module XMonad.Layout.Grid (
Grid(..), arrange
) where
import XMonad
import XMonad.StackSet
data Grid a = Grid deriving (Read, Show)
instance LayoutClass Grid a where
pureLayout Grid r s = arrange r (integrate s)
arrange :: Rectangle -> [a] -> [(a, Rectangle)]
arrange (Rectangle rx ry rw rh) st = zip st rectangles
where
nwins = length st
ncols = max 1 . round . sqrt $ fromIntegral nwins * 9 * fromIntegral rw / (16 * fromIntegral rh :: Double)
mincs = nwins `div` ncols
extrs = nwins ncols * mincs
chop :: Int -> Dimension -> [(Position, Dimension)]
chop n m = ((0, m k * fromIntegral (pred n)) :) . map (flip (,) k) . tail . reverse . take n . tail . iterate (subtract k') $ m'
where
k :: Dimension
k = m `div` fromIntegral n
m' = fromIntegral m
k' :: Position
k' = fromIntegral k
xcoords = chop ncols rw
ycoords = chop mincs rh
ycoords' = chop (succ mincs) rh
(xbase, xext) = splitAt (ncols extrs) xcoords
rectangles = combine ycoords xbase ++ combine ycoords' xext
where
combine ys xs = [Rectangle (rx + x) (ry + y) w h | (x, w) <- xs, (y, h) <- ys]