+ Rect r ;
+ GetPortBounds( GetWindowPort( m_window ) , &r ) ;
+ if ( m_rect.top < 0 )
+ {
+ m_rect.bottom += -m_rect.top ;
+ m_rect.top = 0 ;
+ }
+ if ( m_rect.left < 0 )
+ {
+ m_rect.right += -m_rect.left ;
+ m_rect.left = 0 ;
+ }
+ if ( m_rect.right > r.right )
+ {
+ m_rect.left -= (m_rect.right - r.right ) ;
+ m_rect.right = r.right ;
+ }
+ if ( m_rect.bottom > r.bottom )
+ {
+ m_rect.top -= (m_rect.bottom - r.bottom) ;
+ m_rect.bottom = r.bottom ;
+ }