glXGetFBConfigAttrib(3G) OpenGL Reference - GLX glXGetFBConfigAttrib(3G)NAME
glXGetFBConfigAttrib - return information about a GLX frame buffer
configuraton
C SPECIFICATION
int glXGetFBConfigAttrib( Display *dpy,
GLXFBConfig 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.
DESCRIPTION
glXGetFBConfigAttrib sets value to the attribute value of GLX drawables
created with respect to config. glXGetFBConfigAttrib returns an error
code if it fails for any reason. Otherwise, Success is returned.
attribute is one of the following:
GLX_FBCONFIG_ID XID of the given GLXFBConfig.
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 underlie 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.
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glXGetFBConfigAttrib(3G) OpenGL Reference - GLX glXGetFBConfigAttrib(3G)
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_RENDER_TYPE Mask indicating what type of GLX contexts can be
made current to the frame buffer configuration.
Valid bits are GLX_RGBA_BIT and
GLX_COLOR_INDEX_BIT.
GLX_DRAWABLE_TYPE Mask indicating what drawable types the frame
buffer configuration supports. Valid bits are
GLX_WINDOW_BIT, GLX_PIXMAP_BIT, and
GLX_PBUFFER_BIT.
GLX_X_RENDERABLE True if drawables created with the frame buffer
configuration can be rendered to by X.
GLX_VISUAL_ID XID of the corresponding visual, or zero if there
is no associated visual (i.e., if GLX_X_RENDERABLE
is False or GLX_DRAWABLE_TYPE does not have the
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glXGetFBConfigAttrib(3G) OpenGL Reference - GLX glXGetFBConfigAttrib(3G)
GLX_WINDOW_BIT bit set.)
GLX_X_VISUAL_TYPE Visual type of associated visual. The returned
value will be one of: GLX_TRUE_COLOR,
GLX_DIRECT_COLOR, GLX_PSEUDO_COLOR,
GLX_STATIC_COLOR, GLX_GRAY_SCALE, GLX_STATIC_GRAY,
or GLX_NONE, if there is no associated visual
(i.e., if GLX_X_RENDERABLE is False or
GLX_DRAWABLE_TYPE does not have the GLX_WINDOW_BIT
bit set.)
GLX_CONFIG_CAVEAT One of GLX_NONE, GLX_SLOW_CONFIG, or
GLX_NON_CONFORMANT_CONFIG, 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
nonconformant, respectively.
GLX_TRANSPARENT_TYPE One of GLX_NONE, GLX_TRANSPARENT_RGB,
GLX_TRANSPARENT_INDEX, 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
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 is
not GLX_TRANSPARENT_INDEX.
GLX_TRANSPARENT_RED_VALUE
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 is not
GLX_TRANSPARENT_RGB.
GLX_TRANSPARENT_GREEN_VALUE
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 is not
GLX_TRANSPARENT_RGB.
GLX_TRANSPARENT_BLUE_VALUE
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 is not
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glXGetFBConfigAttrib(3G) OpenGL Reference - GLX glXGetFBConfigAttrib(3G)
GLX_TRANSPARENT_RGB.
GLX_TRANSPARENT_ALPHA_VALUE
Integer value between 0 and the maximum frame
buffer value for alpha, indicating the transparent
blue value for the frame buffer configuration.
Undefined if GLX_TRANSPARENT_TYPE is not
GLX_TRANSPARENT_RGB.
GLX_MAX_PBUFFER_WIDTH The maximum width that can be specified to
glXCreateGLXPbuffer.
GLX_MAX_PBUFFER_HEIGHT
The maximum height that can be specified to
glXCreateGLXPbuffer.
GLX_MAX_PBUFFER_PIXELS
The maximum number of pixels (width times height)
for a pixel buffer. Note that this value may be
less than GLX_MAX_PBUFFER_WIDTH times
GLX_MAX_PBUFFER_HEIGHT. Also, this value is static
and assumes that no other pixel buffers or X
resources are contending for the frame buffer
memory. As a result, it may not be possible to
allocate a pixel buffer of the size given by
GLX_MAX_PBUFFER_PIXELS.
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.
NOTES
glXGetFBConfigAttrib is available only if the GLX version is 1.3 or
greater.
If the GLX version is 1.1 or 1.0, the GL version must be 1.0. If the GLX
version is 1.2, then the GL version must be 1.1. If the GLX version is
1.3, then the GL version must be 1.2.
ERRORS
GLX_NO_EXTENSION is returned if dpy does not support the GLX extension.
GLX_BAD_ATTRIBUTE is returned if attribute is not a valid GLX attribute.
SEE ALSO
glXGetFBConfigs, glXChooseFBConfig, glXGetVisualFromFBConfig,
glXGetConfig
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