NAME fglReadBuffer - select a color buffer source for pixels FORTRAN SPECIFICATION SUBROUTINE fglReadBuffer( INTEGER*4 mode ) PARAMETERS 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 fglReadBuffer specifies a color buffer as the source for subsequent fglReadPixels, fglCopyTexImage1D, fglCopyTexImage2D, fglCopyTexSubImage1D, fglCopyTexSubImage2D, and fglCopyPixels 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 fglReadBuffer. mode is initially GL_FRONT in single-buffered configurations, and GL_BACK in double-buffered configurations. ERRORS 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 fglReadBuffer is executed between the execution of fglBegin and the corresponding execution of fglEnd. ASSOCIATED GETS fglGet with argument GL_READ_BUFFER SEE ALSO fglCopyPixels, fglCopyTexImage1D, fglCopyTexImage2D, fglCopyTexSubImage1D, fglCopyTexSubImage2D, fglDrawBuffer, fglReadPixels