diff --git a/src/physics_entity.h b/src/physics_entity.h
index ea0abf9..1f12fa5 100644
--- a/src/physics_entity.h
+++ b/src/physics_entity.h
@@ -10,24 +10,25 @@
 typedef struct {
     RigidBody* (*const get_rigidbody)(void* self);
     Shape* (*const get_shape)(void* self);
-    Transformable (*const as_transformable)(void* self);
 } IPhysicsEntity;
 
 typedef struct {
-    void* self;
+    void* data;
     IPhysicsEntity const* tc;
+    ITransformable const* transformable;
 } PhysicsEntity;
 
 #define impl_PhysicsEntity_for(T, get_rigidbody_f, get_shape_f)\
 static inline PhysicsEntity T##_as_PhysicsEntity(T* x) {\
-    TC_FN_TYPECHECK(RigidBody*, get_rigidbody_f, T* e);\
-    TC_FN_TYPECHECK(Shape*, get_shape_f, T* e);\
+    TC_FN_TYPECHECK(Transformable, T##_as_Transformable, T*);\
+    TC_FN_TYPECHECK(RigidBody*, get_rigidbody_f, T*);\
+    TC_FN_TYPECHECK(Shape*, get_shape_f, T*);\
     static IPhysicsEntity const tc = {\
-        .get_rigidbody =     (RigidBody*(*const)(void*))  get_transform_f,\
+        .get_rigidbody =     (RigidBody*(*const)(void*))  get_rigidbody_f,\
         .get_shape =         (Shape*(*const)(void*))      get_shape_f,\
-        .as_transformable =  T##_as_Transformable\
     };\
-    return (PhysicsEntity){.tc = &interface, .self = x};\
+    Transformable transformable = T##_as_Transformable(x);\
+    return (PhysicsEntity){.data = x, .tc = &tc, .transformable = transformable.tc};\
 }
 
 #endif // !_fencer_collidable_h