diff --git a/main.py b/main.py
index ec86a30..2ef4987 100644
--- a/main.py
+++ b/main.py
@@ -41,7 +41,7 @@ class Cross_painter(Widget):
     def on_touch_down(self,touch):
         # create new cross
         if touch.button=="right":
-            if self.check_add((touch.x,touch.y)):
+            if self.check_add(Point(touch.x,touch.y)):
                 new=Cross(touch.x,touch.y)
                 with self.canvas:
                     new.draw()
@@ -91,7 +91,7 @@ class Cross_painter(Widget):
     # check that a cross can be added at position
     def check_add(self,pos):
         for cross in self.crosses:
-            if self.check_interaction(pos,cross)==False:
+            if cross.check_interaction(pos)==False:
                 return False
         return True