Disable backface_culling by default

API.txt

@@ -100,6 +100,7 @@ and with a chance of 100% 2 items of type "default:stone"
     textures = {"creatures_sheep.png"},  -- table of textures; see Minetest Documentation
     collisionbox = <NodeBox>,            -- defines mesh collision box; see Minetest Documentation
     rotation = 0.0,                      -- sets rotation offset when moving
+    backface_culling = false,            -- set true to enable backface culling
     animations = {                       -- animation used if defined <optional>
       idle = {#AnimationDef},            -- see #AnimationDef
         ... -- depends on modes (must correspond to be used); supported "special modes": eat, follow, attack

creatures/register.lua

@@ -33,6 +33,7 @@ local function translate_def(def)
   	textures = def.model.textures,
   	collisionbox = def.model.collisionbox or {-0.5, -0.5, -0.5, 0.5, 0.5, 0.5},
   	visual_size = def.model.scale or {x = 1, y = 1},
+    backface_culling = def.model.backface_culling or false
 
     stats = def.stats,
     model = def.model,