XDrawLine(3X11)     X Version 11 (Release 4)      XDrawLine(3X11)



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

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

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

       XDrawSegments(display, d, gc, segments, nsegments)
             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.



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       points    Specifies a pointer to an array of points.

       segments  Specifies a pointer to 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


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       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.




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       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(3X11), XDrawPoint(3X11), XDrawRectangle(3X11)
       Xlib - C Language X Interface




























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