glXGetFBConfigAttribSGIX(3G) OpenGL Reference - GLX
NAMEglXGetFBConfigAttribSGIX - return information about a GLX frame buffer
configuraton
C SPECIFICATION
int glXGetFBConfigAttribSGIX( Display *dpy,
GLXFBConfigSGIX config,
int attribute,
int *value )
PARAMETERS
dpy Specifies the connection to the X server.
config Specifies the GLX frame buffer configuration to be queried.
attribute Specifies the attribute to be returned.
value Returns the requested value.
DESCRIPTIONglXGetFBConfigAttribSGIX sets value to the attribute value of GLX
drawables created with respect to config. glXGetFBConfigAttribSGIX
returns an error code if it fails for any reason. Otherwise, zero is
returned.
attribute is one of the following:
GLX_BUFFER_SIZE Number of bits per color buffer. If the frame
buffer configuration supports RGBA contexts then
GLX_BUFFER_SIZE is the sum of GLX_RED_SIZE,
GLX_GREEN_SIZE, GLX_BLUE_SIZE, and GLX_ALPHA_SIZE.
If the frame buffer configuration supports only
color index contexts, GLX_BUFFER_SIZE is the size
of the color indexes.
GLX_LEVEL Frame buffer level of the configuration. Level
zero is the default frame buffer. Positive levels
correspond to frame buffers that overlay the
default buffer, and negative levels correspond to
frame buffers that underlay the default buffer.
GLX_DOUBLEBUFFER True if color buffers exist in front/back pairs
that can be swapped, False otherwise.
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GLX_STEREO True if color buffers exist in left/right pairs,
False otherwise.
GLX_AUX_BUFFERS Number of auxiliary color buffers that are
available. Zero indicates that no auxiliary color
buffers exist.
GLX_RED_SIZE Number of bits of red stored in each color buffer.
Undefined if RGBA contexts are not supported by the
frame buffer configuration.
GLX_GREEN_SIZE Number of bits of green stored in each color
buffer. Undefined if RGBA contexts are not
supported by the frame buffer configuration.
GLX_BLUE_SIZE Number of bits of blue stored in each color buffer.
Undefined if RGBA contexts are not supported by the
frame buffer configuration.
GLX_ALPHA_SIZE Number of bits of alpha stored in each color
buffer. Undefined if RGBA contexts are not
supported by the frame buffer configuration.
GLX_DEPTH_SIZE Number of bits in the depth buffer.
GLX_STENCIL_SIZE Number of bits in the stencil buffer.
GLX_ACCUM_RED_SIZE Number of bits of red stored in the accumulation
buffer.
GLX_ACCUM_GREEN_SIZE Number of bits of green stored in the accumulation
buffer.
GLX_ACCUM_BLUE_SIZE Number of bits of blue stored in the accumulation
buffer.
GLX_ACCUM_ALPHA_SIZE Number of bits of alpha stored in the accumulation
buffer.
GLX_SAMPLE_BUFFERS_SGIS
Number of multisample buffers.
GLX_SAMPLES_SGIS Number of samples per pixel in multisample buffers.
GLX_X_VISUAL_TYPE_EXT Visual type of associated visual. Undefined if
there is no associated visual (i.e., if
GLX_X_RENDERABLE_SGIX is False or
GLX_DRAWABLE_TYPE_SGIX does not have the
GLX_WINDOW_BIT_SGIX bit set.)
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GLX_TRANSPARENT_TYPE_EXT
One of GLX_NONE_EXT, GLX_TRANSPARENT_RGB_EXT,
GLX_TRANSPARENT_INDEX_EXT, indicating that the
frame buffer configuration is opaque, is
transparent for particular values of red, green and
blue or is transparent for particular index values,
respectively.
GLX_TRANSPARENT_INDEX_VALUE_EXT
Integer value between 0 and the maximum frame
buffer value for indices, indicating the
transparent index value for the frame buffer
configuration. Undefined if
GLX_TRANSPARENT_TYPE_EXT is not
GLX_TRANSPARENT_INDEX_EXT.
GLX_TRANSPARENT_RED_VALUE_EXT
Integer value between 0 and the maximum frame
buffer value for red, indicating the transparent
red value for the frame buffer configuration.
Undefined if GLX_TRANSPARENT_TYPE_EXT is not
GLX_TRANSPARENT_RGB_EXT.
GLX_TRANSPARENT_GREEN_VALUE_EXT
Integer value between 0 and the maximum frame
buffer value for green, indicating the transparent
green value for the frame buffer configuration.
Undefined if GLX_TRANSPARENT_TYPE_EXT is not
GLX_TRANSPARENT_RGB_EXT.
GLX_TRANSPARENT_BLUE_VALUE_EXT
Integer value between 0 and the maximum frame
buffer value for blue, indicating the transparent
blue value for the frame buffer configuration.
Undefined if GLX_TRANSPARENT_TYPE_EXT is not
GLX_TRANSPARENT_RGB_EXT.
GLX_TRANSPARENT_ALPHA_VALUE_EXT
Currently unused.
GLX_VISUAL_CAVEAT_EXT One of GLX_NONE_EXT, GLX_SLOW_VISUAL_EXT,
GLX_NON_CONFORMANT_EXT indicating that the frame
buffer configuration has no caveats, some aspect of
the frame buffer configuration runs slower than
other frame buffer configurations, or some aspect
of the frame buffer configuration is non-confomant,
respectively.
GLX_DRAWABLE_TYPE_SGIX
Mask indicating what drawable types the frame
buffer configuration supports. Valid bits are
GLX_WINDOW_BIT_SGIX, GLX_PIXMAP_BIT_SGIX and
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GLX_PBUFFER_BIT_SGIX.
GLX_RENDER_TYPE_SGIX Mask indicating what type of GLX contexts can be
made current to the frame buffer configuration.
Valid bits are GLX_RGBA_BIT_SGIX and
GLX_COLOR_INDEX_BIT_SGIX.
GLX_X_RENDERABLE_SGIX True if drawables created with the frame buffer
configuration can be rendered to by X.
GLX_MAX_PBUFFER_WIDTH_SGIX
The maximum width that can be specified to
glXCreateGLXPbufferSGIX.
GLX_MAX_PBUFFER_HEIGHT_SGIX
The maximum height that can be specified to
glXCreateGLXPbufferSGIX.
GLX_MAX_PBUFFER_PIXELS_SGIX
The maximum number of pixels (width times height)
for a pbuffer. Note that this value may be less
than GLX_MAX_PBUFFER_WIDTH_SGIX times
GLX_MAX_PBUFFER_HEIGHT_SGIX. Also, this value is
static and assumes that no other pbuffers or X
resources are contending for the framebuffer
memory. As a result, it may not be possible to
allocate a pbuffer of the size given by
GLX_MAX_PBUFFER_PIXELS_SGIX.
GLX_OPTIMAL_PBUFFER_WIDTH_SGIX
The optimum width for a pbuffer.
GLX_OPTIMAL_PBUFFER_HEIGHT_SGIX
The optimum height for a pbuffer.
Applications should choose the frame buffer configuration that most
closely meets their requirements. Creating windows, GLX pixmaps or GLX
pixel buffers with unnecessary buffers can result in reduced rendering
performance as well as poor resource allocation.
NOTESglXGetFBConfigAttribSGIX is part of the GLX_SGIX_fbconfig extension.
glXGetFBConfigAttribSGIX is implemented as a client-side utility; it does
not require a round-trip to the X server.
GLX_SAMPLE_BUFFERS_SGIS and GLX_SAMPLES_SGIS are not valid attributes
unless the SGIS_multisample extension is supported.
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glXGetFBConfigAttribSGIX(3G) OpenGL Reference - GLX
GLX_X_VISUAL_TYPE_EXT, GLX_TRANSPARENT_TYPE_EXT,
GLX_TRANSPARENT_INDEX_VALUE_EXT, GLX_TRANSPARENT_RED_VALUE_EXT,
GLX_TRANSPARENT_GREEN_VALUE_EXT, GLX_TRANSPARENT_BLUE_VALUE_EXT, and
GLX_TRANSPARENT_ALPHA_VALUE_EXT are not valid attributes unless the
EXT_visual_info extension is supported.
GLX_VISUAL_CAVEAT_EXT is not a valid attribute unless the
EXT_visual_rating extension is supported.
ERRORS
GLX_NO_EXTENSION is returned if dpy does not support the GLX extension.
GLX_BAD_ATTRIB is returned if attribute is not a valid GLX attribute.
MACHINE DEPENDENCIES
The SGIS_multisample extension is supported only on RealityEngine,
RealityEngine2, and VTX systems and InfiniteReality systems.
SEE ALSO
glXGetConfig, glXChooseFBConfigSGIX, glXCreateGLXPixmapWithConfigSGIX,
glXCreateContextWithConfigSGIX, glXGetVisualFromFBConfigSGIX,
glXGetFBConfigFromVisualSGIX.
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