Fixed font 9x15 supported.

The function text allows to display multiple strings, which are placed among
each other.

Main.hs

@@ -29,16 +29,19 @@ main = do
                     vertex $ Vertex3 0.65 (0.65 :: GLfloat) 0.0
                     vertex $ Vertex3 x y 0.0
             -}
-
+
+            color $ Color3 0 1 (1 :: GLdouble)
+            text (0.65, 0.95) (map show [(1 :: Int)..10])
+
             -- Rectangle
             color $ Color3 1 0 (0 :: GLdouble)
             renderPrimitive LineLoop $ do
                 let f (x,y) = vertex $ Vertex3 x (y :: GLfloat) 0.0
                 mapM_ f [
                     (0.00, 0.00)
                   , (1.30, 0.00)
-                  , (1.30, 1.30)
-                  , (0.00, 1.30)]
+                  , (1.30, 1.00)
+                  , (0.00, 1.00)]
 
         -- KEY
       , keyHandler   = Just $ KeyHandler $ \key state _ -> 

Window.hs

@@ -17,6 +17,7 @@ module Window (
   , Image(..)
   , loadImage
   , drawImage
+  , text
 ) where
 
 import Control.Concurrent
@@ -218,3 +219,17 @@ drawImage (Image obj path) = do
         toVertex (x,y) = vertex $ Vertex2 x y
 
 
+text :: (GLfloat, GLfloat) -> [String] -> IO ()
+text (x,y) ss' = do
+    -- Handle different window sizes correctly by calculating the space between
+    -- subsequent lines:
+    Size _ wh <- get windowSize
+    fs        <- (*1.5) `liftM` fontHeight Fixed9By15
+    render (fs / fromIntegral wh) y ss'
+  where render _ _ []      = return ()
+        render h y' (s:ss) = do
+            print y'
+            rasterPos $ Vertex3 x y' 0.0
+            renderString Fixed8By13 s
+            render h (y'-h) ss
+