diff --git a/not-gloss-examples.cabal b/not-gloss-examples.cabal
--- a/not-gloss-examples.cabal
+++ b/not-gloss-examples.cabal
@@ -1,5 +1,5 @@
 name:                not-gloss-examples
-version:             0.2
+version:             0.2.1
 stability:           Experimental
 synopsis:            examples for not-gloss
 license:             BSD3
@@ -13,28 +13,28 @@
 
 executable           not-gloss-display
   main-is:           src/Display.hs
-  build-depends:     not-gloss == 0.4.*,
+  build-depends:     not-gloss >= 0.4.1,
                      spatial-math >= 0.1.4 && < 0.2,
                      base == 4.5.*
   ghc-options:       -threaded -O2
 
 executable           not-gloss-animate
   main-is:           src/Animate.hs
-  build-depends:     not-gloss == 0.4.*,
+  build-depends:     not-gloss >= 0.4.1,
                      spatial-math >= 0.1.4 && < 0.2,
                      base == 4.5.*
   ghc-options:       -threaded -O2
 
 executable           not-gloss-simulate
   main-is:           src/Simulate.hs
-  build-depends:     not-gloss == 0.4.*,
+  build-depends:     not-gloss >= 0.4.1,
                      spatial-math >= 0.1.4 && < 0.2,
                      base == 4.5.*
   ghc-options:       -threaded -O2
 
 executable           not-gloss-game
   main-is:           src/Play.hs
-  build-depends:     not-gloss == 0.4.*,
+  build-depends:     not-gloss >= 0.4.1,
                      spatial-math >= 0.1.4 && < 0.2,
                      GLUT == 2.3.*,
                      containers == 0.4.*,
diff --git a/src/Simulate.hs b/src/Simulate.hs
--- a/src/Simulate.hs
+++ b/src/Simulate.hs
@@ -10,15 +10,19 @@
 ts :: Double
 ts = 0.01
 
-data State a = State (a,a) (Quat a)
+data State a = State (a,a) (Quat a) [Xyz a]
 
 simFun :: Float -> State Double -> State Double
-simFun _ (State (x,v) q0) = State (x + v*ts, v + 5*ts*(-1 - x)) (Quat.qmult' q0 dq)
+simFun _ (State (x0,v) q0 trail0) = State (x, v + 5*ts*(-1 - x)) (Quat.qmult' q0 dq) trail
   where
     dq = Quat 1 (x*ts) (v*ts) (x*v*ts)
+    x = x0 + v*ts
+    trail
+      | length trail0 < 75 = (Xyz 0 x (-1)):trail0
+      | otherwise = take 75 ((Xyz 0 x (-1)):trail0)
 
 drawFun :: State Double -> VisObject Double
-drawFun (State (x,_) quat) = VisObjects $ [axes,box,ellipsoid,sphere] ++ (map text [-5..5]) ++ [boxText, plane] 
+drawFun (State (x,_) quat trail) = VisObjects $ [axes,box,ellipsoid,sphere, line] ++ (map text [-5..5]) ++ [boxText, plane] 
   where
     axes = VisAxes (0.5, 15) (Xyz 0 0 0) (Quat 1 0 0 0)
     sphere = VisSphere 0.15 (Xyz 0 x (-1)) Wireframe (makeColor 0.2 0.3 0.8 1)
@@ -29,8 +33,12 @@
       where
         x' = realToFrac $ (x + 1)/0.4*k/5
     boxText = Vis3dText "trololololo" (Xyz 0 0 (x-0.2)) TimesRoman24 (makeColor 1 0 0 1)
+    line = VisLine' $ zip trail (map (\a -> makeColor 1 0 0 a) (linspace 1 0 (length trail))) -- (makeColor 1 0 0 1)
 
+linspace :: Fractional a => a -> a -> Int -> [a]
+linspace x0 xf n = map (\k -> x0 + (xf - x0) * (fromIntegral k) / (fromIntegral n-1)) [0..(n-1)]
+
 main :: IO ()
 main = do
-  let state0 = State (-1.4,0) (Quat 1 0 0 0)
+  let state0 = State (-1.4,0) (Quat 1 0 0 0) []
   simulate ts state0 drawFun simFun