ͬʱлӳʵ

ڻͼУҪƵõӳͼʱҪͬʱлӳʵ壬ʱFդѡʽFence״̬ʾ<Select object to trim>/<Select object to extend>/ʱ롰Fسָդߵʼ㡢мֹ㣬سȷդཻʵ嶼лӳ

ѵĶλ

ڻͼҪλһʱʹTracingܡҪһεĻһԲԲķλھεģȴԶ׽ܣcircleʱʾԲλãʱסshiftҼӵĿݲ˵ѡTrackingȻƵεױе㸽ִеοʱõ㣬ٽϷƵεұе㸽ִͬеοʱ꣬سͽԲĶλ˾εģӦİ뾶ɡ