[vtkusers] How to pick very small actors?

[cokio]

Hi, all:         
	   
       I find that some actor is really small that i can't pick it by myself , so I look for some new pick method.
 I see actor-Pick() in the list of actor's member functions. I hope actor->Pick() can pick the actor I need, but it
 seems that the actor is not picked. I can locate the actor, set its color, change its position, etc. But if I want
 to PICK AN ACTOR , do I HAVE TO use  MOUSE to LOCATE IT and use a userdefined KEY ON THE KEYBOARD (default is p) to 
 PICK IT? 
       When some actors are close to each other, it seems very difficult to pick the actor u want, especially the very 
small one. So I hope someone can give me some advice.
       Thank u!
　　　　　　　　
 				

　　　　　　　　cokio
　　　　　　　　cokio at sjtu.edu.cn