Include:
Prototype: short far _ellipse(short control, short x1, short y1,
short x2, short y2);
short far _ellipse_w(short control, double wx1, double wy1,
double wx2, double wy2);
short far _ellipse_wxy(short control, struct _wxycoord pwxy1,
struct _wxycoord pwxy2);
control: _GFILLINTERIOR _GBORDER
Returns: a nonzero value if the ellipse is drawn successfully; 0 if not.
See also: _arc, _floodfill, _lineto, _pie, _rectangle, _setcolor,
_setfillmask
The _ellipse functions draw an ellipse. The border is drawn in the current
color. In the ellipse function, the center of the ellipse is the center of
the bounding rectangle defined by the view coordinate points (x1, y1) and
(x2, y2).
In the _ellipse_w function, the center of the ellipse is the center of the
bounding rectangle defined by the window coordinate points (wx1, wy1) and
(wx2, wy2).
In the _ellipse_wxy function, the center of the ellipse is the center of
the bounding rectangle defined by the window coordinate pairs (pwxy1,
pwxy2).
The _ellipse_w and _ellipse_wxy routines are implemented as macros.
If the bounding-rectangle arguments define a point or a vertical or
horizontal line, no figure is drawn.
The control argument can be one of the following manifest constants:
_GFILLINTERIOR or _GBORDER.
The control option given by _GFILLINTERIOR is equivalent to a subsequent
call to the _floodfill function using the center of the ellipse as the
starting point and the current color (set by _setcolor) as the boundary
color.
Return Value
The _ellipse functions return a nonzero value if the ellipse is drawn
successfully; otherwise, they return 0.