cairo: pure xlib/xft drawing code factored out

2 files changed, 257 insertions, 209 deletions

diff --git a/src/Xmobar/X11/Draw.hs b/src/Xmobar/X11/Draw.hs
index aed9420..6890fb1 100644
--- a/src/Xmobar/X11/Draw.hs
+++ b/src/Xmobar/X11/Draw.hs
@@ -1,5 +1,4 @@
 {-# LANGUAGE CPP #-}
-{-# LANGUAGE TupleSections #-}
 
 ------------------------------------------------------------------------------
 -- |
@@ -20,224 +19,39 @@
 
 module Xmobar.X11.Draw (drawInWin) where
 
-import Prelude hiding (lookup)
 import Control.Monad.IO.Class
 import Control.Monad.Reader
-import Control.Arrow ((&&&))
-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 Graphics.X11.Xlib hiding (Segment)
 
-import Xmobar.Config.Types
-import Xmobar.Run.Parsers hiding (parseString)
-import qualified Xmobar.X11.Bitmap as B
+import Xmobar.Run.Parsers (Segment)
 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
+#ifdef CAIRO
+import Xmobar.X11.CairoDraw
+#else
+import Xmobar.X11.XlibDraw
 #endif
 
-fi :: (Integral a, Num b) => a -> b
-fi = fromIntegral
-
 -- | Draws in and updates the window
 drawInWin :: Rectangle -> [[Segment]] -> X ()
-drawInWin wr@(Rectangle _ _ wid ht) ~[left,center,right] = do
+drawInWin (Rectangle _ _ wid ht) segments = do
   r <- ask
-  let (c,d) = (config &&& display) r
-      (w,(fs,vs)) = (window &&& fontListS &&& 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 p,cl,i,_) = return (Hspace p,cl,i,fi p)
-
-  p <- liftIO $ createPixmap d w wid ht
-                         (defaultDepthOfScreen (defaultScreenOfDisplay d))
-#if XFT
-  when (alpha c /= 255) (liftIO $ drawBackground d p (bgColor c) (alpha c) wr)
+  let d = display r
+      w = window r
+      depth = defaultDepthOfScreen (defaultScreenOfDisplay d)
+  p <- liftIO $ createPixmap d w wid ht depth
+  gc <- liftIO $ createGC d w
+  liftIO $ setGraphicsExposures d gc False
+#ifdef CAIRO
+  drawInPixmap p wid ht segments
 #else
-  _ <- return wr
-#endif
-  withColors d [bgColor c, borderColor c] $ \[bgcolor, bdcolor] -> do
-    gc <- liftIO $ createGC  d w
-    liftIO $ setGraphicsExposures d gc False
-#if XFT
-    when (alpha c == 255) $ do
-#else
-    do
-#endif
-      liftIO $ setForeground d gc bgcolor
-      liftIO $ fillRectangle d p gc 0 0 wid ht
-    -- 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
-    -- copy the pixmap with the new string to the window
-    liftIO $ copyArea d p w gc 0 0 wid ht 0 0
-    -- free up everything (we do not want to leak memory!)
-    liftIO $ freeGC d gc
-    liftIO $ freePixmap d p
-    -- resync (discard events, we don't read/process events from this display conn)
-    liftIO $ sync d True
-
-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
+  drawInPixmap gc p wid ht segments
 #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,d) = (config &&& 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"
+  -- copy the pixmap with the new string to the window
+  liftIO $ copyArea d p w gc 0 0 wid ht 0 0
+  -- free up everything (we do not want to leak memory!)
+  liftIO $ freeGC d gc
+  liftIO $ freePixmap d p
+  -- resync (discard events, we don't read/process events from this display conn)
+  liftIO $ sync d True
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"