X.L.ThreeColumnsMiddle merged into X.L.ThreeColumns with some new features

Ignore-this: 1d5bb8de98f8ade3780444ed99f5a12f

darcs-hash:20090411113636-8978f-e970950394e38cbd72d8ada44c62cac0934234d7.gz

1 files changed, 42 insertions, 25 deletions

diff --git a/XMonad/Layout/ThreeColumns.hs b/XMonad/Layout/ThreeColumns.hs
index 188bce9..06eb943 100644
--- a/XMonad/Layout/ThreeColumns.hs
+++ b/XMonad/Layout/ThreeColumns.hs
@@ -10,7 +10,11 @@
 -- Stability   :  unstable
 -- Portability :  unportable
 --
--- A layout similar to tall but with three columns.
+-- A layout similar to tall but with three columns. With 2560x1600 pixels this
+-- layout can be used for a huge main window and up to six reasonable sized
+-- slave windows.
+--
+-- Screenshot: <http://server.c-otto.de/xmonad/ThreeColumnsMiddle.png>
 --
 -----------------------------------------------------------------------------
 
@@ -34,44 +38,57 @@ import Control.Monad
 --
 -- Then edit your @layoutHook@ by adding the ThreeCol layout:
 --
--- > myLayouts = ThreeCol 1 (3/100) (1/2) ||| etc..
+-- > myLayouts = ThreeCol False 1 (3/100) (1/2) ||| etc..
 -- > main = xmonad defaultConfig { layoutHook = myLayouts }
 --
+-- If the first argument is true, the main window is placed in the center
+-- column. The second argument specifies hom many windows initially appear in
+-- the main window. The third argument argument specifies the amount to resize
+-- while resizing and the fourth argument specifies the initial size of the
+-- columns. A positive size designates the fraction of the screen that the main
+-- window should occupy, but if the size is negative the absolute value
+-- designates the fraction a slave column should occupy. If both slave columns
+-- are visible, they always occupy the same amount of space.
+--
 -- For more detailed instructions on editing the layoutHook see:
 --
 -- "XMonad.Doc.Extending#Editing_the_layout_hook"
 
-data ThreeCol a = ThreeCol !Int !Rational !Rational deriving (Show,Read)
+data ThreeCol a = ThreeCol !Bool !Int !Rational !Rational deriving (Show,Read)
 
 instance LayoutClass ThreeCol a where
-    doLayout (ThreeCol nmaster _ frac) r =
+    doLayout (ThreeCol middle nmaster _ frac) r =
         return . (\x->(x,Nothing)) .
-        ap zip (tile3 frac r nmaster . length) . W.integrate
-    handleMessage (ThreeCol nmaster delta frac) m =
+        ap zip (tile3 middle frac r nmaster . length) . W.integrate
+    handleMessage (ThreeCol middle nmaster delta frac) m =
         return $ msum [fmap resize     (fromMessage m)
                       ,fmap incmastern (fromMessage m)]
-            where resize Shrink = ThreeCol nmaster delta (max 0 $ frac-delta)
-                  resize Expand = ThreeCol nmaster delta (min 1 $ frac+delta)
-                  incmastern (IncMasterN d) = ThreeCol (max 0 (nmaster+d)) delta frac
+            where resize Shrink = ThreeCol middle nmaster delta (max (-0.5) $ frac-delta)
+                  resize Expand = ThreeCol middle nmaster delta (min 1 $ frac+delta)
+                  incmastern (IncMasterN d) = ThreeCol middle (max 0 (nmaster+d)) delta frac
     description _ = "ThreeCol"
 
 -- | tile3.  Compute window positions using 3 panes
-tile3 :: Rational -> Rectangle -> Int -> Int -> [Rectangle]
-tile3 f r nmaster n 
+tile3 :: Bool -> Rational -> Rectangle -> Int -> Int -> [Rectangle]
+tile3 middle f r nmaster n
     | n <= nmaster || nmaster == 0 = splitVertically n r
     | n <= nmaster+1 = splitVertically nmaster s1 ++ splitVertically (n-nmaster) s2
-    | otherwise = splitVertically nmaster r1 ++ splitVertically nmid r2 ++ splitVertically nright r3
-  where (r1, r2, r3) = split3HorizontallyBy f r
-        (s1, s2) = splitHorizontallyBy f r
-        nslave = (n - nmaster)
-        nmid = ceiling (nslave % 2)
-        nright = (n - nmaster - nmid)
+    | otherwise = splitVertically nmaster r1 ++ splitVertically nslave1 r2 ++ splitVertically nslave2 r3
+        where (r1, r2, r3) = split3HorizontallyBy middle (if f<0 then 1+2*f else f) r
+              (s1, s2) = splitHorizontallyBy (if f<0 then 1+f else f) r
+              nslave = (n - nmaster)
+              nslave1 = ceiling (nslave % 2)
+              nslave2 = (n - nmaster - nslave1)
 
-split3HorizontallyBy :: Rational -> Rectangle -> (Rectangle, Rectangle, Rectangle)
-split3HorizontallyBy f (Rectangle sx sy sw sh) =
-    ( Rectangle sx sy leftw sh
-    , Rectangle (sx + fromIntegral leftw) sy midw sh
-    , Rectangle (sx + fromIntegral leftw + fromIntegral midw) sy rightw sh )
-  where leftw = ceiling $ fromIntegral sw * (2/3) * f
-        midw = ceiling ( (sw - leftw) % 2 )
-        rightw = sw - leftw - midw
+split3HorizontallyBy :: Bool -> Rational -> Rectangle -> (Rectangle, Rectangle, Rectangle)
+split3HorizontallyBy middle f (Rectangle sx sy sw sh) =
+    if middle
+    then ( Rectangle (sx + fromIntegral r2w) sy r1w sh
+         , Rectangle sx sy r2w sh
+         , Rectangle (sx + fromIntegral r2w + fromIntegral r1w) sy r3w sh )
+    else ( Rectangle sx sy r1w sh
+         , Rectangle (sx + fromIntegral r1w) sy r2w sh
+         , Rectangle (sx + fromIntegral r1w + fromIntegral r2w) sy r3w sh )
+        where r1w = ceiling $ fromIntegral sw * f
+              r2w = ceiling ( (sw - r1w) % 2 )
+              r3w = sw - r1w - r2w