experiment: explosions subsystem (#6372) [testmerge][95ba937]

code/__DEFINES/subsystems.dm

@@ -102,6 +102,7 @@
 #define INIT_ORDER_NIGHTSHIFT -24
 #define INIT_ORDER_GAME_EVENTS -26
 #define INIT_ORDER_PATH -50
+#define INIT_ORDER_EXPLOSIONS -69
 #define INIT_ORDER_PERSISTENCE -95
 #define INIT_ORDER_STATPANELS -98
 #define INIT_ORDER_DEMO	-99 // To avoid a bunch of changes related to initialization being written, do this last
@@ -139,6 +140,7 @@
 #define FIRE_PRIORITY_CHAT 			400
 #define FIRE_PRIORITY_RUNECHAT		410 // I hate how high the fire priority on this is -aa
 #define FIRE_PRIORITY_OVERLAYS		500
+#define FIRE_PRIORITY_EXPLOSIONS	666
 #define FIRE_PRIORITY_TIMER			700
 #define FIRE_PRIORITY_SPEECH_CONTROLLER 900
 #define FIRE_PRIORITY_DELAYED_VERBS 950

code/__HELPERS/data_struct/priority_queue.dm

@@ -0,0 +1,69 @@
+/priority_queue
+	var/list/priority_node/heap = list()
+
+/priority_node
+	var/item
+	var/priority
+
+/priority_node/New(item, priority)
+	. = ..()
+	src.item = item
+	src.priority = priority
+
+/priority_queue/proc/enqueue(value, priority)
+	heap += list(new /priority_node(value, priority))
+	bubble_up(heap.len)
+
+/priority_queue/proc/dequeue()
+	if (heap.len == 0)
+		return null
+
+	var/priority_node/top = heap[1]
+	var/bottom = heap[heap.len]
+	var/item = top.item
+	heap -= bottom
+	if(!heap.len)
+		qdel(top)
+		return item
+	heap[1] = bottom
+	bubble_down(1)
+	qdel(top)
+	return item
+
+/priority_queue/proc/peek()
+	if (heap.len == 0)
+		return null
+	return heap[1].item
+
+/priority_queue/proc/is_empty()
+	return heap.len == 0
+
+/priority_queue/proc/bubble_up(index)
+	while(index > 1)
+		var/parent = round(index / 2)
+
+		if (heap[parent].priority < heap[index].priority)
+			break
+
+		swap(index, parent)
+		index = parent
+
+
+/priority_queue/proc/bubble_down(index)
+	while(index * 2 <= heap.len)
+		var/child = index * 2
+
+		if (child + 1 <= heap.len && heap[child + 1].priority < heap[child].priority)
+			child++
+
+		if (heap[index].priority < heap[child].priority)
+			break
+
+		swap(index, child)
+		index = child
+
+
+/priority_queue/proc/swap(a, b)
+    var/list/temp = heap[a]
+    heap[a] = heap[b]
+    heap[b] = temp

code/__HELPERS/data_struct/queue.dm

@@ -0,0 +1,72 @@
+/*
+* Double linked list node
+*/
+/node
+	var/value
+	var/prev
+	var/next
+
+/*
+* Defining a queue based on a double linked list
+*/
+/queue
+	/// Link to the beginning of the list
+	var/node/head
+	/// Link to end of list
+	var/node/tail
+	/// Number of elements in queue
+	var/count = 0
+
+/*
+* Adding an element to the end of the queue
+*/
+/queue/proc/enqueue(value)
+	var/node/new_node = new
+	new_node.value = value
+
+	if (!tail)
+		head = new_node
+		tail = new_node
+	else
+		tail.next = new_node
+		new_node.prev = tail
+		tail = new_node
+	count++
+/*
+ * Retrieving an element from the head of the queue
+ */
+/queue/proc/dequeue()
+	if (!head)
+		return null
+
+	var/value = head.value
+	var/node/old_head = head
+
+	head = head.next
+	if (head)
+		head.prev = null
+	else
+		tail = null
+	old_head.value = null
+	qdel(old_head)
+	count--
+	return value
+/*
+* Returns an element from the beginning of the queue without removing it
+*/
+/queue/proc/peek()
+	if (!head)
+		return null
+	return head.value
+
+/*
+* Checking if the queue is empty
+*/
+/queue/proc/is_empty()
+	return count == 0
+
+/*
+* Returns the number of elements in the queue
+*/
+/queue/proc/size()
+	return count