HP b2600 Reference Manual page 189

G
glXGetConfig
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 GLX_RGBA is False.
GLX_GREEN_SIZE
Number of bits of green stored in each color buffer. Undefined if GLX_RGBA is False.
GLX_BLUE_SIZE
Number of bits of blue stored in each color buffer. Undefined if GLX_RGBA is False.
GLX_ALPHA_SIZE
Number of bits of alpha stored in each color buffer. Undefined if GLX_RGBA is False.
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.
The X protocol allows a single visual ID to be instantiated with different numbers of bits
per pixel. Windows or GLX pixmaps that will be rendered with OpenGL, however, must
be instantiated with a color buffer depth of GLX_BUFFER_SIZE.
Although a GLX implementation can export many visuals that support GL rendering, it
must support at least one RGBA visual. This visual 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 visual. However, its color buffer size must be
as great as that of the deepest TrueColor, DirectColor, PseudoColor, or StaticColor visual
supported on level zero, and it must itself be made available on level zero.
In addition, if the X server exports a PseudoColor or StaticColor visual on frame buffer
level 0, a color index visual is also required on that level. It must have at least one color
buffer, a stencil buffer of at least 1 bit, and depth buffer of at least 12 bits. This visual
must have as many color bitplanes as the deepest PseudoColor or StaticColor visual
supported on level 0.
Applications are best written to select the visual that most closely meets their
requirements. Creating windows or GLX pixmaps with unnecessary buffers can result in
reduced rendering performance as well as poor resource allocation.
189
Chapter 7