA4_EXT, GL_LUMINANCE6_ALPHA2_EXT,
		     GL_LUMINANCE8_ALPHA8_EXT, GL_LUMINANCE12_ALPHA4_EXT,
		     GL_LUMINANCE12_ALPHA12_EXT, GL_LUMINANCE16_ALPHA16_EXT,
		     GL_INTENSITY_EXT, GL_INTENSITY4_EXT, GL_INTENSITY8_EXT,
		     GL_INTENSITY12_EXT, GL_INTENSITY16_EXT, GL_RGB,
		     GL_RGB2_EXT, GL_RGB4_EXT, GL_RGB5_EXT, GL_RGB8_EXT,
		     GL_RGB10_EXT, GL_RGB12_EXT, GL_RGB16_EXT, GL_RGBA,
		     GL_RGBA2_EXT, GL_RGBA4_EXT, GL_RGB5_A1_EXT, GL_RGBA8_EXT,
		     GL_RGB10_A2_EXT, GL_RGBA12_EXT, GL_RGBA16_EXT.  (Note
		     that the values 1,	2, 3, and 4, which are accepted	by
		     glTexImage1D, are not accepted by glCopyTexImage1DEXT.)

     x		     The x coordinate of the lower-left	corner of the pixel
		     rectangle to be transferred to the	texture	array.

     y		     The y coordinate of the lower-left	corner of the pixel
		     rectangle to be transferred to the	texture	array.

     width	     The width of the texture image.

     border	     The border	width of the texture.  Must be 0 or 1.

DESCRIPTION
     glCopyTexImage1DEXT defines a one-dimensional texture image with pixels
     from the current GL_READ_BUFFER (rather than from main memory, as is the
     case for glTexImage1D).



									Page 1






glCopyTexImage1DEXT(3G)	       OpenGL Reference	       glCopyTexImage1DEXT(3G)



     The screen-aligned	pixel rectangle	with lower-left	corner at (x, y)
     having width width+2*border and height 1 is used to define	the texture
     array at the mipmap level specified by level.  The	internal format	of the
     texture array is selected by internalformat.

     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 screen	coordinates correspond to
     lower i texture coordinates, and lower y screen coordinates correspond to
     lower j 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
     glCopyTexImage1DEXT is part of the	EXT_copy_texture extension.  See
     glIntro for more information about	using extensions.

ERRORS
     GL_INVALID_ENUM is	generated when target is not one of the	allowable
     values.

     GL_INVALID_VALUE is generated if level is less than zero or greater than
     log2(max),	where max is the returned value	of GL_MAX_TEXTURE_SIZE.

     GL_TEXTURE_TOO_LARGE_EXT is generated if the specified image is too
     large.

     GL_INVALID_VALUE is generated if width is less than zero, greater than
     2+GL_MAX_TEXTURE_SIZE, or when width cannot be represented	as 2k+2border
     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 glCopyTexImage1DEXT is executed
     between the execution of glBegin and the corresponding execution of
     glEnd.

ASSOCIATED GETS
     glGetTexImage






									Page 2






glCopyTexImage1DEXT(3G)	       OpenGL Reference	       glCopyTexImage1DEXT(3G)



MACHINE	DEPENDENCIES
     glCopyTexImage1DEXT is not	supported on RealityEngine, RealityEngine2,
     and VTX systems.

     On	InfiniteReality	systems, the width of the image	to be transferred to
     texture memory must be a multiple of 8.  This constraint will be lifted
     in	a future release, though transfers that	are a multiple of 8 in length
     will have somewhat	higher performance than	other transfers.

     Texture borders are not supported on InfiniteReality systems.  They will
     be	supported in a future release, however,	they will require large
     amounts of	texture	memory.	 Whenever possible, applications should	use
     borderless	textures and GL_CLAMP_TO_EDGE_SGIS wrap	mode.


SEE ALSO
     glTexImage1D, glCopyTexSubImage1DEXT, glCopyPixels.






































									Page 3