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CDC::ArcTo

Draws an elliptical arc.

BOOL ArcTo(
   int x1,
   int y1,
   int x2,
   int y2,
   int x3,
   int y3,
   int x4,
   int y4 
);
BOOL ArcTo(
   LPCRECT lpRect,
   POINT ptStart,
   POINT ptEnd 
);

Parameters

  • x1
    Specifies the x-coordinate of the upper-left corner of the bounding rectangle (in logical units).

  • y1
    Specifies the y-coordinate of the upper-left corner of the bounding rectangle (in logical units).

  • x2
    Specifies the x-coordinate of the lower-right corner of the bounding rectangle (in logical units).

  • y2
    Specifies the y-coordinate of the lower-right corner of the bounding rectangle (in logical units).

  • x3
    Specifies the x-coordinate of the point that defines the arc's starting point (in logical units). This point does not have to lie exactly on the arc.

  • y3
    Specifies the y-coordinate of the point that defines the arc's starting point (in logical units). This point does not have to lie exactly on the arc.

  • x4
    Specifies the x-coordinate of the point that defines the arc's endpoint (in logical units). This point does not have to lie exactly on the arc.

  • y4
    Specifies the y-coordinate of the point that defines the arc's endpoint (in logical units). This point does not have to lie exactly on the arc.

  • lpRect
    Specifies the bounding rectangle (in logical units). You can pass either a pointer to a RECT data structure or a CRect object for this parameter.

  • ptStart
    Specifies the x- and y-coordinates of the point that defines the arc's starting point (in logical units). This point does not have to lie exactly on the arc. You can pass either a POINT data structure or a CPoint object for this parameter.

  • ptEnd
    Specifies the x- and y-coordinates of the point that defines the arc's ending point (in logical units). This point does not have to lie exactly on the arc. You can pass either a POINT data structure or a CPoint object for this parameter.

Return Value

Nonzero if the function is successful; otherwise 0.

Remarks

This function is similar to CDC::Arc, except that the current position is updated. The points (x1,y1) and (x2,y2) specify the bounding rectangle. An ellipse formed by the given bounding rectangle defines the curve of the arc. The arc extends counterclockwise (the default arc direction) from the point where it intersects the radial line from the center of the bounding rectangle to (x3,y3). The arc ends where it intersects the radial line from the center of the bounding rectangle to (x4,y4). If the starting point and ending point are the same, a complete ellipse is drawn.

A line is drawn from the current position to the starting point of the arc. If no error occurs, the current position is set to the ending point of the arc. The arc is drawn using the current pen; it is not filled.

Requirements

Header: afxwin.h

See Also

Concepts

CDC Class

CDC Members

Hierarchy Chart

CDC::AngleArc

CDC::Arc

CDC::SetArcDirection

ArcTo