ENTITY* eSlot1 =
{
	layer = 6; // display above view entities with layer 1
//the type is defined later
	flags2 = VISIBLE; // visible on screen from the start
}

...//the following is inside my main while loop:
		if(key_i == 1)
		{
			while(key_i == 1){wait(1);}
			toggle(eSlot1,VISIBLE);
...

eSlot1.flags2 ^= VISIBLE;