Add in swap_y_with_x and reverse_head_yaw to flesh out head code api element

mods/ENTITIES/mcl_mobs/api/api.lua

@@ -371,6 +371,12 @@ function mobs:register_mob(name, def)
 		has_head = def.has_head or false,
 		head_bone = def.head_bone,
 
+		--you must use these to adjust the mob's head positions
+		head_bone_pos_y = def.head_bone_pos_y or 3.6,
+		head_bone_pos_z = def.head_bone_pos_z or -0.6,
+		swap_y_with_x = def.swap_y_with_x or false,
+		reverse_head_yaw = def.reverse_head_yaw or false,
+
 		--end j4i stuff
 
 		-- MCL2 extensions

mods/ENTITIES/mcl_mobs/api/mob_functions/head_logic.lua

@@ -54,13 +54,11 @@ mobs.do_head_logic = function(self,dtime)
 
     --needs to be INTERNAL (API)
     --(horizontal)
-    self.head_bone_pos_y = 3.6
     bone_pos.y = self.head_bone_pos_y
 
     
     --needs to be INTERNAL (API)
     --(vertical)
-    self.head_bone_pos_z = -0.6
     bone_pos.z = self.head_bone_pos_z
 
     --print(yaw)
@@ -70,10 +68,13 @@ mobs.do_head_logic = function(self,dtime)
     --bone_rot.x = bone_rot.x + (dtime * 10)
     --bone_rot.z = bone_rot.z + (dtime * 10)
 
-    local head_yaw
 
+    local head_yaw 
     head_yaw = minetest.dir_to_yaw(vector.direction(pos,look_at)) - body_yaw
 
+    if self.reverse_head_yaw then
+        head_yaw = head_yaw * -1
+    end
 
     --over rotation protection
     --stops radians from going out of spec
@@ -105,8 +106,11 @@ mobs.do_head_logic = function(self,dtime)
         head_pitch = minetest.dir_to_yaw(vector.new(vector.distance(vector.new(pos.x,0,pos.z),vector.new(look_at.x,0,look_at.z)),0,pos.y-look_at.y))+(math.pi/2)
     end
 
-    self.object:set_bone_position("head", bone_pos, vector_new(degrees(head_pitch),0,degrees(head_yaw)))
-
+    if self.swap_y_with_x then
+        self.object:set_bone_position("head", bone_pos, vector_new(degrees(head_pitch),degrees(head_yaw),0))
+    else
+        self.object:set_bone_position("head", bone_pos, vector_new(degrees(head_pitch),0,degrees(head_yaw)))
+    end
 
 
     --set_bone_position([bone, position, rotation])

mods/ENTITIES/mobs_mc/creeper.lua

@@ -53,6 +53,10 @@ mobs:register_mob("mobs_mc:creeper", {
 	allow_fuse_reset = true,
 	stop_to_explode = true,
 
+	--head code
+	swap_y_with_x = true,
+	reverse_head_yaw = true,
+
 	-- Force-ignite creeper with flint and steel and explode after 1.5 seconds.
 	-- TODO: Make creeper flash after doing this as well.
 	-- TODO: Test and debug this code.