[MIRROR] Makes bloody footprints messier (#28647)

* Makes bloody footprints messier (#84665)

## About The Pull Request

Makes bloody shoes loose less blood per step, meaning that they trail
more blood. Updates the equation for determining footprint alpha to
account for this change.
(Bloodiness of 50, 100, 150 from left to right)
Before:

![image](https://github.com/tgstation/tgstation/assets/40921881/302a9041-b127-4ede-b9cf-edfb8aa042fc)
After:

![image](https://github.com/tgstation/tgstation/assets/40921881/55ffd4b9-b9eb-4448-9998-9f4a3a04b629)

## Why It's Good For The Game

Right now footprint go like 2-3 steps before stopping, feels kinda lame.
🕵️

## Changelog

🆑 Seven
balance: Bloody footprint trails go a longer distance now.
/🆑

* Makes bloody footprints messier

---------

Co-authored-by: Lufferly <40921881+Lufferly@users.noreply.github.com>

code/datums/components/bloodysoles.dm

@@ -1,3 +1,5 @@
+/// The percentage of blood we lose on each step
+#define BLOOD_PERCENT_LOSS_ON_STEP 0.33
 
 /**
  * Component for clothing items that can pick up blood from decals and spread it around everywhere when walking, such as shoes or suits with integrated shoes.
@@ -172,10 +174,11 @@
 	if(wielder.body_position == LYING_DOWN || !wielder.has_gravity(wielder.loc))
 		return
 
-	var/half_our_blood = bloody_shoes[last_blood_state] / 2
+	var/blood_lost = bloody_shoes[last_blood_state] * BLOOD_PERCENT_LOSS_ON_STEP
+	var/theoretical_new_blood = bloody_shoes[last_blood_state] - blood_lost
 	var/footprint_sprite = wielder.get_footprint_sprite()
 	// Add footprints in old loc if we have enough cream
-	if(half_our_blood >= BLOOD_FOOTPRINTS_MIN)
+	if(theoretical_new_blood >= BLOOD_FOOTPRINTS_MIN)
 		var/turf/oldLocTurf = get_turf(OldLoc)
 		var/obj/effect/decal/cleanable/blood/footprints/oldLocFP = find_pool_by_blood_state(oldLocTurf, /obj/effect/decal/cleanable/blood/footprints, footprint_sprite)
 		if(oldLocFP)
@@ -186,7 +189,7 @@
 				oldLocFP.update_appearance()
 		else if(find_pool_by_blood_state(oldLocTurf, footprint_sprite = footprint_sprite))
 			// No footprints in the tile we left, but there was some other blood pool there. Add exit footprints on it
-			adjust_bloody_shoes(last_blood_state, half_our_blood)
+			adjust_bloody_shoes(last_blood_state, blood_lost)
 			update_icon()
 
 			oldLocFP = new(oldLocTurf, footprint_sprite)
@@ -194,19 +197,20 @@
 				oldLocFP.blood_state = last_blood_state
 				oldLocFP.exited_dirs |= wielder.dir
 				add_parent_to_footprint(oldLocFP)
-				oldLocFP.bloodiness = half_our_blood
+				oldLocFP.bloodiness = blood_lost
 				oldLocFP.add_blood_DNA(GET_ATOM_BLOOD_DNA(parent_atom))
 				oldLocFP.update_appearance()
 
-			half_our_blood = bloody_shoes[last_blood_state] / 2
+			blood_lost = bloody_shoes[last_blood_state] * BLOOD_PERCENT_LOSS_ON_STEP
+			theoretical_new_blood = theoretical_new_blood - blood_lost
 
 	// If we picked up the blood on this tick in on_step_blood, don't make footprints at the same place
 	if(last_pickup && last_pickup == world.time)
 		return
 
 	// Create new footprints
-	if(half_our_blood >= BLOOD_FOOTPRINTS_MIN)
-		adjust_bloody_shoes(last_blood_state, half_our_blood)
+	if(theoretical_new_blood >= BLOOD_FOOTPRINTS_MIN)
+		adjust_bloody_shoes(last_blood_state, blood_lost)
 		update_icon()
 
 		var/obj/effect/decal/cleanable/blood/footprints/FP = new(get_turf(parent_atom), footprint_sprite)
@@ -214,7 +218,7 @@
 			FP.blood_state = last_blood_state
 			FP.entered_dirs |= wielder.dir
 			add_parent_to_footprint(FP)
-			FP.bloodiness = half_our_blood
+			FP.bloodiness = blood_lost
 			FP.add_blood_DNA(GET_ATOM_BLOOD_DNA(parent_atom))
 			FP.update_appearance()
 
@@ -234,7 +238,7 @@
 		// The pool we stepped in was actually footprints with the same type
 		var/obj/effect/decal/cleanable/blood/footprints/pool_FP = pool
 		add_parent_to_footprint(pool_FP)
-		if((bloody_shoes[last_blood_state] / 2) >= BLOOD_FOOTPRINTS_MIN && !(pool_FP.entered_dirs & wielder.dir))
+		if((bloody_shoes[last_blood_state] - (bloody_shoes[last_blood_state] * BLOOD_PERCENT_LOSS_ON_STEP)) >= BLOOD_FOOTPRINTS_MIN && !(pool_FP.entered_dirs & wielder.dir))
 			// If our feet are bloody enough, add an entered dir
 			pool_FP.entered_dirs |= wielder.dir
 			pool_FP.update_appearance()
@@ -328,3 +332,5 @@
 	SIGNAL_HANDLER
 
 	update_icon()
+
+#undef BLOOD_PERCENT_LOSS_ON_STEP

code/game/objects/effects/decals/cleanable/humans.dm

@@ -296,7 +296,7 @@
 
 /obj/effect/decal/cleanable/blood/footprints/update_icon()
 	. = ..()
-	alpha = min(BLOODY_FOOTPRINT_BASE_ALPHA + (255 - BLOODY_FOOTPRINT_BASE_ALPHA) * bloodiness / (BLOOD_ITEM_MAX / 2), 255)
+	alpha = max(BLOODY_FOOTPRINT_BASE_ALPHA, min(255 * (bloodiness / 15), 255))
 
 //Cache of bloody footprint images
 //Key: