trusty (3) glDrawBuffer.3G.gz

NAME

       glDrawBuffer - specify which color buffers are to be drawn into

C SPECIFICATION

       void glDrawBuffer(GLenum mode);

PARAMETERS

       mode
           Specifies up to four color buffers to be drawn into. Symbolic constants GL_NONE, GL_FRONT_LEFT,
           GL_FRONT_RIGHT, GL_BACK_LEFT, GL_BACK_RIGHT, GL_FRONT, GL_BACK, GL_LEFT, GL_RIGHT, and
           GL_FRONT_AND_BACK are accepted. The initial value is GL_FRONT for single-buffered contexts, and
           GL_BACK for double-buffered contexts.

DESCRIPTION

       When colors are written to the frame buffer, they are written into the color buffers specified by
       glDrawBuffer. The specifications are as follows:

       GL_NONE
           No color buffers are written.

       GL_FRONT_LEFT
           Only the front left color buffer is written.

       GL_FRONT_RIGHT
           Only the front right color buffer is written.

       GL_BACK_LEFT
           Only the back left color buffer is written.

       GL_BACK_RIGHT
           Only the back right color buffer is written.

       GL_FRONT
           Only the front left and front right color buffers are written. If there is no front right color
           buffer, only the front left color buffer is written.

       GL_BACK
           Only the back left and back right color buffers are written. If there is no back right color buffer,
           only the back left color buffer is written.

       GL_LEFT
           Only the front left and back left color buffers are written. If there is no back left color buffer,
           only the front left color buffer is written.

       GL_RIGHT
           Only the front right and back right color buffers are written. If there is no back right color
           buffer, only the front right color buffer is written.

       GL_FRONT_AND_BACK
           All the front and back color buffers (front left, front right, back left, back right) are written. If
           there are no back color buffers, only the front left and front right color buffers are written. If
           there are no right color buffers, only the front left and back left color buffers are written. If
           there are no right or back color buffers, only the front left color buffer is written.

       If more than one color buffer is selected for drawing, then blending or logical operations are computed
       and applied independently for each color buffer and can produce different results in each buffer.

       Monoscopic contexts include only left buffers, and stereoscopic contexts include both left and right
       buffers. Likewise, single-buffered contexts include only front buffers, and double-buffered contexts
       include both front and back buffers. The context is selected at GL initialization.

ERRORS

       GL_INVALID_ENUM is generated if mode is not an accepted value.

       GL_INVALID_OPERATION is generated if none of the buffers indicated by mode exists.

ASSOCIATED GETS

       glGet() with argument GL_DRAW_BUFFER

SEE ALSO

       glBlendFunc(), glColorMask(), glDrawBuffers(), glLogicOp(), glReadBuffer()

COPYRIGHT

       Copyright © 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B
       License. For details, see http://oss.sgi.com/projects/FreeB/.

AUTHORS

       opengl.org