1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
|
{-# LANGUAGE MultiParamTypeClasses, StandaloneDeriving, ExistentialQuantification, FlexibleInstances #-}
module Phi.Widgets.AlphaBox ( AlphaBox
, alphaBox
) where
import Phi.Types
import Phi.Widget
import Control.Monad
import Control.Monad.State.Strict
import Graphics.Rendering.Cairo
data AlphaBox w s c d = (Widget w s c d) => AlphaBox !Double !w
data AlphaBoxCache w s c d = (Widget w s c d) => AlphaBoxCache !c
instance (Eq s, Display d) => Widget (AlphaBox w s c d) s (AlphaBoxCache w s c d) d where
initWidget (AlphaBox _ w) = initWidget w
initCache (AlphaBox _ w) = AlphaBoxCache $ initCache w
minSize (AlphaBox _ w) = minSize w
weight (AlphaBox _ w) = weight w
render (AlphaBox alpha w) s x y width height screen = do
AlphaBoxCache c <- get
(surfaces, c') <- liftIO $ flip runStateT c $ render w s x y width height screen
put $ AlphaBoxCache c'
let surfacesWidths = zipWith (\(updated, SurfaceSlice x surf) x' -> (updated, x, x'-x, surf)) surfaces (map (\(_, SurfaceSlice x _) -> x) (tail surfaces) ++ [width])
forM surfacesWidths $ \(updated, x, surfWidth, surf) -> do
surf' <- liftIO $ createImageSurface FormatARGB32 surfWidth height
renderWith surf' $ do
setOperator OperatorSource
withPatternForSurface surf setSource
paint
setOperator OperatorDestIn
setSourceRGBA 0 0 0 alpha
paint
return (updated, SurfaceSlice x surf')
handleMessage (AlphaBox _ w) = handleMessage w
alphaBox :: (Widget w s c d) => Double -> w -> AlphaBox w s c d
alphaBox = AlphaBox
|
