diff --git a/Lasers_und_stuff/main.py b/Lasers_und_stuff/main.py
index 71825e9..bd5adcb 100644
--- a/Lasers_und_stuff/main.py
+++ b/Lasers_und_stuff/main.py
@@ -81,7 +81,14 @@ def main():
                     if "Laser disabled" in screen.communicates :
                         screen.communicates.remove("Laser disabled")
                     screen.communicates.append("Laser enabled")
-                    
+            elif event.type == KEYUP and event.key == K_c:   
+                point1 = [float(x) for x in ask(window, "Point 1 ").split(",")]
+                point2 = [float(x) for x in ask(window, "Point 2 ").split(",")]
+                point3 = [float(x) for x in ask(window, "Point 3 ").split(",")]
+                print point1, point2, point3
+                gunpoint.calibrate(point1, point2, point3)
+                print gunpoint.horizontal_angle, gunpoint.vertical_angle
+ 
             elif event.type == MOUSEBUTTONUP:
                 print "mouse button up"
                 mouseClicked = True
@@ -96,14 +103,56 @@ def main():
             print samples
             print coords
             
+            
 
 
+def get_key():
+    while 1:
+        event = pygame.event.poll()
+        if event.type == KEYDOWN:
+            return event.key
+        else:
+            pass
+
+def display_box(screen, message, xx, yy):
+    "Print a message in a box in the middle of the screen"
+    font_object = pygame.font.Font(None,18)
+    pygame.draw.rect(screen, (0,0,0),(xx, yy, 200,20), 0)
+    pygame.draw.rect(screen, (255,255,255),
+                    (xx -2, yy-2, 202,24), 1)
+                   
+    if len(message) != 0:
+        screen.blit(font_object.render(message, 1, (255,255,255)),
+                (xx + 6, yy + 6) )
+    
+    pygame.display.flip()
+
+def ask(screen, question):
+    "ask(screen, question) -> answer"
+    pygame.font.init()
+    current_string = []
+    display_box(screen, question + ": " + "".join(current_string), 20, 400)
+    while 1:
+        inkey = get_key()
+        if inkey == K_BACKSPACE:
+            current_string = current_string[0:-1]
+        elif inkey == K_RETURN:
+            break
+        elif inkey == K_MINUS:
+            current_string.append("_")
+        elif inkey <= 127:
+            current_string.append(chr(inkey))
+        display_box(screen, question + ": " + "".join(current_string), 20, 400)
+    return "".join(current_string)
+  
+  
 class Screen:
     
     def __init__(self, window, colors):
         self.communicates = []
         self.communicates.append("Press space to fire!")
         self.communicates.append("Use arrows to adjust position")
+        self.communicates.append("Press C for calibration")
         self.communicates.append("Press L to enable laser")
         self.window = window
         self.colors = colors
@@ -118,7 +167,7 @@ class Screen:
             self.print_text(text, 20, 20 + i*20, (0, 0, 0), 20, self.window)
         
         if cannon.fired:
-            self.print_text("Fired!", 20, 100, (150, 20, 40), 40, self.window) 
+            self.print_text("Fired!", 20, 150, (150, 20, 40), 40, self.window) 
         
         self.print_text(cannon.get_data_to_send().__str__(), 20, 300, (0, 0, 0), 30, self.window)               
         pygame.display.flip() 
@@ -186,6 +235,12 @@ class Gunpoint :
         self.beginnig_horizontal = point1[0]
         self.beginnig_vertical = point1[1]
         
+    def calibrate(self, point1, point2, point3):
+        self.vertical_angle = point3[1] - point1[1]
+        self.horizontal_angle = point2[0] - point1[0]
+        self.beginnig_horizontal = point1[0]
+        self.beginnig_vertical = point1[1]
+        
     def aim(self, point):
         horizontal = ceil(self.beginnig_horizontal + self.horizontal_angle*point[0])
         vertical = ceil(self.beginnig_vertical + self.vertical_angle*point[1])