cairo: pure xlib/xft drawing code factored out

1 files changed, 234 insertions, 0 deletions

diff --git a/src/Xmobar/X11/XlibDraw.hs b/src/Xmobar/X11/XlibDraw.hs
new file mode 100644
index 0000000..3536791
--- /dev/null
+++ b/src/Xmobar/X11/XlibDraw.hs
@@ -0,0 +1,234 @@
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE TupleSections #-}
+
+------------------------------------------------------------------------------
+-- |
+-- Module: Xmobar.X11.XlibDraw
+-- Copyright: (c) 2018, 2020, 2022 Jose Antonio Ortega Ruiz
+-- License: BSD3-style (see LICENSE)
+--
+-- Maintainer: jao@gnu.org
+-- Stability: unstable
+-- Portability: portable
+-- Created: Sat Nov 24, 2018 18:49
+--
+--
+-- Drawing the xmobar contents using Xlib and Xft primitives
+--
+------------------------------------------------------------------------------
+
+
+module Xmobar.X11.XlibDraw (drawInPixmap) where
+
+import Prelude hiding (lookup)
+import Control.Monad.IO.Class
+import Control.Monad.Reader
+import Data.Map hiding ((\\), foldr, map, filter)
+import Data.List ((\\))
+import qualified Data.List.NonEmpty as NE
+
+import Graphics.X11.Xlib hiding (textExtents, textWidth, Segment)
+import Graphics.X11.Xlib.Extras
+
+import Xmobar.Config.Types
+import Xmobar.Run.Parsers hiding (parseString)
+import qualified Xmobar.X11.Bitmap as B
+import Xmobar.X11.Types
+import Xmobar.X11.Text
+import Xmobar.X11.ColorCache
+import Xmobar.X11.Window (drawBorder)
+import Xmobar.System.Utils (safeIndex)
+
+#ifdef XFT
+import Xmobar.X11.MinXft
+import Graphics.X11.Xrender
+#endif
+
+fi :: (Integral a, Num b) => a -> b
+fi = fromIntegral
+
+drawInPixmap :: GC -> Pixmap -> Dimension -> Dimension -> [[Segment]] -> X()
+drawInPixmap gc p wid ht ~[left,center,right] = do
+  r <- ask
+  let c = config r
+      d = display r
+      fs = fontListS r
+      vs = verticalOffsets r
+      strLn = liftIO . mapM getWidth
+      iconW i = maybe 0 B.width (lookup i $ iconS r)
+      getWidth (Text s,cl,i,_) =
+        textWidth d (safeIndex fs i) s >>= \tw -> return (Text s,cl,i,fi tw)
+      getWidth (Icon s,cl,i,_) = return (Icon s,cl,i,fi $ iconW s)
+      getWidth (Hspace s,cl,i,_) = return (Hspace s,cl,i,fi s)
+
+#if XFT
+  when (alpha c /= 255)
+     (liftIO $ drawBackground d p (bgColor c) (alpha c) (Rectangle 0 0 wid ht))
+#endif
+
+  withColors d [bgColor c, borderColor c] $ \[bgcolor, bdcolor] -> do
+#if XFT
+    when (alpha c == 255) $ do
+      liftIO $ setForeground d gc bgcolor
+      liftIO $ fillRectangle d p gc 0 0 wid ht
+#else
+    liftIO $ setForeground d gc bgcolor
+    liftIO $ fillRectangle d p gc 0 0 wid ht
+#endif
+    -- write to the pixmap the new string
+    printStrings p gc fs vs 1 L [] =<< strLn left
+    printStrings p gc fs vs 1 R [] =<< strLn right
+    printStrings p gc fs vs 1 C [] =<< strLn center
+    -- draw border if requested
+    liftIO $ drawBorder (border c) (borderWidth c) d p gc bdcolor wid ht
+
+verticalOffset :: (Integral b, Integral a, MonadIO m) =>
+                  a -> Widget -> XFont -> Int -> Config -> m b
+verticalOffset ht (Text t) fontst voffs _
+  | voffs > -1 = return $ fi voffs
+  | otherwise = do
+     (as,ds) <- liftIO $ textExtents fontst t
+     let margin = (fi ht - fi ds - fi as) `div` 2
+     return $ fi as + margin - 1
+verticalOffset ht (Icon _) _ _ conf
+  | iconOffset conf > -1 = return $ fi (iconOffset conf)
+  | otherwise = return $ fi (ht `div` 2) - 1
+verticalOffset _ (Hspace _) _ voffs _ = return $ fi voffs
+
+printString :: Display
+            -> Drawable
+            -> XFont
+            -> GC
+            -> String
+            -> String
+            -> Position
+            -> Position
+            -> Position
+            -> Position
+            -> String
+            -> Int
+            -> IO ()
+printString d p (Core fs) gc fc bc x y _ _ s a = do
+    setFont d gc $ fontFromFontStruct fs
+    withColors d [fc, bc] $ \[fc', bc'] -> do
+      setForeground d gc fc'
+      when (a == 255) (setBackground d gc bc')
+      drawImageString d p gc x y s
+
+printString d p (Utf8 fs) gc fc bc x y _ _ s a =
+    withColors d [fc, bc] $ \[fc', bc'] -> do
+      setForeground d gc fc'
+      when (a == 255) (setBackground d gc bc')
+      liftIO $ wcDrawImageString d p fs gc x y s
+
+#ifdef XFT
+printString dpy drw fs@(Xft fonts) _ fc bc x y ay ht s al =
+  withDrawingColors dpy drw fc bc $ \draw fc' bc' -> do
+    when (al == 255) $ do
+      (a,d)  <- textExtents fs s
+      gi <- xftTxtExtents' dpy fonts s
+      if ay < 0
+        then drawXftRect draw bc' x (y - a) (1 + xglyphinfo_xOff gi) (a + d + 2)
+        else drawXftRect draw bc' x ay (1 + xglyphinfo_xOff gi) ht
+    drawXftString' draw fc' fonts (toInteger x) (toInteger y) s
+#endif
+
+-- | An easy way to print the stuff we need to print
+printStrings :: Drawable
+             -> GC
+             -> NE.NonEmpty XFont
+             -> NE.NonEmpty Int
+             -> Position
+             -> Align
+             -> [((Position, Position), Box)]
+             -> [(Widget, TextRenderInfo, Int, Position)] -> X ()
+printStrings _ _ _ _ _ _ _ [] = return ()
+printStrings dr gc fontlist voffs offs a boxes sl@((s,c,i,l):xs) = do
+  r <- ask
+  let conf = config r
+      d = display r
+      alph = alpha conf
+      Rectangle _ _ wid ht = rect r
+      totSLen = foldr (\(_,_,_,len) -> (+) len) 0 sl
+      remWidth = fi wid - fi totSLen
+      fontst = safeIndex fontlist i
+      voff = safeIndex voffs i
+      offset = case a of
+                 C -> (remWidth + offs) `div` 2
+                 R -> remWidth
+                 L -> offs
+      (fc,bc) = colorComponents conf (tColorsString c)
+  valign <- verticalOffset ht s fontst voff conf
+  let (ht',ay) = case (tBgTopOffset c, tBgBottomOffset c) of
+                   (-1,_)  -> (0, -1)
+                   (_,-1)  -> (0, -1)
+                   (ot,ob) -> (fromIntegral ht - ot - ob, ob)
+  case s of
+    (Text t) -> liftIO $ printString d dr fontst gc fc bc offset valign ay ht' t alph
+    (Icon p) -> liftIO $ maybe (return ())
+                           (B.drawBitmap d dr gc fc bc offset valign)
+                           (lookup p (iconS r))
+    (Hspace _) -> liftIO $ return ()
+  let triBoxes = tBoxes c
+      dropBoxes = filter (\(_,b) -> b `notElem` triBoxes) boxes
+      boxes' = map (\((x1,_),b) -> ((x1, offset + l), b))
+                   (filter (\(_,b) -> b `elem` triBoxes) boxes)
+            ++ map ((offset, offset + l),) (triBoxes \\ map snd boxes)
+  if Prelude.null xs
+    then liftIO $ drawBoxes d dr gc (fromIntegral ht) (dropBoxes ++ boxes')
+    else liftIO $ drawBoxes d dr gc (fromIntegral ht) dropBoxes
+  printStrings dr gc fontlist voffs (offs + l) a boxes' xs
+
+drawBoxes :: Display
+          -> Drawable
+          -> GC
+          -> Position
+          -> [((Position, Position), Box)]
+          -> IO ()
+drawBoxes _ _ _ _ [] = return ()
+drawBoxes d dr gc ht (b:bs) = do
+  let (xx, Box bb offset lineWidth fc mgs) = b
+      lw = fromIntegral lineWidth :: Position
+  withColors d [fc] $ \[fc'] -> do
+    setForeground d gc fc'
+    setLineAttributes d gc lineWidth lineSolid capNotLast joinMiter
+    case bb of
+      BBVBoth -> do
+        drawBoxBorder d dr gc BBTop    offset ht xx lw mgs
+        drawBoxBorder d dr gc BBBottom offset ht xx lw mgs
+      BBHBoth -> do
+        drawBoxBorder d dr gc BBLeft   offset ht xx lw mgs
+        drawBoxBorder d dr gc BBRight  offset ht xx lw mgs
+      BBFull  -> do
+        drawBoxBorder d dr gc BBTop    offset ht xx lw mgs
+        drawBoxBorder d dr gc BBBottom offset ht xx lw mgs
+        drawBoxBorder d dr gc BBLeft   offset ht xx lw mgs
+        drawBoxBorder d dr gc BBRight  offset ht xx lw mgs
+      _ -> drawBoxBorder d dr gc bb    offset ht xx lw mgs
+  drawBoxes d dr gc ht bs
+
+drawBoxBorder :: Display
+              -> Drawable
+              -> GC
+              -> BoxBorder
+              -> BoxOffset
+              -> Position
+              -> (Position, Position)
+              -> Position
+              -> BoxMargins
+              -> IO ()
+drawBoxBorder
+  d dr gc pos (BoxOffset alg offset) ht (x1,x2) lw (BoxMargins mt mr mb ml) = do
+  let (p1,p2) = case alg of
+                 L -> (0,      -offset)
+                 C -> (offset, -offset)
+                 R -> (offset, 0      )
+      lc = lw `div` 2
+  case pos of
+    BBTop    -> drawLine d dr gc (x1 + p1) (mt + lc) (x2 + p2) (mt + lc)
+    BBBottom -> do
+      let lc' = max lc 1 + mb
+      drawLine d dr gc (x1 + p1) (ht - lc') (x2 + p2) (ht - lc')
+    BBLeft   -> drawLine d dr gc (x1 - 1 + ml) p1 (x1 - 1 + ml) (ht + p2)
+    BBRight  -> drawLine d dr gc (x2 + lc - 1 - mr) p1 (x2 + lc - 1 - mr) (ht + p2)
+    _ -> error "unreachable code"