question: public static void scaleRectAboutCenter ( Rect r , float scale ) { if ( scale != 1.0f ) { int cx = r . centerX ( ) ; int cy = r . centerY ( ) ; r . offset ( - cx , - cy ) ; r . left = ( int ) ( r . left * scale + 0.5f ) ; r . top = ( int ) ( r . top * scale + 0.5f ) ; r . right = ( int ) ( r . right * scale + 0.5f ) ; r . bottom = ( int ) ( r . bottom * scale + 0.5f ) ; r . offset ( cx , cy ) ; } }
target:  Scales a rect about its centroid 