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XDrawPoint(3)


NAME

   XDrawPoint, XDrawPoints, XPoint - draw points and points structure

SYNTAX

   int XDrawPoint(Display *display, Drawable d, GC gc, int x, int y);

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

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.

   points    Specifies an array of points.

   x
   y         Specify the x and y coordinates where you want the point
             drawn.

DESCRIPTION

   The XDrawPoint function uses the foreground pixel and function
   components of the GC to draw a single point into the specified
   drawable; XDrawPoints draws multiple points this way.  CoordModeOrigin
   treats all coordinates as relative to the origin, and CoordModePrevious
   treats all coordinates after the first as relative to the previous
   point.  XDrawPoints draws the points in the order listed in the array.

   Both functions use these GC components: function, plane-mask,
   foreground, subwindow-mode, clip-x-origin, clip-y-origin, and clip-
   mask.

   XDrawPoint can generate BadDrawable, BadGC, and BadMatch errors.
   XDrawPoints can generate BadDrawable, BadGC, BadMatch, and BadValue
   errors.

STRUCTURES

   The XPoint structure contains:

   typedef struct {
           short x, y;
   } XPoint;

   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), XDrawLine(3), XDrawRectangle(3)
   Xlib - C Language X Interface



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