CreateEllipticRgn

HRGN CreateEllipticRgn(nLeftRect, nTopRect, nRightRect, nBottomRect)
int nLeftRect;	/* x-coordinate upper-left corner bounding rectangle	*/
int nTopRect;	/* y-coordinate upper-left corner bounding rectangle	*/
int nRightRect;	/* x-coordinate lower-right corner bounding rectangle	*/
int nBottomRect;	/* y-coordinate lower-right corner bounding rectangle	*/

The CreateEllipticRgn function creates an elliptical region.

Parameters

nLeftRect

Specifies the x-coordinate of the upper-left corner of the bounding rectangle of the ellipse.

nTopRect

Specifies the y-coordinate of the upper-left corner of the bounding rectangle of the ellipse.

nRightRect

Specifies the x-coordinate of the lower-right corner of the bounding rectangle of the ellipse.

nBottomRect

Specifies the y-coordinate of the lower-right corner of the bounding rectangle of the ellipse.

Return Value

The return value is the handle of a region if the function is successful. Otherwise, it is NULL.

Comments

A bounding rectangle defines the size, shape, and orientation of the elliptic region: the longest sides of the rectangle define the length of the ellipse's major axis; the shorter sides define the length of the ellipse's minor axis; and, the center of the rectangle defines the intersection of the major and the minor axis.