Is there any way that we can use to check whether the entity or particle is inside the view or out?
What I want to do is to remove the bullets and their particles once they leave the viewing screen to improve performance...

Thanks

You can use the CLIPPED flag or check_view().
When using the latter you could also have a look at this thread: http://www.opserver.de/ubb7/ubbthreads.php?ubb=showflat&Number=350775#Post350775