BOOL CreateRoundRectRgn( int x1, int y1, int x2, int y2, int x3, int y3 );
x1
Specifies the x-coordinate of the upper-left corner of the region.
y1
Specifies the y-coordinate of the upper-left corner of the region.
x2
Specifies the x-coordinate of the lower-right corner of the region.
y2
Specifies the y-coordinate of the lower-right corner of the region.
x3
Specifies the width of the ellipse used to create the rounded corners.
y3
Specifies the height of the ellipse used to create the rounded corners.
Creates a rectangular region with rounded corners that is stored in the CRgn object.
TRUE if the operation succeeded; otherwise FALSE.
CRgn::CreateRectRgn, CRgn::CreateRectRgnIndirect, ::CreateRoundRectRgn