Tony Zorman 4a3f8eb032 X.U.Font: Add a fallback font to initXMF
In case a font could not be opened, simply fall back to "xft:monospace"
and open that.  The initCoreFont and initUtf8Font functions already have
mechanisms like this, is was just missing from initXMF.

Closes: https://github.com/xmonad/xmonad-contrib/issues/723
2022-09-15 19:02:26 +02:00

242 lines
8.1 KiB
Haskell

{-# LANGUAGE CPP #-}
----------------------------------------------------------------------------
-- |
-- Module : XMonad.Util.Font
-- Description : A module for abstracting a font facility over Core fonts and Xft.
-- 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
, pixelToString
, fi
) where
import XMonad
import XMonad.Prelude
import Foreign
import Control.Exception as E
import Text.Printf (printf)
#ifdef XFT
import qualified Data.List.NonEmpty as NE
import Graphics.X11.Xrender
import Graphics.X11.Xft
#endif
-- Hide the Core Font/Xft switching here
data XMonadFont = Core FontStruct
| Utf8 FontSet
#ifdef XFT
| Xft (NE.NonEmpty 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)
-- | Convert a @Pixel@ into a @String@.
--
-- This function removes any alpha channel from the @Pixel@, because X11
-- mishandles alpha channels and produces black.
pixelToString :: (MonadIO m) => Display -> Pixel -> m String
pixelToString d p = do
let cm = defaultColormap d (defaultScreen d)
(Color _ r g b _) <- io (queryColor d cm $ Color (p .&. 0x00FFFFFF) 0 0 0 0)
return ("#" ++ hex r ++ hex g ++ hex b)
where
-- NOTE: The @Color@ type has 16-bit values for red, green, and
-- blue, even though the actual type in X is only 8 bits wide. It
-- seems that the upper and lower 8-bit sections of the @Word16@
-- values are the same. So, we just discard the lower 8 bits.
--
-- (Strictly, X11 supports 16-bit values but no visual supported
-- by XOrg does. It is still correct to discard the lower bits, as
-- they are not guaranteed to be meaningful in such visuals.)
hex = printf "%02x" . (`shiftR` 8)
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 $ E.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 $ E.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 =
#ifndef XFT
Utf8 <$> initUtf8Font s
#else
if xftPrefix `isPrefixOf` s then
do dpy <- asks display
let fonts = case wordsBy (== ',') (drop (length xftPrefix) s) of
[] -> fallback :| [] -- NE.singleton only in base 4.15
(x : xs) -> x :| xs
fb <- io $ openFont dpy fallback
fmap Xft . io $ traverse (\f -> E.catch (openFont dpy f) (econst $ pure fb))
fonts
else Utf8 <$> initUtf8Font s
where
xftPrefix = "xft:"
fallback = "xft:monospace"
openFont dpy str = xftFontOpen dpy (defaultScreenOfDisplay dpy) str
wordsBy p str = case dropWhile p str of
"" -> []
str' -> w : wordsBy p str''
where (w, str'') = break p str'
#endif
releaseXMF :: XMonadFont -> X ()
#ifdef XFT
releaseXMF (Xft xftfonts) = do
dpy <- asks display
io $ mapM_ (xftFontClose dpy) xftfonts
#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
#if MIN_VERSION_X11_xft(0, 3, 4)
gi <- xftTextAccumExtents dpy (toList xftdraw) s
#else
gi <- xftTextExtents dpy (NE.head xftdraw) s
#endif
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
#if MIN_VERSION_X11_xft(0, 3, 4)
textExtentsXMF (Xft xftfonts) _ = io $ do
ascent <- fi <$> xftfont_max_ascent xftfonts
descent <- fi <$> xftfont_max_descent xftfonts
#else
textExtentsXMF (Xft xftfonts) _ = io $ do
ascent <- fi <$> xftfont_ascent (NE.head xftfonts)
descent <- fi <$> xftfont_descent (NE.head xftfonts)
#endif
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 fonts) 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
#if MIN_VERSION_X11_xft(0, 3, 4)
gi <- io $ xftTextAccumExtents dpy (toList fonts) s
#else
gi <- io $ xftTextExtents dpy (NE.head fonts) s
#endif
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 $
#if MIN_VERSION_X11_xft(0, 3, 4)
\color -> xftDrawStringFallback draw color (toList fonts) (fi x) (fi y) s
#else
\color -> xftDrawString draw color (NE.head fonts) x y s
#endif
#endif