Ports crawling from polaris (#4118)

What the title says; you can now crawl by dragging your sprite to a title next to your character. Also allows you to buckle yourself if you are lying down.

code/game/objects/buckling.dm

@@ -56,7 +56,7 @@
 /obj/proc/user_buckle_mob(mob/living/M, mob/user)
 	if(!ROUND_IS_STARTED)
 		user << "<span class='warning'>You can't buckle anyone in before the game starts.</span>"
-	if(!user.Adjacent(M) || user.restrained() || user.lying || user.stat || istype(user, /mob/living/silicon/pai))
+	if(!user.Adjacent(M) || user.restrained() || user.stat || istype(user, /mob/living/silicon/pai))
 		return
 	if(M == buckled_mob)
 		return

code/game/turfs/turf.dm

@@ -389,3 +389,32 @@ var/const/enterloopsanity = 100
 		if(add)
 			L.Add(t)
 	return L
+
+
+/turf/MouseDrop_T(atom/movable/O as mob|obj, mob/user as mob)
+	var/turf/T = get_turf(user)
+	var/area/A = T.loc
+	if((istype(A) && !(A.has_gravity)) || (istype(T,/turf/space)))
+		return
+	if(istype(O, /obj/screen))
+		return
+	if(user.restrained() || user.stat || user.stunned || user.paralysis || !user.lying)
+		return
+	if((!(istype(O, /atom/movable)) || O.anchored || !Adjacent(user) || !Adjacent(O) || !user.Adjacent(O)))
+		return
+	if(!isturf(O.loc) || !isturf(user.loc))
+		return
+	if(isanimal(user) && O != user)
+		return
+	if(ishuman(user))
+		var/mob/living/carbon/human/H = user
+		var/has_right_hand = TRUE
+		var/obj/item/organ/external/rhand = H.organs_by_name["r_hand"]
+		if(!rhand || rhand.is_stump())
+			has_right_hand = FALSE
+		var/obj/item/organ/external/lhand = H.organs_by_name["l_hand"]
+		if(!lhand || lhand.is_stump())
+			if(!has_right_hand)
+				return
+	if (do_after(user, 25 + (5 * user.weakened)) && !(user.stat))
+		step_towards(O, src)

html/changelogs/alberyk-crawl.yml

@@ -0,0 +1,4 @@
+author: Alberyk
+delete-after: True
+changes: 
+  - rscadd: "Ported crawling mechanics from polaris: you can now crawl, if lying down, by dragging your sprite to a title near yourself."