add mob_area_spawn setting

api.lua

@@ -8,7 +8,7 @@ local use_cmi = minetest.global_exists("cmi")
 
 mobs = {
 	mod = "redo",
-	version = "20201115",
+	version = "20201130",
 	intllib = S,
 	invis = minetest.global_exists("invisibility") and invisibility or {}
 }
@@ -58,6 +58,7 @@ local mobs_drop_items = settings:get_bool("mobs_drop_items") ~= false
 local mobs_griefing = settings:get_bool("mobs_griefing") ~= false
 local spawn_protected = settings:get_bool("mobs_spawn_protected") ~= false
 local remove_far = settings:get_bool("remove_far_mobs") ~= false
+local mob_area_spawn = settings:get_bool("mob_area_spawn")
 local difficulty = tonumber(settings:get("mob_difficulty")) or 1.0
 local show_health = settings:get_bool("mob_show_health") ~= false
 local max_per_block = tonumber(settings:get("max_objects_per_block") or 99)
@@ -3908,8 +3909,27 @@ function mobs:spawn_specific(name, nodes, neighbors, min_light, max_light, inter
 			end
 		end
 
+		-- should we check mob area for obstructions ?
+		if mob_area_spawn ~= true then
+
+			-- do we have enough height clearance to spawn mob?
+			local ent = minetest.registered_entities[name]
+			local height = max(1, math.ceil(
+				(ent.collisionbox[5] or 0.25) - (ent.collisionbox[2] or -0.25) - 1))
+
+			for n = 0, height do
+
+				local pos2 = {x = pos.x, y = pos.y + n, z = pos.z}
+
+				if minetest.registered_nodes[node_ok(pos2).name].walkable == true then
+--print ("--- inside block", name, node_ok(pos2).name)
+					return
+				end
+			end
+		else
 			-- returns position if we have enough space to spawn mob
 			pos = can_spawn(pos, name)
+		end
 
 		if pos then
 

api.txt

@@ -697,6 +697,9 @@ External Settings for "minetest.conf"
                             function.
    'mob_nospawn_range'      Minimum range a mob can spawn near player (def: 12)
    'mob_active_limit'       Number of active mobs in game, 0 for unlimited
+   'mob_area_spawn'         When true will check surrounding area the size of the
+                            mob for obstructions before spawning, otherwise it
+                            defaults to checking the height of the mob only.
 
 Players can override the spawn chance for each mob registered by adding a line
 to their minetest.conf file with a new value, the lower the value the more each

settingtypes.txt

@@ -33,3 +33,6 @@ mob_nospawn_range (Mob no-spawn range) float 12.0
 
 #    Sets maximum number of active mobs in game (0 for unlimited)
 mob_active_limit (Mob Active Limit) float 0
+
+#    Enables area check when spawning mobs
+mob_area_spawn (Mob Area Spawn) bool false