用mfc画圆时 pDC->Ellipse（0,25,37,46） 里面的参数各代表什么意思啊

左上角和右下角的坐标CDC::Ellipse BOOL Ellipse( int x1,int y1,int x2,int y2 );BOOL Ellipse( LPCRECT lpRect );Return ValueNonzero if the function is successful; otherwise 0。Parametersx1Specifies the logical x-coordinate of the upper-left corner of the ellipse’s bounding rectangle。y1Specifies the logical y-coordinate of the upper-left corner of the ellipse’s bounding rectangle。x2Specifies the logical x-coordinate of the lower-right corner of the ellipse’s bounding rectangle。y2Specifies the logical y-coordinate of the lower-right corner of the ellipse’s bounding rectangle。lpRectSpecifies the ellipse’s bounding rectangle。You can also pass a CRect object for this paramete