Windows begins any paint operation by aligning the brush origin with the upper-left corner of the applications client area. In the default case the upper-left corner of the brush (0,0) is mapped to the upper-left corner of the window (0,0). However, there are some instances when the default brush origin should not be used. For example, an application may use the same brush to paint the background of its parent and child windows and it may require that the child windows' background blend with the parent window background. In order to do this, the application should reset the brush origin by calling the SetBrushOrg function and shifting the origin by the required number of pixels. (An application can retrieve the current brush origin by calling the GetBrushOrgEx function.)