NAME

       xgc - X graphics demo

SYNOPSIS

       xgc [-toolkitoption ...]

DESCRIPTION

       The  xgc  program  demonstrates various features of the X graphics primitives.  In X, most of the details
       about the graphics to be generated are stored in a resource called a  graphics  context  (GC).   The  xgc
       program  provides  a  user interface for setting various GC components.  Pressing the "Run" button causes
       these results to be displayed in the large drawing window on the right.  Timing information is  displayed
       in the window immediately below.

       The items in the upper left hand window work as follows:

       Function  -  specify  the  logical  function with which primitives will drawn.  The most usual setting is
       "set", i.e. simply to render pixels without regard to what has been drawn before.

       LineStyle - specify whether  lines  should  be  drawn  solid  in  foreground,  dashed  in  foreground  or
       alternating foreground and background.

       CapStyle - specify the appearance of the ends of a line.

       JoinStyle  -  specify  the  appearance of joints between consecutive lines drawn within a single graphics
       primitive.

       FillStyle - specify whether lines, text and fill requests are solid, tiled with a pixmap or stippled.

       FillRule - specifies the rule used to fill polygons.  The EvenOdd rule means that if areas overlap an odd
       number  of  times,  they  are  not  drawn.   Winding rule means that overlapping areas are always filled,
       regardless of how many times they overlap.

       ArcMode - specifies the rule for filling of arcs.  The boundary of the arc  is  either  a  Chord  or  two
       radii.

       planemask  -  specifies  which  planes  of  the  drawing window are modified.  By default, all planes are
       modified.

       dashlist - specifies a pattern to be used when drawing dashed lines.

       Line Width - specifies the width in pixels of lines to be drawn.  Zero means to draw using  the  server's
       fastest algorithm with a line width of one pixel.

       Font - specifies the font to be used for text primitives.

       Foreground  and  Background  -  specify  the  pixel  values  to  be applied when drawing primitives.  The
       Foreground value is used as the pixel value for set bits in the source in all primitives.  The Background
       value  is  used as the pixel value for unset bits in the source when using Copy Plane, drawing lines with
       LineStyle of DoubleDash and filling with FillStyle of OpaqueStippled.

       Percentage of Test - scrollbar permits specifying only a percentage of the test to be run.  The number at
       the left indicates the current setting, which defaults to 100%.

       The  window  labeled "Test" permits choice of one a number of graphics primitive tests, including Points,
       Segments, Lines, Arcs and Filled Arcs, 8-bit Text and Image Text, Rectangles and Filled Rectangles, Image
       draws, as well as Copy Plane and Copy Area.

       The window to the right of this has buttons which permit record/playback of the primitives rendered.

OPTIONS

       Xgc accepts all of the standard X Toolkit command line options.

X DEFAULTS

       This program accepts the usual defaults for toolkit applications.

ENVIRONMENT

       DISPLAY to get the default host and display number.

       XENVIRONMENT
               to  get  the  name  of  a  resource  file  that  overrides  the  global  resources  stored in the
               RESOURCE_MANAGER property.

SEE ALSO

       X(7)

BUGS

       This program isn't really finished yet, but it probably never will be, since  it  only  demonstrates  the
       original X11 core protocol rendering operations, which few modern programs use anymore.

AUTHORS

       Dan Schmidt, MIT