// camera trigger setup
function triggerEvent() {
	switch(event_type) {
		case EVENT_PUSH:
			set(my, FLAG1);
			return;
	}
}

action eventTrigger() {
	c_setminmax(my);
	// sensible for push collision
	set(my, INVISIBLE | POLYGON);
	
	// make sure it always has a lower push value then the player
	my.push = player.push - 1;
	
	// make it enable push collision
	my.emask |= ENABLE_PUSH;
	my.event = triggerEvent;
	
	while(me) {
		if(is(my, FLAG1)) {
			reset(my, FLAG1);
			// call your own custom function in here!
		}
		
		wait(1);
	}
}