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NAME

       XDrawLine, XDrawLines, XDrawSegments, XSegment - draw lines, polygons, and line structure

SYNTAX

       int XDrawLine(Display *display, Drawable d, GC gc, int x1, int y1, int x2, int y2);

       int  XDrawLines(Display  *display,  Drawable  d,  GC  gc, XPoint *points, int npoints, int
              mode);

       int XDrawSegments(Display *display, Drawable d, GC gc, XSegment *segments, int nsegments);

ARGUMENTS

       d         Specifies the drawable.

       display   Specifies the connection to the X server.

       gc        Specifies the GC.

       mode      Specifies   the   coordinate   mode.    You   can   pass   CoordModeOrigin    or
                 CoordModePrevious.

       npoints   Specifies the number of points in the array.

       nsegments Specifies the number of segments in the array.

       points    Specifies an array of points.

       segments  Specifies an array of segments.

       x1
       y1
       x2
       y2        Specify the points (x1, y1) and (x2, y2) to be connected.

DESCRIPTION

       The  XDrawLine function uses the components of the specified GC to draw a line between the
       specified set of points (x1, y1) and (x2, y2).  It does not perform joining at  coincident
       endpoints.   For any given line, XDrawLine does not draw a pixel more than once.  If lines
       intersect, the intersecting pixels are drawn multiple times.

       The XDrawLines function uses the components of the specified GC to  draw  npoints-1  lines
       between  each pair of points (point[i], point[i+1]) in the array of XPoint structures.  It
       draws the lines in the order listed in  the  array.   The  lines  join  correctly  at  all
       intermediate  points,  and if the first and last points coincide, the first and last lines
       also join correctly.  For any given line, XDrawLines does not draw a pixel more than once.
       If  thin  (zero  line-width)  lines  intersect, the intersecting pixels are drawn multiple
       times.  If wide lines intersect, the intersecting pixels are drawn only  once,  as  though
       the  entire PolyLine protocol request were a single, filled shape.  CoordModeOrigin treats
       all coordinates as relative to the origin, and CoordModePrevious  treats  all  coordinates
       after the first as relative to the previous point.

       The   XDrawSegments  function  draws  multiple,  unconnected  lines.   For  each  segment,
       XDrawSegments draws a line between (x1, y1) and (x2, y2).  It draws the lines in the order
       listed  in  the  array  of  XSegment structures and does not perform joining at coincident
       endpoints.  For any given line, XDrawSegments does not draw a pixel more  than  once.   If
       lines intersect, the intersecting pixels are drawn multiple times.

       All three functions use these GC components: function, plane-mask, line-width, line-style,
       cap-style, fill-style, subwindow-mode, clip-x-origin, clip-y-origin, and  clip-mask.   The
       XDrawLines  function  also uses the join-style GC component.  All three functions also use
       these GC mode-dependent components: foreground, background, tile, stipple, tile-stipple-x-
       origin, tile-stipple-y-origin, dash-offset, and dash-list.

       XDrawLine,  XDrawLines,  and  XDrawSegments  can generate BadDrawable, BadGC, and BadMatch
       errors.  XDrawLines can also generate a BadValue error.

STRUCTURES

       The XSegment structure contains:

       typedef struct {
               short x1, y1, x2, y2;
       } XSegment;

       All x and y members are signed integers.  The width and height members are 16-bit unsigned
       integers.   You  should be careful not to generate coordinates and sizes out of the 16-bit
       ranges, because the protocol only has 16-bit fields for these values.

DIAGNOSTICS

       BadDrawable
                 A value for a Drawable argument does not name a defined Window or Pixmap.

       BadGC     A value for a GContext argument does not name a defined GContext.

       BadMatch  An InputOnly window is used as a Drawable.

       BadMatch  Some argument or pair of arguments has the correct type and range but  fails  to
                 match in some other way required by the request.

       BadValue  Some  numeric  value  falls outside the range of values accepted by the request.
                 Unless a specific range is specified for an argument, the full range defined  by
                 the  argument's type is accepted.  Any argument defined as a set of alternatives
                 can generate this error.

SEE ALSO

       XDrawArc(3), XDrawPoint(3), XDrawRectangle(3)
       Xlib - C Language X Interface