Safe Haskell	Safe-Inferred

Midi.Interface

Description

Common interface for the MIDI drivers.

Synopsis

type Initialize a = String -> WantMessage -> (Either Error (RawInterface Midi.WriteMessage) -> IO a) -> IO a
type WantMessage = ByteString.ByteString -> Bool
type ReadChan = TChan.TChan Midi.ReadMessage
data RawInterface write_message = Interface {
- name :: String
- read_channel :: ReadChan
- read_devices :: IO [(Midi.ReadDevice, [Midi.ReadDevice])]
- write_devices :: IO [(Midi.WriteDevice, [Midi.WriteDevice])]
- connect_read_device :: Midi.ReadDevice -> IO Bool
- disconnect_read_device :: Midi.ReadDevice -> IO Bool
- connect_write_device :: Midi.WriteDevice -> IO Bool
- write_message :: write_message -> IO (Maybe Error)
- abort :: IO ()
- now :: IO RealTime
}
type Interface = RawInterface Message
data Message
- = Midi !Midi.WriteMessage
- | AllNotesOff !RealTime
- | AllDevices !RealTime ![Midi.Message]
track_interface :: RawInterface Midi.WriteMessage -> IO Interface
reset_pitch :: RealTime -> Message
reset_controls :: RealTime -> Message
note_tracker :: Bool -> (Midi.WriteMessage -> IO (Maybe err)) -> IO (Message -> IO (Maybe err))

Documentation

type Initialize a Source #

Arguments

= String	register this name with CoreMIDI
-> WantMessage
-> (Either Error (RawInterface Midi.WriteMessage) -> IO a)
-> IO a

type WantMessage = ByteString.ByteString -> Bool Source #

Read msgs that return false are filtered. This uses a raw ByteString to avoid the decode overhead for messages that will be rejected, probably in a high-priority callback. TODO I could probably make this a bitmask or something and put it down in the driver.

type ReadChan = TChan.TChan Midi.ReadMessage Source #

data RawInterface write_message Source #

Produced by an initialize function.

Constructors

Interface

Fields

name :: String
Name of the MIDI driver. Just for debugging.
read_channel :: ReadChan
ReadMessages from the opened ReadDevices become available on this channel.
read_devices :: IO [(Midi.ReadDevice, [Midi.ReadDevice])]
Get currently connected read and write devices, along with a list of aliases for each one.
write_devices :: IO [(Midi.WriteDevice, [Midi.WriteDevice])]
connect_read_device :: Midi.ReadDevice -> IO Bool
Start receiving messages on read_channel from the given device. If it doesn't exist, return False. But it's ok to connect to non-existent ReadDevices because if it does get plugged in, it will be connected automatically.
disconnect_read_device :: Midi.ReadDevice -> IO Bool
Stop receiving messages for this device. False if it wasn't connected.
connect_write_device :: Midi.WriteDevice -> IO Bool
The same as connect_read_device.
write_message :: write_message -> IO (Maybe Error)
Write a message to the output. To avoid overflow, try to not have more than a thousand or so pending. False if the WriteDevice isn't connected.
Messages should be written in increasing time order, with a special case that timestamp 0 messages will be written immediately.
abort :: IO ()
Deschedule all pending write messages.
now :: IO RealTime
Current time according to the MIDI driver.

Instances

Instances details

Show (RawInterface a) Source #
Instance details Defined in Midi.Interface Methods showsPrec :: Int -> RawInterface a -> ShowS # show :: RawInterface a -> String # showList :: [RawInterface a] -> ShowS #

type Interface = RawInterface Message Source #

data Message Source #

Annotate a WriteMessage with additional control messages.

Constructors

Midi !Midi.WriteMessage
AllNotesOff !RealTime	Turn off sounding notes on all devices and channels.
AllDevices !RealTime ![Midi.Message]	Emit the messages for all devices that have been used. This doesn't care if they have sounding notes because control state persists after NoteOff.

Instances

Instances details

Show Message Source #
Instance details Defined in Midi.Interface Methods showsPrec :: Int -> Message -> ShowS # show :: Message -> String # showList :: [Message] -> ShowS #
DeepSeq.NFData Message Source #
Instance details Defined in Midi.Interface Methods rnf :: Message -> () #
Eq Message Source #
Instance details Defined in Midi.Interface Methods (==) :: Message -> Message -> Bool # (/=) :: Message -> Message -> Bool #
Pretty Message Source #
Instance details Defined in Midi.Interface Methods pretty :: Message -> Text Source # format :: Message -> Doc Source # formatList :: [Message] -> Doc Source #

track_interface :: RawInterface Midi.WriteMessage -> IO Interface Source #

reset_pitch :: RealTime -> Message Source #

reset_controls :: RealTime -> Message Source #

note_tracker :: Bool -> (Midi.WriteMessage -> IO (Maybe err)) -> IO (Message -> IO (Maybe err)) Source #

Wrap a write_message and keep track of which notes are on. It can then handle reset messages which need to know current state to reset it.

This is necessary because some synthesizers do not support AllNotesOff, but also relieves callers of having to track which devices and channels have active notes.