part_emitter_destroy_all( ps );
This function will remove all defined emitters from the given
system and clear them from memory (this will also stop any
particles from being produced by the given emitter, but it does
NOT remove them from the room). This function should always
be called when the emitters are no longer needed for the system to
prevent memory leaks and errors.
if lives = 0
The above code checks the built in global variable "lives" and if it is 0, it destroys all particle emitters and then changes room.