X-Git-Url: https://git.stderr.nl/gitweb?a=blobdiff_plain;f=FPPrac.hs;h=14e8c4f872036b122449cf12242e3338936520c5;hb=25a54fccc78a8c85e3196428c677e213c1eab23e;hp=47b3cad30e0c80c06efa2445adeebc50b9ab7e62;hpb=b4799aaeb1d9b38300143aa3e70d3bd36307a781;p=matthijs%2Fprojects%2Ffpprac.git

diff --git a/FPPrac.hs b/FPPrac.hs
index 47b3cad..14e8c4f 100644
--- a/FPPrac.hs
+++ b/FPPrac.hs
@@ -30,13 +30,14 @@ data Rect = Rect
 
 data Point = Point !Int !Int deriving (Show, Eq)
 
-type Color = Gtk.Color
+-- A color, with RGB values from 0 to 1
+data Color = Color Double Double Double deriving (Show, Eq)
 
 -- Create a Color from Red, Green and Blue values. The inputs should be
 -- between 0 and 255 (inclusive).
 rgb :: Int -> Int -> Int -> Color
-rgb r g b = Gtk.Color (conv r) (conv g) (conv b)
-	where conv = fromInteger . toInteger . (*256)
+rgb r g b = Color (conv r) (conv g) (conv b)
+	where conv = (/256) . fromIntegral
 
 -- | Some predefined colours
 red = rgb 0xff 0 0
@@ -99,6 +100,7 @@ testProg = Main
 
 data IState = forall s. IS
 	{ window    :: Gtk.Window
+	, buffer    :: IORef Cairo.Surface
 	, postponed :: IORef [Request]
 	, usrState  :: IORef s
 	, usrProg   :: TinaStep s
@@ -132,11 +134,11 @@ runTina :: TinaProgram -> IO ()
 runTina Main {..} = do
 	usrState  <- newIORef initialState
 	postponed <- newIORef (GfxText (rgb 0 0 0) (pt 50 50) "foo" : GfxClear :initialRequests)
-	let state = IS { window = undefined, usrProg = eventHandler, .. }
+	let state = IS { window = undefined, buffer = undefined, usrProg = eventHandler, .. }
 	runGUI windowWidth windowHeight state
 
 runGUI :: Int -> Int -> IState -> IO ()
-runGUI w h s = do
+runGUI w h (IS { .. }) = do
 	-- Init GTK.
 	Gtk.initGUI
 	
@@ -150,14 +152,40 @@ runGUI w h s = do
 		       , Gtk.windowDefaultHeight := h
 	               ]
 	Gtk.onDestroy window Gtk.mainQuit
-
-	-- Add the window to the state
-	let state = s { window = window }
 	
+	-- Create a buffer to draw on (name the actual buffer buffer', so we
+	-- can use IS { .. } syntax below to pack the state. Using a record update
+	-- wouldn't work, probably because Cairo.Surface contains an existential
+	-- type...
+	-- We put the buffer in an IORef, so we can change it for a new one
+	-- later on (on window resizes).
+	buffer' <- Cairo.createImageSurface Cairo.FormatARGB32 w h
+	buffer <- newIORef buffer'
+
+	-- Register the expose event
+	Gtk.on window Gtk.exposeEvent $ onExpose buffer
+
+	-- Repack state
+	let state = IS { .. }
+	
+	-- Process any initial requests
+	processPostponed state
+
 	-- Show the window and start the Gtk mainloop.
 	Gtk.widgetShowAll window
 	Gtk.mainGUI
+	
 
+-- | Copy the given surface to the exposed window on an expose event.
+onExpose :: IORef Cairo.Surface -> EventM.EventM EventM.EExpose Bool
+onExpose buffer = do
+	current_buffer <- liftIO $ readIORef buffer
+	dw <- EventM.eventWindow
+	-- Copy the buffer to the window
+	liftIO $ Gtk.renderWithDrawable dw $ do
+		Cairo.setSourceSurface current_buffer 0 0
+		Cairo.paint
+	return True -- No clue what this means
 
 {-
 runGUI s IS {..} = do
@@ -208,6 +236,8 @@ transKey _ _ = return ()
 
 -}
 
+-- | Handlers for various requests.
+miscHandler, winHandler, gfxHandler :: IState -> Request -> Maybe (IO ())
 {-
 miscHandler s@IS {..} (FRead  fn     ) = Just $ readFile fn >>= post s . FileContents fn
 miscHandler   IS {..} (FWrite fn cnts) = Just $ writeFile fn cnts
@@ -233,6 +263,13 @@ winHandler s@IS {..} (WinMenu      ms) = Just $ mkMenu >>= \ms' -> sFrame `set`
 -}
 winHandler _        _                = Nothing
 
+gfxHandler s req = case gfxHandler' req of
+	Nothing -> Nothing
+	Just render -> Just $ do
+		buf <- readIORef (buffer s)
+		Cairo.renderWith buf render
+		Gtk.widgetQueueDraw (window s)
+		
 {-
 gfxHandler IS {..} (GfxLines     col ps)    = Just $ polyline buffer ps [penColor := col] >> dirtyPts sPanel ps
 gfxHandler IS {..} (GfxPolygon   col ps)    = Just $ polygon  buffer ps [penColor := col, brushColor := col] >> dirtyPts sPanel ps
@@ -241,10 +278,26 @@ gfxHandler IS {..} (GfxRectangle col rt)    = Just $ drawRect buffer rt [penColo
 gfxHandler IS {..} (GfxEllipse   col rt)    = Just $ ellipse buffer rt [penColor := col, brushKind := BrushTransparent] >> dirtyRect sPanel rt
 gfxHandler IS {..} (GfxDisc      col rt)    = Just $ ellipse buffer rt [penColor := col, brushColor := col] >> dirtyRect sPanel rt
 gfxHandler IS {..} (GfxFont      st  sz)    = Just $ buffer `set` [ fontSize := sz, fontFace := st ]
-gfxHandler IS {..}  GfxClear                = Just $ dcClear buffer >> windowRefresh sPanel False
 gfxHandler IS {..} (GfxPicture   fd  pt)    = Just $ bitmapCreateFromFile fd >>= \bm -> drawBitmap buffer bm pt False [] >> bitmapGetSize bm >>= dirtyRect' sPanel pt
 -}
-gfxHandler _        _                       = Nothing
+-- | Helper function for gfxHanlder
+gfxHandler' :: Request -> Maybe (Cairo.Render ())
+gfxHandler' (GfxText col (Point x y) st) = Just $ do
+	-- Set the source color, move to the requested position and draw the
+	-- text
+	setSourceColor col
+	Cairo.moveTo (fromIntegral x) (fromIntegral y)
+	Cairo.showText st 
+gfxHandler' GfxClear = Just $ do
+	-- Set the source to white and paint the entire surface with it
+	Cairo.setSourceRGB 1 1 1
+	Cairo.paint
+gfxHandler' _ = Nothing
+
+-- | Sets the source to a pattern fill of the given color
+setSourceColor :: Color -> Cairo.Render ()
+setSourceColor (Color r g b) =
+	Cairo.setSourceRGB r g b
 
 {-
 dirtyPts :: Window a -> [Point] -> IO ()