boomslang-0.0.1: src/External/Input/Mouse.hs

module External.Input.Mouse
  ( clicked
  , module External.Input.Mouse.Buttons
  )
  where

-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

import qualified Graphics.UI.GLFW as GLFW

import Game.G (G, liftIO)

import External.Input.Mouse.Buttons

-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

clicked :: GLFW.MouseButton -> G (Maybe (Double,Double))
clicked b = liftIO $ do
    r <- GLFW.mouseButtonIsPressed b
    if r
      then do
          (x, y) <- GLFW.getMousePosition
          (w, h) <- GLFW.getWindowDimensions
          let w2 = fromIntegral w / 2
              h2 = fromIntegral h / 2
              x' = (fromIntegral x - w2) / w2
              y' = (h2 - fromIntegral y) / h2
          return $ Just (x',y')
      else return Nothing