Reduce cost of xenoarch jungle generation significantly

code/game/turfs/simulated/river.dm

@@ -73,33 +73,35 @@
 /turf/proc/Spread(probability = 30, prob_loss = 25, whitelisted_area)
 	if(probability <= 0)
 		return
-	var/list/cardinal_turfs = list()
-	var/list/diagonal_turfs = list()
 	var/logged_turf_type
 	for(var/turf/T in orange(1, src))
 		var/area/new_area = get_area(T)
-		if(!T || (T.density && !ismineralturf(T)) || istype(T, /turf/open/indestructible) || (whitelisted_area && !istype(new_area, whitelisted_area)) || (T.flags_1 & NO_LAVA_GEN_1) )
+		if((T.density && !ismineralturf(T)) || istype(T, /turf/open/indestructible) || (whitelisted_area && !istype(new_area, whitelisted_area)) || (T.flags_1 & NO_LAVA_GEN_1) )
 			continue
 
 		if(!logged_turf_type && ismineralturf(T))
 			var/turf/closed/mineral/M = T
 			logged_turf_type = M.turf_type
 
-		if(get_dir(src, T) in GLOB.cardinals)
-			cardinal_turfs += T
-		else
-			diagonal_turfs += T
-
-	for(var/turf/T as anything in cardinal_turfs) //cardinal turfs are always changed but don't always spread
-		if(!istype(T, logged_turf_type) && T.ChangeTurf(type, baseturfs, CHANGETURF_IGNORE_AIR) && prob(probability))
-			T.Spread(probability - prob_loss, prob_loss, whitelisted_area)
-
-	for(var/turf/T as anything in diagonal_turfs) //diagonal turfs only sometimes change, but will always spread if changed
-		if(!istype(T, logged_turf_type) && prob(probability) && T.ChangeTurf(type, baseturfs, CHANGETURF_IGNORE_AIR))
-			T.Spread(probability - prob_loss, prob_loss, whitelisted_area)
-		else if(ismineralturf(T))
-			var/turf/closed/mineral/M = T
-			M.ChangeTurf(M.turf_type, M.baseturfs, CHANGETURF_IGNORE_AIR)
+	for(var/turf/T in orange(1, src))
+		var/area/new_area = get_area(T)
+		if((T.density && !ismineralturf(T)) || istype(T, /turf/open/indestructible) || (whitelisted_area && !istype(new_area, whitelisted_area)) || (T.flags_1 & NO_LAVA_GEN_1) )
+			continue
+		var/opponent_dir = get_dir(src, T) // Use some clever bitmath to check if the direction is diagonal.
+		if(opponent_dir & (opponent_dir - 1)) //diagonal turfs only sometimes change, but will always spread if changed
+			// NOTE: WE ARE SKIPPING CHANGETURF HERE
+			// The calls in this proc only serve to provide a satisfactory (if it's not ALREADY this) check. They do not actually call changeturf
+			// This is safe because this proc can only be run during mapload, and nothing has initialized by now so there's nothing to inherit or delete
+			if(!istype(T, logged_turf_type) && !istype(T, type) && prob(probability) && T.ChangeTurf(type, baseturfs, CHANGETURF_SKIP))
+				T.Spread(probability - prob_loss, prob_loss, whitelisted_area)
+			else if(ismineralturf(T))
+				var/turf/closed/mineral/M = T
+				// SEE ABOVE, THIS IS ONLY VERY RARELY SAFE
+				M.ChangeTurf(M.turf_type, M.baseturfs, CHANGETURF_SKIP)
+		else //cardinal turfs are always changed but don't always spread
+			// Important NOTE: SEE ABOVE
+			if(!istype(T, logged_turf_type) && !istype(T, type) && T.ChangeTurf(type, baseturfs, CHANGETURF_SKIP) && prob(probability))
+				T.Spread(probability - prob_loss, prob_loss, whitelisted_area)
 
 
 #undef RANDOM_UPPER_X

modular_splurt/code/modules/mapping/lavaland_jungle_gen.dm

@@ -27,7 +27,7 @@
 			continue
 		W.connected = 1
 		var/turf/cur_turf = get_turf(W)
-		cur_turf.ChangeTurf(turf_type, new_baseturfs, CHANGETURF_IGNORE_AIR)
+		cur_turf.ChangeTurf(turf_type, new_baseturfs, CHANGETURF_SKIP) // HEY! Don't use CHANGETURF_SKIP unless you're SURE it can only ever run prior to turf init!
 		var/turf/target_turf = get_turf(pick(river_nodes - W))
 		if(!target_turf)
 			break
@@ -56,7 +56,7 @@
 				cur_turf = get_step(cur_turf, cur_dir)
 				continue
 			else
-				var/turf/river_turf = cur_turf.ChangeTurf(turf_type, new_baseturfs, CHANGETURF_IGNORE_AIR)
+				var/turf/river_turf = cur_turf.ChangeTurf(turf_type, new_baseturfs, CHANGETURF_SKIP) // HEY! Don't use CHANGETURF_SKIP unless you're SURE it can only ever run prior to turf init!
 				river_turf.Spread(30, 11, whitelist_area)
 
 	for(var/WP in river_nodes)
@@ -111,7 +111,7 @@
 					if(Trange <= radius + 0.5)
 						var/circ_area = get_area(T)
 						if(istype(circ_area, whitelist_area))
-							T.ChangeTurf(turf_type, new_baseturfs, CHANGETURF_IGNORE_AIR)
+							T.ChangeTurf(turf_type, new_baseturfs, CHANGETURF_SKIP) // HEY! Don't use CHANGETURF_SKIP unless you're SURE it can only ever run prior to turf init!
 							affected |= T
 							if(Trange > radius - 1)
 								T.Spread(21, 11, whitelist_area)
@@ -126,21 +126,21 @@
 						dir_turf = get_step(dir_turf, dir)
 						var/dir_area = get_area(dir_turf)
 						if(istype(dir_area, whitelist_area))
-							dir_turf = dir_turf.ChangeTurf(turf_type, new_baseturfs, CHANGETURF_IGNORE_AIR)
+							dir_turf = dir_turf.ChangeTurf(turf_type, new_baseturfs, CHANGETURF_SKIP) // HEY! Don't use CHANGETURF_SKIP unless you're SURE it can only ever run prior to turf init!
 							affected |= dir_turf
 							if(i == radius)
 								dir_turf.Spread(21, 11, whitelist_area)
 						//Fixes to diagional checker board
-						if(dir in GLOB.diagonals)
+						if(dir & (dir-1))
 							var/turf/diag_turf = locate(dir_turf.x,(dir_turf.y-1),target_z)
 							var/diag_area = get_area(diag_turf)
 							if(istype(diag_area, whitelist_area))
-								diag_turf = diag_turf.ChangeTurf(turf_type, new_baseturfs, CHANGETURF_IGNORE_AIR)
+								diag_turf = diag_turf.ChangeTurf(turf_type, new_baseturfs, CHANGETURF_SKIP) // HEY! Don't use CHANGETURF_SKIP unless you're SURE it can only ever run prior to turf init!
 								affected |= diag_turf
 
 			var/area/new_area = get_area(cur_turf)
 			if(istype(new_area, whitelist_area))
-				cur_turf.ChangeTurf(turf_type, new_baseturfs, CHANGETURF_IGNORE_AIR)
+				cur_turf.ChangeTurf(turf_type, new_baseturfs, CHANGETURF_SKIP) // HEY! Don't use CHANGETURF_SKIP unless you're SURE it can only ever run prior to turf init!
 				affected |= cur_turf
 			else
 				detouring = 0