question: public void intersection ( Rectangle2D r ) { if ( status == INVALID ) return ; if ( status == EMPTY ) { setClip ( r ) ; status = INUSE ; return ; } clip [ 0 ] = Math . max ( clip [ 0 ] , r . getMinX ( ) ) ; clip [ 1 ] = Math . max ( clip [ 1 ] , r . getMinY ( ) ) ; clip [ 6 ] = Math . min ( clip [ 6 ] , r . getMaxX ( ) ) ; clip [ 7 ] = Math . min ( clip [ 7 ] , r . getMaxY ( ) ) ; }
target:  Intersect this clip with another region. As a result, this clip will become the intersecting area of the two regions.