GLXGETFBCONFIGATTRIBSGIX(3gl)GLXGETFBCONFIGATTRIBSGIX(3gl)NAMEglXGetFBConfigAttribSGIX - return information about GLX fbconfigs
C SPECIFICATION
int glXGetFBConfigAttribSGIX( Display *dpy,
GLXFBConfigSGIX config,
int attrib,
int *value )
PARAMETERS
dpy Specifies the connection to the X server.
config Specifies the configuration to be queried. It is a pointer to
an XVisualInfo structure, not a visual ID or a pointer to a
Visual.
attrib Specifies the configuration attribute to be returned.
value Returns the requested value.
DESCRIPTIONglXGetFBConfigAttribSGIX sets value to the attrib value from the speci‐
fied config. glXGetFBConfigAttribSGIX returns an error code if it
fails for any reason. Otherwise, zero is returned.
attrib is one of the following:
GLX_BUFFER_SIZE Number of bits per color buffer. For RGBA visu‐
als, GLX_BUFFER_SIZE is the sum of GLX_RED_SIZE,
GLX_GREEN_SIZE, GLX_BLUE_SIZE, and
GLX_ALPHA_SIZE. For color index visuals,
GLX_BUFFER_SIZE is the size of the color indexes.
GLX_LEVEL Frame buffer level of the visual. Level zero is
the default frame buffer. Positive levels corre‐
spond 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.
GLX_STEREO True if color buffers exist in left/right pairs,
False otherwise.
GLX_AUX_BUFFERS Number of auxiliary color buffers that are avail‐
able. Zero indicates that no auxiliary color
buffers exist.
GLX_RED_SIZE Number of bits of red stored in each color buf‐
fer.
GLX_GREEN_SIZE Number of bits of green stored in each color buf‐
fer.
GLX_BLUE_SIZE Number of bits of blue stored in each color buf‐
fer.
GLX_ALPHA_SIZE Number of bits of alpha stored in each color buf‐
fer.
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 accumula‐
tion 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 accumula‐
tion buffer. GLX_SAMPLE_BUFFERS_SGIS Number of
multisample buffers.
GLX_SAMPLES_SGIS Number of samples stored in each multisample buf‐
fer.
GLX_X_VISUAL_TYPE_EXT X visual type of the associated visual.
GLX_TRANSPARENT_TYPE_EXT
Transparent type - should be GLX_NONE_EXT,
GLX_TRANSPARENT_RGB_EXT or GLX_TRANSPAR‐
ENT_INDEX_EXT.
GLX_TRANSPARENT_INDEX_VALUE_EXT
Transparent index value.
GLX_TRANSPARENT_RED_VALUE_EXT
Transparent red value.
GLX_TRANSPARENT_GREEN_VALUE_EXT
Transparent green value.
GLX_TRANSPARENT_BLUE_VALUE_EXT
Transparent blue value.
GLX_TRANSPARENT_ALPHA_VALUE_EXT
Transparent alpha value.
GLX_VISUAL_CAVEAT_EXT Description of the visual - should be
GLX_NONE_EXT or GLX_SLOW_VISUAL_EXT.
GLX_DRAWABLE_TYPE_SGIX
Mask indicating which GLX drawables are sup‐
ported. Valid bits are GLX_WINDOW_BIT_SGIX,
GLX_PIXMAP_BIT_SGIX and GLX_PBUFFER_BIT_SGIX.
GLX_RENDER_TYPE_SGIX Mask indicating which OpenGL rendering modes are
supported. Valid bits are GLX_RGBA_BIT_SGIX,
GLX_COLOR_INDEX_SGIX.
GLX_X_RENDERABLE_SGIX True if X can render to drawable.
GLX_FBCONFIG_ID_SGIX X id of the GLXFBConfigSGIX.
GLX_VISUAL_ID_EXT Visual id of the GLXFBConfigSGIX.
GLX_MAX_PBUFFER_WIDTH_SGIX
Maximum width of the pbuffer supported.
GLX_MAX_PBUFFER_HEIGHT_SGIX
Maximum height of the pbuffer supported.
GLX_MAX_PBUFFER_PIXELS_SGIX
Maximum size of the pbuffer supported
GLX_OPTIMAL_PBUFFER_WIDTH_SGIX
Best width to use when creating pbuffer. Zero
indicates that all widths are equally good.
GLX_OPTIMAL_PBUFFER_HEIGHT_SGIX
Best height to use when creating pbuffer. Zero
indicates that all widths are equally good.
GLXFBConfigSGIX has an associated X visual if and only if the GLX_DRAW‐
ABLE_TYPE_SGIX has the GLX_WINDOW_BIT_SGIX or GLX_PIXMAP_BIT_SGIX is
set.
Although a GLX implementation can export many config that support GL
rendering, it must support at least one RGBA config. This config must
have at least one color buffer, a stencil buffer of at least 1 bit, a
depth buffer of at least 12 bits, and an accumulation buffer. Alpha
bitplanes are optional in this config. However, its color buffer size
must be as great as that of the deepest TrueColor, DirectColor, Pseudo‐
Color, or StaticColor visual supported on level zero, and it must
itself be made available on level zero.
Applications are best written to select the config that most closely
meets their requirements. Creating windows, GLX pixmaps or GLX
pbuffers with unnecessary buffers can result in reduced rendering per‐
formance as well as poor resource allocation.
NOTES
GLX_SGIX_fbconfig extension should be supported for this function to be
valid.
This function is superseded by glXGetFBConfigAttrib, which is part of
GLX Version 1.3 command set. glXGetFBConfigAttribSGIX is supported only
for backward compatibility.
ERRORS
GLX_NO_EXTENSION is returned if dpy does not support the GLX extension.
GLX_BAD_SCREEN is returned if the screen of vis does not correspond to
a screen.
GLX_BAD_ATTRIBUTE is returned if attrib is not a valid GLX attribute.
SEE ALSO
glXChooseVisual, glXGetConfig, glXCreateContextWithConfigSGIX, glXCre‐
ateGLXPixmapWithConfigSGIX, glXChooseFBConfigSGIX, glXGetFBCon‐
figFromVisualSGIX, glXGetFBConfigFromVisualSGIX, glXCreateGLXPbufferS‐
GIX, glXDestroyGLXPbufferSGIX, glXQueryGLXPbufferSGIX
21 May 97 GLXGETFBCONFIGATTRIBSGIX(3gl)