diff --git a/pmc/include/drawable.h b/pmc/include/drawable.h
--- a/pmc/include/drawable.h
+++ b/pmc/include/drawable.h
@@ -11,12 +11,12 @@
 
 class Drawable:public Object {
   protected:
-    Vector anker;
+    algebra::Vector anker;
     Surface *surface;
 
   public:
-    virtual ~ Drawable () {};
-    virtual void move (Vector) = 0;
+    virtual ~ Drawable () { };
+    virtual void move (algebra::Vector) = 0;
     virtual void show () = 0;
 };
 #endif