Merge pull request #8415 from Citadel-Station-13/sprint_stamina

Adds a sprint buffer - 35 tiles, regen 2 tiles/second (always active), 0.3 stamcost per tile if empty (as old) directly applied to staminaloss rather than stamina action buffer (unlike old)

modular_citadel/code/modules/mob/living/carbon/damage_procs.dm

@@ -18,3 +18,21 @@
 	if(recoveringstam && amount > 20)
 		incomingstammult = max(0.01, incomingstammult/(amount*0.05))
 	return amount
+
+/mob/living/carbon/doSprintLossTiles(tiles)
+	doSprintBufferRegen(FALSE)		//first regen.
+	if(sprint_buffer)
+		var/use = min(tiles, sprint_buffer)
+		sprint_buffer -= use
+		tiles -= use
+	update_hud_sprint_bar()
+	if(!tiles)		//we had enough, we're done!
+		return
+	adjustStaminaLoss(tiles * sprint_stamina_cost)		//use stamina to cover deficit.
+
+/mob/living/carbon/proc/doSprintBufferRegen(updating = TRUE)
+	var/diff = world.time - sprint_buffer_regen_last
+	sprint_buffer_regen_last = world.time
+	sprint_buffer = min(sprint_buffer_max, sprint_buffer + sprint_buffer_regen_ds * diff)
+	if(updating)
+		update_hud_sprint_bar()

modular_citadel/code/modules/mob/living/carbon/human/human_movement.dm

@@ -5,7 +5,7 @@
 	var/oldpseudoheight = pseudo_z_axis
 	. = ..()
 	if(. && sprinting && !(movement_type & FLYING) && canmove && !resting && m_intent == MOVE_INTENT_RUN && has_gravity(loc) && !pulledby)
-		adjustStaminaLossBuffered(0.3)
+		doSprintLossTiles(1)
 		if((oldpseudoheight - pseudo_z_axis) >= 8)
 			to_chat(src, "<span class='warning'>You trip off of the elevated surface!</span>")
 			for(var/obj/item/I in held_items)

modular_citadel/code/modules/mob/living/carbon/life.dm

@@ -0,0 +1,3 @@
+/mob/living/carbon/Life()
+	. = ..()
+	doSprintBufferRegen()

modular_citadel/code/modules/mob/living/damage_procs.dm

@@ -1,2 +1,5 @@
 /mob/living/proc/adjustStaminaLossBuffered(amount, updating_stamina = TRUE, forced = FALSE)
 	return
+
+/mob/living/proc/doSprintLossTiles(amount)
+	return

modular_citadel/code/modules/mob/living/living.dm

@@ -8,6 +8,14 @@
 	var/intentionalresting = FALSE
 	var/attemptingcrawl = FALSE
 
+	//Sprint buffer---
+	var/sprint_buffer = 42					//Tiles
+	var/sprint_buffer_max = 42
+	var/sprint_buffer_regen_ds = 0.3		//Tiles per world.time decisecond
+	var/sprint_buffer_regen_last = 0		//last world.time this was regen'd for math.
+	var/sprint_stamina_cost = 0.55			//stamina loss per tile while insufficient sprint buffer.
+	//---End
+
 /mob/living/movement_delay(ignorewalk = 0)
 	. = ..()
 	if(resting)
@@ -118,3 +126,7 @@
 		filters -= CIT_FILTER_STAMINACRIT
 		update_canmove()
 	update_health_hud()
+
+/mob/living/proc/update_hud_sprint_bar()
+	if(hud_used && hud_used.sprint_buffer)
+		hud_used.sprint_buffer.update_to_mob(src)