diff --git a/Gtk.hs b/Gtk.hs
new file mode 100644
index 0000000..90d57b0
--- /dev/null
+++ b/Gtk.hs
@@ -0,0 +1,125 @@
+module Gtk where
+
+import Control.Monad.IO.Class
+import Diagram
+import Diagrams.Prelude
+import Diagrams.Backend.Cairo
+import Diagrams.Backend.Cairo.Internal
+import Graphics.UI.Gtk
+import Graphics.UI.Gtk.Windows.MessageDialog
+import System.Directory
+
+
+startGUI :: IO ()
+startGUI = do
+  homedir <- getHomeDirectory
+
+  -- init gui
+  _ <- initGUI
+
+  -- create window and widgets
+  window          <- windowNew
+  da              <- drawingAreaNew
+  fileButton      <- fileChooserButtonNew "Select mesh"
+                     FileChooserActionOpen
+  drawButton      <- buttonNew
+  saveButton      <- buttonNew
+  quitButton      <- buttonNew
+  box1 <- vBoxNew False 0
+  box2 <- hButtonBoxNew
+  box3 <- hButtonBoxNew
+  drawButtonLabel <- labelNew $ Just "Draw"
+  saveButtonLabel <- labelNew $ Just "Save"
+  quitButtonLabel <- labelNew $ Just "Quit"
+
+  -- containers and boxing
+  containerAdd drawButton drawButtonLabel
+  containerAdd saveButton saveButtonLabel
+  containerAdd quitButton quitButtonLabel
+  containerAdd window box1
+  boxPackStart box1 da PackGrow 0
+  boxPackStart box1 box2 PackNatural 0
+  boxPackStart box1 box3 PackNatural 0
+  boxPackStart box2 drawButton PackNatural 0
+  boxPackStart box2 saveButton PackNatural 0
+  boxPackStart box2 quitButton PackNatural 0
+  boxPackStart box3 fileButton PackNatural 0
+
+  -- adjust properties
+  set window [windowDefaultWidth := 600, windowDefaultHeight := 700,
+              windowTitle := "Computergrafik"]
+  set box2 [buttonBoxLayoutStyle := ButtonboxCenter]
+  set box3 [buttonBoxLayoutStyle := ButtonboxCenter]
+  _ <- windowSetTypeHint window WindowTypeHintDialog
+  containerSetBorderWidth box2 10
+  _ <- fileChooserSetCurrentFolder fileButton homedir
+
+  -- callbacks
+  _ <- onDestroy window mainQuit
+  _ <- onClicked drawButton $ onClickedDrawButton fileButton
+                                                  da
+  _ <- onClicked saveButton $ onClickedSaveButton fileButton
+  _ <- onClicked quitButton mainQuit
+
+  -- hotkeys
+  _ <- window `on` keyPressEvent $ tryEvent $ do
+         [Control] <- eventModifier
+         "q"       <- eventKeyName
+         liftIO $ mainQuit
+  _ <- window `on` keyPressEvent $ tryEvent $ do
+         [Control] <- eventModifier
+         "s"       <- eventKeyName
+         liftIO $ onClickedSaveButton fileButton
+  _ <- window `on` keyPressEvent $ tryEvent $ do
+         [Control] <- eventModifier
+         "d"       <- eventKeyName
+         liftIO $ onClickedDrawButton fileButton da
+
+  -- draw widgets and start main loop
+  widgetShowAll window
+  mainGUI
+
+
+onClickedDrawButton :: WidgetClass widget
+                    => FileChooserButton
+                    -> widget
+                    -> IO ()
+onClickedDrawButton fcb da = do
+  filename <- fileChooserGetFilename fcb
+  case filename of
+    Just x -> do
+      mesh <- readFile x
+      dw   <- widgetGetDrawWindow da
+      let (_, r) = renderDia Cairo
+                     (CairoOptions "" (Width 600) SVG False)
+                     (diagFromString mesh)
+      renderWithDrawable dw r
+    Nothing -> do
+      showErrorDialog "No valid Mesh file!"
+
+
+onClickedSaveButton :: FileChooserButton
+                    -> IO ()
+onClickedSaveButton fcb = do
+  filename <- fileChooserGetFilename fcb
+  case filename of
+    Just x -> do
+      mesh <- readFile x
+      let (png, _) = renderDia Cairo
+                       (CairoOptions "out.svg" (Width 600) SVG False)
+                       (diagFromString mesh)
+      png
+    Nothing -> do
+      showErrorDialog "No valid Mesh file!"
+
+
+showErrorDialog :: String -> IO ()
+showErrorDialog str = do
+  errorDialog <- messageDialogNew Nothing
+                                  [DialogDestroyWithParent]
+                                  MessageError
+                                  ButtonsClose
+                                  str
+  _ <- dialogRun errorDialog
+  widgetDestroy errorDialog
+
diff --git a/Main.hs b/Main.hs
index 0284a13..afbd2aa 100644
--- a/Main.hs
+++ b/Main.hs
@@ -1,122 +1,4 @@
-import Control.Monad.IO.Class
-import Diagram
-import Diagrams.Prelude
-import Diagrams.Backend.Cairo
-import Diagrams.Backend.Cairo.Internal
-import Graphics.UI.Gtk
-import Graphics.UI.Gtk.Windows.MessageDialog
-import System.Directory
-
+import Gtk
 
 main :: IO ()
-main = do
-  homedir <- getHomeDirectory
-
-  -- init gui
-  _ <- initGUI
-
-  -- create window and widgets
-  window          <- windowNew
-  da              <- drawingAreaNew
-  fileButton      <- fileChooserButtonNew "Select mesh"
-                     FileChooserActionOpen
-  drawButton      <- buttonNew
-  saveButton      <- buttonNew
-  quitButton      <- buttonNew
-  box1 <- vBoxNew False 0
-  box2 <- hButtonBoxNew
-  box3 <- hButtonBoxNew
-  drawButtonLabel <- labelNew $ Just "Draw"
-  saveButtonLabel <- labelNew $ Just "Save"
-  quitButtonLabel <- labelNew $ Just "Quit"
-
-  -- containers and boxing
-  containerAdd drawButton drawButtonLabel
-  containerAdd saveButton saveButtonLabel
-  containerAdd quitButton quitButtonLabel
-  containerAdd window box1
-  boxPackStart box1 da PackGrow 0
-  boxPackStart box1 box2 PackNatural 0
-  boxPackStart box1 box3 PackNatural 0
-  boxPackStart box2 drawButton PackNatural 0
-  boxPackStart box2 saveButton PackNatural 0
-  boxPackStart box2 quitButton PackNatural 0
-  boxPackStart box3 fileButton PackNatural 0
-
-  -- adjust properties
-  set window [windowDefaultWidth := 600, windowDefaultHeight := 700,
-              windowTitle := "Computergrafik"]
-  set box2 [buttonBoxLayoutStyle := ButtonboxCenter]
-  set box3 [buttonBoxLayoutStyle := ButtonboxCenter]
-  _ <- windowSetTypeHint window WindowTypeHintDialog
-  containerSetBorderWidth box2 10
-  _ <- fileChooserSetCurrentFolder fileButton homedir
-
-  -- callbacks
-  _ <- onDestroy window mainQuit
-  _ <- onClicked drawButton $ onClickedDrawButton fileButton
-                                                  da
-  _ <- onClicked saveButton $ onClickedSaveButton fileButton
-  _ <- onClicked quitButton mainQuit
-
-  -- hotkeys
-  _ <- window `on` keyPressEvent $ tryEvent $ do
-         [Control] <- eventModifier
-         "q"       <- eventKeyName
-         liftIO $ mainQuit
-  _ <- window `on` keyPressEvent $ tryEvent $ do
-         [Control] <- eventModifier
-         "s"       <- eventKeyName
-         liftIO $ onClickedSaveButton fileButton
-  _ <- window `on` keyPressEvent $ tryEvent $ do
-         [Control] <- eventModifier
-         "d"       <- eventKeyName
-         liftIO $ onClickedDrawButton fileButton da
-
-  -- draw widgets and start main loop
-  widgetShowAll window
-  mainGUI
-
-
-onClickedDrawButton :: WidgetClass widget
-                    => FileChooserButton
-                    -> widget
-                    -> IO ()
-onClickedDrawButton fcb da = do
-  filename <- fileChooserGetFilename fcb
-  case filename of
-    Just x -> do
-      mesh <- readFile x
-      dw   <- widgetGetDrawWindow da
-      let (_, r) = renderDia Cairo
-                     (CairoOptions "" (Width 600) SVG False)
-                     (diagFromString mesh)
-      renderWithDrawable dw r
-    Nothing -> do
-      showErrorDialog "No valid Mesh file!"
-
-
-onClickedSaveButton :: FileChooserButton
-                    -> IO ()
-onClickedSaveButton fcb = do
-  filename <- fileChooserGetFilename fcb
-  case filename of
-    Just x -> do
-      mesh <- readFile x
-      let (png, _) = renderDia Cairo
-                       (CairoOptions "out.svg" (Width 600) SVG False)
-                       (diagFromString mesh)
-      png
-    Nothing -> do
-      showErrorDialog "No valid Mesh file!"
-
-
-showErrorDialog :: String -> IO ()
-showErrorDialog str = do
-  errorDialog <- messageDialogNew Nothing
-                                  [DialogDestroyWithParent]
-                                  MessageError
-                                  ButtonsClose
-                                  str
-  _ <- dialogRun errorDialog
-  widgetDestroy errorDialog
+main = startGUI