299         void merge( ConnectedComp* comp1, ConnectedComp* comp2,  in merge()
302             comp1->growHistory( hptr, wp, -1, false );  in merge()
305             if( comp1->size < comp2->size )  in merge()
306                 std::swap(comp1, comp2);  in merge()
310                 gray_level = comp1->gray_level;  in merge()
311                 head = comp1->head;  in merge()
312                 tail = comp1->tail;  in merge()
313                 size = comp1->size;  in merge()
314                 history = comp1->history;  in merge()
318             CompHistory* h1 = comp1->history;  in merge()
321             gray_level = std::max(comp1->gray_level, comp2->gray_level);  in merge()
322             history = comp1->history;  in merge()
323             wp.pix0[comp1->tail].setNext(comp2->head);  in merge()
325             head = comp1->head;  in merge()
327             size = comp1->size + comp2->size;  in merge()