Index for Section 3X11

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XDrawLine(3X11)
X11R6
NAME
  XDrawLine, XDrawLines, XDrawSegments, XSegment - draw lines, polygons, and
  line structure

SYNOPSIS
  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.

  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(3X11), XDrawPoint(3X11), XDrawRectangle(3X11)

  Xlib -- C Language X Interface

Index for Section 3X11

Alphabetical listing for X

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