module FRP.Helm.Mouse (
Mouse(..),
isDown,
position, x, y
) where
import Data.Bits
import Foreign.Marshal.Alloc
import Foreign.Ptr
import Foreign.Storable
import FRP.Elerea.Simple
import FRP.Helm.Utilities
import qualified Graphics.UI.SDL as SDL
data Mouse
= LeftMouse
| MiddleMouse
| RightMouse
| X1Mouse
| X2Mouse deriving (Show, Eq, Ord, Read)
instance Enum Mouse where
fromEnum LeftMouse = 1
fromEnum MiddleMouse = 2
fromEnum RightMouse = 3
fromEnum X1Mouse = 4
fromEnum X2Mouse = 5
toEnum 1 = LeftMouse
toEnum 2 = MiddleMouse
toEnum 3 = RightMouse
toEnum 4 = X1Mouse
toEnum 5 = X2Mouse
toEnum _ = error "FRP.Helm.Mouse.Mouse.toEnum: bad argument"
position :: SignalGen (Signal (Int, Int))
position = effectful $ alloca $ \xptr -> alloca $ \yptr -> do
_ <- SDL.getMouseState xptr yptr
x_ <- peek xptr
y_ <- peek yptr
return (fromIntegral x_, fromIntegral y_)
x :: SignalGen (Signal Int)
x = fst <~ position
y :: SignalGen (Signal Int)
y = snd <~ position
isDown :: Mouse -> SignalGen (Signal Bool)
isDown m = effectful $ do
flags <- SDL.getMouseState nullPtr nullPtr
return $ (.&.) (fromIntegral flags) (fromEnum m) /= 0