glReadBuffer(3G)	       OpenGL Reference		      glReadBuffer(3G)

NAME    [Toc]    [Back]

     glReadBuffer - select a color buffer source for pixels

C SPECIFICATION    [Toc]    [Back]

     void glReadBuffer(	GLenum mode )

PARAMETERS    [Toc]    [Back]

     mode  Specifies a color buffer.  Accepted values are GL_FRONT_LEFT,
	   GL_FRONT_RIGHT, GL_BACK_LEFT, GL_BACK_RIGHT,	GL_FRONT, GL_BACK,
	   GL_LEFT, GL_RIGHT, and GL_AUXi, where i is between 0	and
	   GL_AUX_BUFFERS -1.

DESCRIPTION    [Toc]    [Back]

     glReadBuffer specifies a color buffer as the source for subsequent
     glReadPixels, glCopyTexImage1D, glCopyTexImage2D, glCopyTexSubImage1D,
     glCopyTexSubImage2D, glCopyTexSubImage3D, and glCopyPixels	commands. mode
     accepts one of twelve or more predefined values.  (GL_AUX0	through
     GL_AUX3 are always	defined.)  In a	fully configured system, GL_FRONT,
     GL_LEFT, and GL_FRONT_LEFT	all name the front left	buffer,	GL_FRONT_RIGHT
     and GL_RIGHT name the front right buffer, and GL_BACK_LEFT	and GL_BACK
     name the back left	buffer.

     Nonstereo double-buffered configurations have only	a front	left and a
     back left buffer.	Single-buffered	configurations have a front left and a
     front right buffer	if stereo, and only a front left buffer	if nonstereo.
     It	is an error to specify a nonexistent buffer to glReadBuffer.

     mode is initially GL_FRONT	in single-buffered configurations, and GL_BACK
     in	double-buffered	configurations.

ERRORS    [Toc]    [Back]

     GL_INVALID_ENUM is	generated if mode is not one of	the twelve (or more)
     accepted values.

     GL_INVALID_OPERATION is generated if mode specifies a buffer that does
     not exist.

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

ASSOCIATED GETS    [Toc]    [Back]

     glGet with	argument GL_READ_BUFFER

SEE ALSO    [Toc]    [Back]

     glCopyPixels, glCopyTexImage1D, glCopyTexImage2D, glCopyTexSubImage1D,
     glCopyTexSubImage2D, glCopyTexSubImage3D, glDrawBuffer, glReadPixels


									PPPPaaaaggggeeee 1111