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|
module GraphicsBrush(
Brush,
mkBrush, withBrush,
createBrush, deleteBrush
-- blackBrush, whiteBrush,
) where
import GraphicsTypes
import GraphicsUtilities( bracket, bracket_ )
import qualified Win32
----------------------------------------------------------------
-- The interface
----------------------------------------------------------------
newtype Brush = MkBrush Win32.HBRUSH
mkBrush :: RGB -> (Brush -> Picture) -> Picture
withBrush :: Brush -> Picture -> Picture
createBrush :: RGB -> IO Brush
deleteBrush :: Brush -> IO ()
----------------------------------------------------------------
-- The implementation
----------------------------------------------------------------
createBrush (RGB r g b) =
Win32.createSolidBrush (Win32.rgb r g b) >>= return . MkBrush
deleteBrush (MkBrush b) =
Win32.deleteBrush b
mkBrush rgb p = \ hdc ->
bracket (createBrush rgb) deleteBrush $ \ brush ->
p brush hdc
withBrush (MkBrush brush) p = \ hdc ->
bracket_ (Win32.selectBrush hdc brush) (Win32.selectBrush hdc) (p hdc)
----------------------------------------------------------------
--
-- -- special cases - these should _never_ be deleted
-- blackBrush :: IO Brush
-- whiteBrush :: IO Brush
--
-- blackBrush = Win32.getStockBrush Win32.bLACK_BRUSH >>= return . MkBrush
-- whiteBrush = Win32.getStockBrush Win32.wHITE_BRUSH >>= return . MkBrush
--
----------------------------------------------------------------
|
