reverts forensics components. If I can't figure it out, MURDER IT

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

@@ -82,7 +82,8 @@
 				add_blood = bloodiness
 			bloodiness -= add_blood
 			S.blood_smear[blood_state] = min(MAX_SHOE_BLOODINESS,S.blood_smear[blood_state]+add_blood)
-			S.add_blood_DNA(return_blood_DNA())
+			if(blood_DNA && blood_DNA.len)
+				S.add_blood(blood_DNA)
 			S.blood_state = blood_state
 			S.blood_color = blood_color
 			update_icon()
@@ -97,7 +98,8 @@
 			bloodiness -= add_blood
 			H.blood_smear[blood_state] = min(MAX_SHOE_BLOODINESS,H.blood_smear[blood_state]+add_blood)
 			H.bloodiness = add_blood
-			H.add_blood_DNA(return_blood_DNA())
+			if(blood_DNA && blood_DNA.len)
+				H.add_blood(blood_DNA)
 			H.blood_state = blood_state
 			H.blood_color = blood_color
 			update_icon()

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

@@ -4,10 +4,7 @@
 	name = "xeno blood"
 	desc = "It's green and acidic. It looks like... <i>blood?</i>"
 	color = BLOOD_COLOR_XENO
-
-/obj/effect/decal/cleanable/blood/xeno/Initialize()
-	. = ..()
-	add_blood_DNA(list("UNKNOWN DNA" = "X*"))
+	blood_DNA = list("UNKNOWN DNA" = "X*")
 
 /obj/effect/decal/cleanable/blood/splatter/xeno
 	color = BLOOD_COLOR_XENO
@@ -64,6 +61,10 @@
 /obj/effect/decal/cleanable/blood/gibs/xeno/larva/body
 	random_icon_states = list("xgiblarvahead", "xgiblarvatorso")
 
-/obj/effect/decal/cleanable/blood/xeno/tracks/Initialize()
-	. = ..()
-	add_blood_DNA(list("UNKNOWN DNA" = "X*"))
+/obj/effect/decal/cleanable/blood/xtracks
+	icon_state = "tracks"
+	random_icon_states = null
+
+/obj/effect/decal/cleanable/blood/xtracks/Initialize()
+	add_blood(list("UNKNOWN DNA" = "X*"))
+	. = ..()

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

@@ -48,6 +48,7 @@
 				diseases = infective.diseases
 			var/obj/effect/decal/cleanable/blood/gibs/gibbers = src
 			var/obj/effect/decal/cleanable/blood/splatter/splat = new /obj/effect/decal/cleanable/blood/splatter(loc, diseases)
+			splat.transfer_blood_dna(blood_DNA)
 			splat.color = gibbers.blood_color
 			splat.blood_color = gibbers.blood_color
 
@@ -87,7 +88,7 @@
 	. = ..()
 	setDir(pick(1,2,4,8))
 	icon_state += "-old"
-	add_blood_DNA(list("Non-human DNA" = "A+"))
+	add_blood(list("Non-human DNA" = "A+"))
 
 /obj/effect/decal/cleanable/blood/drip
 	name = "drips of blood"

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

@@ -4,40 +4,28 @@
 	icon = 'icons/effects/blood.dmi'
 	icon_state = "floor1"
 	random_icon_states = list("floor1", "floor2", "floor3", "floor4", "floor5", "floor6", "floor7")
+	blood_DNA = list()
 	blood_state = BLOOD_STATE_BLOOD
 	color = BLOOD_COLOR_HUMAN //default so we don't have white splotches everywhere.
 	bloodiness = BLOOD_AMOUNT_PER_DECAL
 
 
 /obj/effect/decal/cleanable/blood/replace_decal(obj/effect/decal/cleanable/blood/C)
-	if(bloodiness)
-		if(C.bloodiness < MAX_SHOE_BLOODINESS)
-			C.bloodiness += bloodiness
+	if (C.blood_DNA)
+		blood_DNA |= C.blood_DNA.Copy()
 	update_icon()
-	return ..()
+	..()
 
-/obj/effect/decal/cleanable/blood/add_blood_DNA(list/blood_dna)
-	return TRUE
+/obj/effect/decal/cleanable/blood/transfer_blood_dna()
+	..()
+	update_icon()
 
 /obj/effect/decal/cleanable/blood/transfer_mob_blood_dna()
 	. = ..()
 	update_icon()
 
 /obj/effect/decal/cleanable/blood/update_icon()
-	if(!blood_color)
-		if(reagents.reagent_list.len)
-			for(var/datum/reagent/R in reagents.reagent_list)
-				// Get blood data from the blood reagent.
-				if(istype(R, /datum/reagent/blood))
-					if(R.data["blood_type"])
-						blood_color = bloodtype_to_color(R.data["blood_type"])
-				else if(istype(R, /datum/reagent/liquidgibs))
-					if(R.data["blood_type"])
-						blood_color = bloodtype_to_color(R.data["blood_type"])
-		else
-			return
-	else
-		color = blood_color
+	color = blood_DNA_to_color()
 
 //obj/effect/decal/cleanable/blood/update_color()
  // if(SEND_SIGNAL(COMSIG_BLOOD_COLOR) & COMPONENT_BLOCK_UPDATE_COLOR)
@@ -50,8 +38,9 @@
 	color = "#3a0505"
 
 /obj/effect/decal/cleanable/blood/old/Initialize(mapload, list/datum/disease/diseases)
-	. = ..()
-	add_blood_DNA(list("blood_type"= "A+"))
+	..()
+	icon_state += "-old"
+	add_blood(list("Non-human DNA" = "A+"))
 
 /obj/effect/decal/cleanable/blood/splatter
 	random_icon_states = list("gibbl1", "gibbl2", "gibbl3", "gibbl4", "gibbl5")
@@ -66,10 +55,7 @@
 	bloodiness = BLOOD_AMOUNT_PER_DECAL
 
 /obj/effect/decal/cleanable/trail_holder/update_icon()
-	GET_COMPONENT(D, /datum/component/forensics)
-	if(istype(D) && !blood_color)
-		blood_color = D.blood_mix_color
-	color = blood_color
+	color = blood_DNA_to_color()
 
 /obj/effect/cleanable/trail_holder/Initialize()
 	. = ..()
@@ -78,6 +64,10 @@
 /obj/effect/decal/cleanable/trail_holder/can_bloodcrawl_in()
 	return TRUE
 
+/obj/effect/decal/cleanable/trail_holder/transfer_blood_dna()
+	..()
+	update_icon()
+
 /obj/effect/decal/cleanable/trail_holder/transfer_mob_blood_dna()
 	. = ..()
 	update_icon()
@@ -122,6 +112,8 @@
 		var/mob/living/carbon/human/H = O
 		var/obj/item/clothing/shoes/S = H.shoes
 		if(S && S.blood_smear[blood_state])
+			if(color != bloodtype_to_color(S.last_bloodtype))//last entry - we check its color
+				return
 			S.blood_smear[blood_state] = max(S.blood_smear[blood_state] - BLOOD_LOSS_PER_STEP, 0)
 			S.blood_color = blood_color
 			shoe_types  |= S.type
@@ -138,6 +130,7 @@
 				update_icon()
 
 /obj/effect/decal/cleanable/blood/footprints/tracks/update_icon()
+	..()
 	cut_overlays()
 
 	for(var/Ddir in GLOB.cardinals)

code/game/objects/effects/spawners/gibspawner.dm

@@ -12,8 +12,6 @@
 
 /obj/effect/gibspawner/Initialize(mapload, mob/living/source_mob, list/datum/disease/diseases)
 	. = ..()
-	AddComponent(/datum/component/forensics)
-
 	if(gibtypes.len != gibamounts.len)
 		stack_trace("Gib list amount length mismatch!")
 		return
@@ -74,7 +72,7 @@
 					var/mob/living/carbon/digester = loc
 					digester.stomach_contents += gib
 
-				gib.add_blood_DNA(dna_to_add)
+				gib.blood_DNA += dna_to_add
 				// color them properly, please.
 				gib.body_colors = body_coloring
 				gib.update_icon()

code/game/objects/effects/temporary_visuals/miscellaneous.dm

@@ -43,7 +43,7 @@
 	animate(src, pixel_x = target_pixel_x, pixel_y = target_pixel_y, alpha = 0, time = duration)
 
 /obj/effect/temp_visual/dir_setting/bloodsplatter/xenosplatter
-	splatter_type = "xsplatter"
+	color = BLOOD_COLOR_XENO
 
 /obj/effect/temp_visual/dir_setting/speedbike_trail
 	name = "speedbike trails"