aboutsummaryrefslogtreecommitdiffstats
path: root/XMonad/Util/Font.hs
blob: ed09a6d1a75a4016ae203c0d87389ddff17c74a9 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
{-# LANGUAGE CPP #-}
----------------------------------------------------------------------------
-- |
-- Module      :  XMonad.Util.Font
-- Copyright   :  (c) 2007 Andrea Rossato and Spencer Janssen
-- License     :  BSD-style (see xmonad/LICENSE)
--
-- Maintainer  :  andrea.rossato@unibz.it
-- Stability   :  unstable
-- Portability :  unportable
--
-- A module for abstracting a font facility over Core fonts and Xft
--
-----------------------------------------------------------------------------

module XMonad.Util.Font
    ( -- * Usage:
      -- $usage
      XMonadFont(..)
    , initXMF
    , releaseXMF
    , initCoreFont
    , releaseCoreFont
    , initUtf8Font
    , releaseUtf8Font
    , Align (..)
    , stringPosition
    , textWidthXMF
    , textExtentsXMF
    , printStringXMF
    , stringToPixel
    , fi
    ) where

import Prelude hiding (catch)
import XMonad
import Foreign
import Control.Applicative
import Control.Exception
import Data.Maybe

#ifdef XFT
import Data.List
import Graphics.X11.Xft
import Graphics.X11.Xrender
#endif

-- Hide the Core Font/Xft switching here
data XMonadFont = Core FontStruct
                | Utf8 FontSet
#ifdef XFT
                | Xft  XftFont
#endif

-- $usage
-- See "Xmonad.Layout.Tabbed" or "XMonad.Prompt" for usage examples

-- | Get the Pixel value for a named color: if an invalid name is
-- given the black pixel will be returned.
stringToPixel :: (Functor m, MonadIO m) => Display -> String -> m Pixel
stringToPixel d s = fromMaybe fallBack <$> io getIt
    where getIt    = initColor d s
          fallBack = blackPixel d (defaultScreen d)

econst :: a -> IOException -> a
econst = const

-- | Given a fontname returns the font structure. If the font name is
--  not valid the default font will be loaded and returned.
initCoreFont :: String -> X FontStruct
initCoreFont s = do
  d <- asks display
  io $ catch (getIt d) (fallBack d)
      where getIt    d = loadQueryFont d s
            fallBack d = econst $ loadQueryFont d "-misc-fixed-*-*-*-*-10-*-*-*-*-*-*-*"

releaseCoreFont :: FontStruct -> X ()
releaseCoreFont fs = do
  d <- asks display
  io $ freeFont d fs

initUtf8Font :: String -> X FontSet
initUtf8Font s = do
  d <- asks display
  (_,_,fs) <- io $ catch (getIt d) (fallBack d)
  return fs
      where getIt    d = createFontSet d s
            fallBack d = econst $ createFontSet d "-misc-fixed-*-*-*-*-10-*-*-*-*-*-*-*"

releaseUtf8Font :: FontSet -> X ()
releaseUtf8Font fs = do
  d <- asks display
  io $ freeFontSet d fs

-- | When initXMF gets a font name that starts with 'xft:' it switches to the Xft backend
-- Example: 'xft: Sans-10'
initXMF :: String -> X XMonadFont
initXMF s =
#ifdef XFT
  if xftPrefix `isPrefixOf` s then
     do dpy <- asks display
        xftdraw <- io $ xftFontOpen dpy (defaultScreenOfDisplay dpy) (drop (length xftPrefix) s)
        return (Xft xftdraw)
  else
#endif
      fmap Utf8 $ initUtf8Font s
#ifdef XFT
  where xftPrefix = "xft:"
#endif

releaseXMF :: XMonadFont -> X ()
#ifdef XFT
releaseXMF (Xft xftfont) = do
  dpy <- asks display
  io $ xftFontClose dpy xftfont
#endif
releaseXMF (Utf8 fs) = releaseUtf8Font fs
releaseXMF (Core fs) = releaseCoreFont fs


textWidthXMF :: MonadIO m => Display -> XMonadFont -> String -> m Int
textWidthXMF _   (Utf8 fs) s = return $ fi $ wcTextEscapement fs s
textWidthXMF _   (Core fs) s = return $ fi $ textWidth fs s
#ifdef XFT
textWidthXMF dpy (Xft xftdraw) s = liftIO $ do
    gi <- xftTextExtents dpy xftdraw s
    return $ xglyphinfo_xOff gi
#endif

textExtentsXMF :: MonadIO m => XMonadFont -> String -> m (Int32,Int32)
textExtentsXMF (Utf8 fs) s = do
  let (_,rl)  = wcTextExtents fs s
      ascent  = fi $ - (rect_y rl)
      descent = fi $ rect_height rl + (fi $ rect_y rl)
  return (ascent, descent)
textExtentsXMF (Core fs) s = do
  let (_,a,d,_) = textExtents fs s
  return (a,d)
#ifdef XFT
textExtentsXMF (Xft xftfont) _ = io $ do
  ascent  <- fi `fmap` xftfont_ascent  xftfont
  descent <- fi `fmap` xftfont_descent xftfont
  return (ascent, descent)
#endif

-- | String position
data Align = AlignCenter | AlignRight | AlignLeft | AlignRightOffset Int
                deriving (Show, Read)

-- | Return the string x and y 'Position' in a 'Rectangle', given a
-- 'FontStruct' and the 'Align'ment
stringPosition :: (Functor m, MonadIO m) => Display -> XMonadFont -> Rectangle -> Align -> String -> m (Position,Position)
stringPosition dpy fs (Rectangle _ _ w h) al s = do
  width <- textWidthXMF dpy fs s
  (a,d) <- textExtentsXMF fs s
  let y = fi $ ((h - fi (a + d)) `div` 2) + fi a;
      x = case al of
            AlignCenter -> fi (w `div` 2) - fi (width `div` 2)
            AlignLeft   -> 1
            AlignRight  -> fi (w - (fi width + 1));
            AlignRightOffset offset -> fi (w - (fi width + 1)) - fi offset;
  return (x,y)

printStringXMF :: (Functor m, MonadIO m) => Display -> Drawable -> XMonadFont -> GC -> String -> String
            -> Position -> Position -> String  -> m ()
printStringXMF d p (Core fs) gc fc bc x y s = io $ do
    setFont d gc $ fontFromFontStruct fs
    [fc',bc'] <- mapM (stringToPixel d) [fc,bc]
    setForeground d gc fc'
    setBackground d gc bc'
    drawImageString d p gc x y s
printStringXMF d p (Utf8 fs) gc fc bc x y s = io $ do
    [fc',bc'] <- mapM (stringToPixel d) [fc,bc]
    setForeground d gc fc'
    setBackground d gc bc'
    io $ wcDrawImageString d p fs gc x y s
#ifdef XFT
printStringXMF dpy drw fs@(Xft font) gc fc bc x y s = do
  let screen   = defaultScreenOfDisplay dpy
      colormap = defaultColormapOfScreen screen
      visual   = defaultVisualOfScreen screen
  bcolor <- stringToPixel dpy bc
  (a,d)  <- textExtentsXMF fs s
  gi <- io $ xftTextExtents dpy font s
  io $ setForeground dpy gc bcolor
  io $ fillRectangle dpy drw gc (x - fi (xglyphinfo_x gi))
                                (y - fi a)
                                (fi $ xglyphinfo_xOff gi)
                                (fi $ a + d)
  io $ withXftDraw dpy drw visual colormap $
         \draw -> withXftColorName dpy visual colormap fc $
                   \color -> xftDrawString draw color font x y s
#endif

-- | Short-hand for 'fromIntegral'
fi :: (Integral a, Num b) => a -> b
fi = fromIntegral