3 files changed, 45 insertions(+), 11 deletions(-)

M lib/Graphics/Rendering/Rect.hs
M lib/Graphics/Rendering/Rect/Backgrounds.hs
M lib/Graphics/Rendering/Rect/CSS/Backgrounds.hs

@@ 37,7 37,7 @@ styleResolveImages atlas self =
     atlasLookup' None = None
     atlasLookup' (Img path) = Img $ atlasLookup path atlas
     atlasLookup' (Linear a b) = Linear a b
-    atlasLookup' (Radial a b) = Radial a b
+    atlasLookup' (Radial a b cc) = Radial a b cc
 
 atlasFromStyles :: MonadIO m =>
         (Text -> IO DynamicImage) -> [RectStyle Text] -> m Atlas

@@ 145,12 145,14 @@ renderBackgrounds = do
                     u $ v2 $ size', u angle, cs 10 $ map fst stops,
                     us $ ls2fs size' $ map snd $ take 10 stops, u $ length stops
                 ] clip0 a b
-            Radial Ellipse stops -> let sz@(w,h) = size $ clip0 a in ellipse [] [
-                    u $ v2 sz, u $ v2 (w/2, h/2), cs 10 $ map fst stops,
+            Radial Ellipse org stops ->
+                let sz@(_,h) = size $ clip0 a in ellipse [] [
+                    u $ v2 sz, u $ v2 $ l2f' org sz, cs 10 $ map fst stops,
                     us $ ls2fs (0,h/2) $ map snd $ take 10 stops, u $ length stops
                 ] clip0 a b
-            Radial Circle stops -> let (w,h) = size $ clip0 a in circle [] [
-                    u $ v2 (w/2, h/2), u (min w h/2), cs 10 $ map fst stops,
+            Radial Circle org stops ->
+                let sz@(w,h) = size $ clip0 a in circle [] [
+                    u $ v2 $ l2f' org sz, u (min w h/2), cs 10 $ map fst stops,
                     us $ ls2fs (0,min w h/2) $ map snd $ take 10 stops,
                     u $ length stops
                 ] clip0 a b


@@ 187,3 189,10 @@ ls2fs (_,h) ls = resolveAutos 0 $ inner True 0 ls
         next | (x:_) <- fs = x
             | otherwise = 1 -- Step 1 should've taken care of this...
         grad = (next - prev)/(n + 1)
+
+l2f :: Length -> Float -> Float
+l2f Auto x = x/2
+l2f (Scale x) y = x*y
+l2f (Absolute x) _ = x
+l2f' :: (Length, Length) -> (Float, Float) -> (Float, Float)
+l2f' (w,h) (x,y) = (l2f w x, l2f h y)

@@ 24,7 24,7 @@ data Backgrounds img = Backgrounds {
 type C = AlphaColour Float
 
 data Pattern img = None | Img img | Linear Float [(C, Length)]
-    | Radial RadialShape [(C, Length)] deriving (Eq, Show, Read)
+    | Radial RadialShape (Length, Length) [(C, Length)] deriving (Eq, Show, Read)
 data RadialShape = Circle | Ellipse deriving (Eq, Show, Read)
 
 -- We need to resolve images before we can compute the actual lengths!


@@ 79,13 79,38 @@ instance PropertyParser (Backgrounds Text) where
                 Just cs@(_:_:_) <- colourStops pp toks = Just $ Linear angle cs
         inner (Function "radial-gradient":toks)
             | Just cs@(_:_:_) <- colourStops pp (Comma:toks) =
-                Just $ Radial Ellipse cs
-            | Just (shp, ts) <- radArgs toks, Just cs@(_:_:_) <- colourStops pp ts
-                = Just $ Radial shp cs
+                Just $ Radial Ellipse center cs
+            | Just (shp, org, ts) <- radArgs toks,
+                Just cs@(_:_:_) <- colourStops pp ts = Just $ Radial shp org cs
           where
-            radArgs (Ident "circle":ts) = Just (Circle, ts)
-            radArgs (Ident "ellipse":ts) = Just (Ellipse, ts)
+            center = (Scale 0.5, Scale 0.5)
+            radArgs ts | (ts', Ident "at":posStops) <- break (== Ident "at") ts,
+                    Just (shape, _, []) <- radArgs ts',
+                    Just (org, stops) <- position posStops =
+                Just (shape, org, stops)
+            radArgs (Ident "circle":ts) = Just (Circle, center, ts)
+            radArgs (Ident "ellipse":ts) = Just (Ellipse, center, ts)
             radArgs _ = Nothing
+            position (x:y:ts) = position' x y ts *> position' y x ts
+            position _ = Nothing
+            position' x y ts = case ((case x of
+                    Ident "left" -> Scale 0
+                    Ident "center" -> Scale 0.5
+                    Ident "right" -> Scale 1
+                    Percentage _ a -> Scale $ p a
+                    Dimension _ a "px" -> Absolute $ f a
+                    _ -> Auto,
+                case y of
+                    Ident "top" -> Scale 0
+                    Ident "center" -> Scale 0.5
+                    Ident "right" -> Scale 1
+                    Percentage _ a -> Scale $ p a
+                    Dimension _ a "px" -> Absolute $ f a
+                    _ -> Auto),
+                ts) of
+                    ((Auto, _), _) -> Nothing
+                    ((_, Auto), _) -> Nothing
+                    ret -> Just ret
         inner _ = Nothing
     longhand _ self "background-size" t | val@(_:_) <- parseCSSList inner t =
         Just self { bgSize = reverse val }