how to change ORTHOGRAPHIC mode to PERSPECTIVE mode

Hello,everyone.Now I want to change orthographic mode to perspective mode on view.I try many method but all failed.Could you tell me?Thank you any way.

Venugopal Gudimetla's picture

Hi,
Did you get a way to do this? if yes could you please share how you did it?
I know it has been some months may be you found an answer.
looking at :

http://www.opencascade.org/org/forum/thread_17938/