WAGS.Interpret

class AudioInterpret audio engine  where

A class with all possible instructions for interpreting audio. The class is paramaterized by two types:

• audio: an audio context, which could be nothing (ie Unit) if there is audio or FFIAudio if there is audio.
• engine: the output of the engine. For real audio, this is Effect Unit, as playing something from a loudspeaker is a side effect that doesn't return anything. For testing, this is the Instruction type, which is an ADT representation of instructions to an audio engine.

Members

• connectXToY :: Int -> Int -> audio -> engine

  Connect pointer x to pointer y. For example, connect a sine wave oscillator to a highpass filter.

• disconnectXFromY :: Int -> Int -> audio -> engine

  Disconnect pointer x from pointer y. For example, disconnect a sine wave oscillator from a gain unit.

• destroyUnit :: Int -> audio -> engine

  Destroy pointer x. For example, drop a sine wave oscillator from an audio graph. Note that this does not invoke garbage collection - it just removes the reference to the node, allowing it to be garbage collected.

• rebaseAllUnits :: Array { from :: Int, to :: Int } -> audio -> engine

  Rebases the pointers to audio units.

• makeAllpass :: Int -> AudioParameter -> AudioParameter -> audio -> engine

  Make an allpass filter.

• makeBandpass :: Int -> AudioParameter -> AudioParameter -> audio -> engine

  Make a bandpass filter.

• makeConstant :: Int -> OnOff -> AudioParameter -> audio -> engine

  Make a constant source, ie a stream of 0s.

• makeConvolver :: Int -> String -> audio -> engine

  Make a convolution unit, aka reverb.

• makeDelay :: Int -> AudioParameter -> audio -> engine

  Make a delay unit.

• makeDynamicsCompressor :: Int -> AudioParameter -> AudioParameter -> AudioParameter -> AudioParameter -> AudioParameter -> audio -> engine

  Make a compressor/expander.

• makeGain :: Int -> AudioParameter -> audio -> engine

  Make a gain unit.

• makeHighpass :: Int -> AudioParameter -> AudioParameter -> audio -> engine

  Make a highpass filter.

• makeHighshelf :: Int -> AudioParameter -> AudioParameter -> audio -> engine

  Make a highshelf filter.

• makeLoopBuf :: Int -> String -> OnOff -> AudioParameter -> Number -> Number -> audio -> engine

  Make a looping audio buffer node.

• makeLowpass :: Int -> AudioParameter -> AudioParameter -> audio -> engine

  Make a lowpass filter.

• makeLowshelf :: Int -> AudioParameter -> AudioParameter -> audio -> engine

  Make a lowshelf filter.

• makeMicrophone :: Int -> audio -> engine

  Make a microphone.

• makeNotch :: Int -> AudioParameter -> AudioParameter -> audio -> engine

  Make a notch filter.

• makePeaking :: Int -> AudioParameter -> AudioParameter -> AudioParameter -> audio -> engine

  Make a peaking filter.

• makePeriodicOsc :: Int -> String -> OnOff -> AudioParameter -> audio -> engine

  Make a periodic oscillator.

• makePlayBuf :: Int -> String -> Number -> OnOff -> AudioParameter -> audio -> engine

  Make an audio buffer node.

• makeRecorder :: Int -> String -> audio -> engine

  Make a recorder.

• makeSawtoothOsc :: Int -> OnOff -> AudioParameter -> audio -> engine

  Make a sawtooth oscillator.

• makeSinOsc :: Int -> OnOff -> AudioParameter -> audio -> engine

  Make a sine-wave oscillator.

• makeSpeaker :: Int -> audio -> engine

  Make a node representing the loudspeaker. For sound to be rendered, it must go to a loudspeaker.

• makeSquareOsc :: Int -> OnOff -> AudioParameter -> audio -> engine

  Make a square-wave oscillator.

• makeStereoPanner :: Int -> AudioParameter -> audio -> engine

  Make a stereo panner

• makeTriangleOsc :: Int -> OnOff -> AudioParameter -> audio -> engine

  Make a triangle-wave oscillator.

• makeWaveShaper :: Int -> String -> Oversample -> audio -> engine

  Make a wave shaper.

• setBuffer :: Int -> String -> audio -> engine

  Sets the buffer to read from in a playBuf or loopBuf

• setPeriodicOsc :: Int -> String -> audio -> engine

  Sets the periodic oscillator to read from in a periodicOsc

• setOn :: Int -> audio -> engine

  Turn on a generator (an oscillator or playback node).

• setOff :: Int -> audio -> engine

  Turn off a generator (an oscillator or playback node).

• setLoopStart :: Int -> Number -> audio -> engine

  Set the start position of a looping audio buffer node.

• setLoopEnd :: Int -> Number -> audio -> engine

  Set the end position of a looping audio buffer node.

• setRatio :: Int -> AudioParameter -> audio -> engine

  Set the ratio of a compressor.

• setOffset :: Int -> AudioParameter -> audio -> engine

  Set the offset of a constant source node.

• setAttack :: Int -> AudioParameter -> audio -> engine

  Set the attack of a compressor.

• setGain :: Int -> AudioParameter -> audio -> engine

  Set the gain of a gain node or filter.

• setQ :: Int -> AudioParameter -> audio -> engine

  Set the q of a biquad filter.

• setPan :: Int -> AudioParameter -> audio -> engine

  Set the pan of a stereo panner.

• setThreshold :: Int -> AudioParameter -> audio -> engine

  Set the threshold of a compressor.

• setRelease :: Int -> AudioParameter -> audio -> engine

  Set the release of a compressor.

• setKnee :: Int -> AudioParameter -> audio -> engine

  Set the knee of a compressor.

• setDelay :: Int -> AudioParameter -> audio -> engine

  Set the delay of a delay node.

• setPlaybackRate :: Int -> AudioParameter -> audio -> engine

  Set the playback rate of an audio node buffer or loop buffer.

• setFrequency :: Int -> AudioParameter -> audio -> engine

  Set the frequency of an oscillator or filter.

Instances

• AudioInterpret Unit Instruction
• AudioInterpret FFIAudio (Effect Unit)

class SafeToFFI a b | a -> b where

Members

• safeToFFI :: a -> b

Instances

• SafeToFFI Int Int
• SafeToFFI Number Number
• SafeToFFI String String
• SafeToFFI Oversample String
• SafeToFFI OnOff Boolean
• SafeToFFI FFIAudio FFIAudio'
• SafeToFFI AudioParameter FFIAudioParameter'

data AudioBuffer

A multi-channel audio buffer.

Instances

• Show AudioBuffer
• Eq AudioBuffer

data AudioContext :: Type

An AudioContext

data BrowserAudioBuffer :: Type

An AudioBuffer.

data BrowserCamera :: Type

The MediaStream object for a camera.

data BrowserFloatArray :: Type

A Float32Array

data BrowserMicrophone :: Type

The MediaStream object for a microphone.

data BrowserPeriodicWave :: Type

A PeriodicWave.

newtype FFIAudio

Constructors

• FFIAudio FFIAudio'

Instances

• AudioInterpret FFIAudio (Effect Unit)
• SafeToFFI FFIAudio FFIAudio'

type FFIAudio' = { buffers :: Object BrowserAudioBuffer, context :: AudioContext, floatArrays :: Object BrowserFloatArray, microphone :: Nullable BrowserMicrophone, periodicWaves :: Object BrowserPeriodicWave, recorders :: Object (MediaRecorder -> Effect Unit), units :: Foreign, writeHead :: Number }

The audio information that goes to the ffi during rendering.

• context - the audio context. To create an AudioContext, use context.
• writeHead - the moment in time in the audio context at which we are writing. The easing algorithm provided to run makes sure that this is always slightly ahead of the actual audio context time. When starting a scene, this should be set to 0.0.
• units - an object in which audio units are cached and retrieved. To create this, use makeUnitCache.
• microphone - the browser microphone or null if we do not have one.
• recorders - an object recorder rendering functions. Because media recorders do not yet exist when a scene starts, we provide rendering functions and then fill in the actual recorders once the rendering starts.
• buffers - an object containing named audio buffers for playback using PlayBuf or LoopBuf. See the atari-speaks example to see how a buffer is used.
• floatArrays - arrays of 32=bit floats used for wave shaping.
• periodicWaves - array of periodic waves used for creating oscillator nodes.

Instances

• SafeToFFI FFIAudio FFIAudio'

type FFIAudioParameter' = { param :: Number, timeOffset :: Number, transition :: String }

An AudioParameter with the transition field stringly-typed for easier rendering in the FFI.

Instances

• SafeToFFI AudioParameter FFIAudioParameter'

data MediaRecorder :: Type

A MediaRecorder.

audioBuffer :: forall bch blen. Pos bch => Pos blen => Int -> Vec bch (Vec blen Number) -> AudioBuffer

Make a multi-channel audio buffer. Each vector into the multi-channel buffer must be the same length.

audioWorkletAddModule :: AudioContext -> String -> Effect (Promise Unit)

For a given audio context, add the audio worklet module at a given URI.

close :: AudioContext -> Effect Unit

Close an audio context.

context :: Effect AudioContext

Make a new audio context.

decodeAudioDataFromBase64EncodedString :: AudioContext -> String -> Effect (Promise BrowserAudioBuffer)

Given an audio context and a base-64-encoded audio file, decode the content of the string to an audio buffer.

decodeAudioDataFromUri :: AudioContext -> String -> Effect (Promise BrowserAudioBuffer)

Given an audio context and a URI, decode the content of the URI to an audio buffer.

defaultFFIAudio :: AudioContext -> Foreign -> FFIAudio'

getAudioClockTime :: AudioContext -> Effect Number

Gets the audio clock time from an audio context.

getMicrophoneAndCamera :: Boolean -> Boolean -> Aff { camera :: Maybe BrowserCamera, microphone :: Maybe BrowserMicrophone }

isTypeSupported :: String -> Effect Boolean

Is this MIME type supported by this browser.

makeAudioBuffer :: AudioContext -> AudioBuffer -> Effect BrowserAudioBuffer

For a given audio context, use an audio buffer to create a browser audio buffer. This is useful when doing DSP in the browser. Note that AudioBuffer is a purescript type whereas BrowserAudioBuffer is an optimized browser-based type. That means that, once you write to BrowserAudioBuffer, it is effectively a blob and its contents cannot be retrieved using the WAGS API.

makeFloatArray :: Array Number -> Effect BrowserFloatArray

Make a float 32 array. Useful when creating a waveshaper node.

makePeriodicWave :: forall len. Pos len => AudioContext -> Vec len Number -> Vec len Number -> Effect BrowserPeriodicWave

Make a browser periodic wave. A PureScript-ified version of the periodic wave constructor from the Web Audio API. Given an audio context, a vector of real parts of complex numbers, and a vector of imaginary parts of complex numbers, build a periodic wave interpretable by the Web Audio API.

makeUnitCache :: Effect Foreign

Create a unit cache. This returns a fresh empty object {} that is used to cache audio units.

mediaRecorderToUrl :: String -> (String -> Effect Unit) -> MediaRecorder -> Effect Unit

For a given MIME type, pass the URL-ified content of a media recorder as a string to a handler.

mediaRecorderToUrl "audio/ogg" setAudioTagUrlToThisContent recorder

renderAudio :: FFIAudio -> Array (FFIAudio -> Effect Unit) -> Effect Unit

Render audio from an array of audio rendering instructions. This is conceptually the same as taking Array Effect Unit -> Effect Unit and doing map fold <<< sequence. The reason this version is used is because it is ~2x more computationally efficient, which is important in order to be able to hit audio deadlines.

stopMediaRecorder :: MediaRecorder -> Effect Unit

Stops a media recorder