glDrawBuffer(3G)glDrawBuffer(3G)NAMEglDrawBuffer - specify which color buffers are to be drawn into
SYNOPSIS
void glDrawBuffer(
GLenum mode );
PARAMETERS
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, GL_FRONT_AND_BACK, and GL_AUXi,
where i is between 0 and ``GL_AUX_BUFFERS'' -1, are accepted
(GL_AUX_BUFFERS is not the upper limit; use glGet to query the number
of available aux buffers.) 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: No color buffers are written. Only the front left color buf‐
fer is written. Only the front right color buffer is written. Only
the back left color buffer is written. Only the back right color buf‐
fer is written. 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. Only the back left and back right color buf‐
fers are written. If there is no back right color buffer, only the back
left color buffer is written. 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. Only the front right and back
right color buffers are written. If there is no back right color buf‐
fer, only the front right color buffer is written. 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 buf‐
fers, 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. Only auxiliary color buffer i 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 con‐
texts 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 ini‐
tialization.
NOTES
It is always the case that GL_AUXi = GL_AUX0 + i.
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.
GL_INVALID_OPERATION is generated if glDrawBuffer() is executed between
the execution of glBegin() and the corresponding execution of glEnd().
ASSOCIATED GETSglGet() with argument GL_DRAW_BUFFER
glGet() with argument GL_AUX_BUFFERS
SEE ALSOglBlendFunc(3), glColorMask(3), glIndexMask(3), glLogicOp(3), glRead‐
Buffer
glDrawBuffer(3G)