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GLXUSEXFONT()                                                    GLXUSEXFONT()

NAME
       glXUseXFont - create bitmap display lists from an X font

C SPECIFICATION
       void glXUseXFont( Font font,
                         int first,
                         int count,
                         int listBase )

PARAMETERS
       font      Specifies the font from which character glyphs are to be
                 taken.

       first     Specifies the index of the first glyph to be taken.

       count     Specifies the number of glyphs to be taken.

       listBase  Specifies the index of the first display list to be
                 generated.

DESCRIPTION
       glXUseXFont generates count display lists, named listBase through
       listBase+count-1, each containing a single glBitmap command.  The
       parameters of the glBitmap command of display list listBase+i are
       derived from glyph first+i.  Bitmap parameters xorig, yorig, width, and
       height are computed from font metrics as descent-1, -lbearing,
       rbearing-lbearing, and ascent+descent, respectively.  xmove is taken
       from the glyph's width metric, and ymove is set to zero.  Finally, the
       glyph's image is converted to the appropriate format for glBitmap.

       Using glXUseXFont may be more efficient than accessing the X font and
       generating the display lists explicitly, both because the display lists
       are created on the server without requiring a round trip of the glyph
       data, and because the server may choose to delay the creation of each
       bitmap until it is accessed.

       Empty display lists are created for all glyphs that are requested and
       are not defined in font.  glXUseXFont is ignored if there is no current
       GLX context.

ERRORS
       BadFont is generated if font is not a valid font.

       GLXBadContextState is generated if the current GLX context is in
       display-list construction mode.

       GLXBadCurrentWindow is generated if the drawable associated with the
       current context of the calling thread is a window, and that window is
       no longer valid.

SEE ALSO
       glBitmap, glXMakeCurrent

                                                                 GLXUSEXFONT()