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XDrawLine(3)			XLIB FUNCTIONS			  XDrawLine(3)

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 *seg-
	      ments, 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 inter-
       secting 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 in-
       tersect,	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 Win-
		 dow or	Pixmap.

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

       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

X Version 11			 libX11	1.6.5			  XDrawLine(3)

NAME | SYNTAX | ARGUMENTS | DESCRIPTION | STRUCTURES | DIAGNOSTICS | SEE ALSO

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