23 lines
717 B
Haskell
23 lines
717 B
Haskell
module Graphics.Command where
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import FRP.Yampa (Event, Time)
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-- | A datatype representing all possible commands the user
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-- can give through UI.
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data Command
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= -- | A command to resize the window to the given dimensions.
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Resize (Int, Int)
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| -- | A command to change the tick speed of the simulation,
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-- given by a function on the period between ticks.
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ChangeSpeed (Time -> Time)
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getResize :: Command -> Maybe (Int, Int)
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getResize (Resize size) = Just size
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getResize _ = Nothing
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getChangeSpeed :: Command -> Maybe (Time -> Time)
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getChangeSpeed (ChangeSpeed f) = Just f
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getChangeSpeed _ = Nothing
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-- | An event signalling that a command has been given by the user.
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type CommandEvent = Event Command |