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GL
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Method GL.glDrawBuffer()
- Method
glDrawBuffer
void glDrawBuffer(int mode) - 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.
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| GL_FRONT_LEFT
| Only the front left color buffer is written.
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| GL_FRONT_RIGHT
| Only the front right color buffer is written.
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| GL_BACK_LEFT
| Only the back left color buffer is written.
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| GL_BACK_RIGHT
| Only the back right color buffer is written.
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| 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.
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| 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.
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| 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.
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| 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.
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| 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.
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| GL_AUXi
| Only auxiliary color buffer i is written.
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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
.I left
buffers, and stereoscopic contexts include both
.I left
and
.I right
buffers.
Likewise, single-buffered contexts include only
.I front
buffers, and double-buffered contexts include both
.I front
and
.I back
buffers.
The context is selected at GL initialization.
- Parameter 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 ,
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.
- Throws
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 .
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GL.glDrawArrays()