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playdate-kit/Sources/PlaydateKit/SoundEffect.swift
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javier 2e7ee12ec1
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Adjusted the naming of the library in the Package file.
2026-07-25 12:02:55 +02:00

394 lines
15 KiB
Swift

//
// SoundEffect.swift
// SoundEffect wrappers: filters, bitcrusher, ring modulator, delay line,
// and overdrive.
//
internal import CPlaydate
private var effectAPI: UnsafePointer<playdate_sound_effect> { Playdate.effectAPI.unsafelyUnwrapped }
extension Sound {
/// An effect that processes a channel's audio: the base class of the
/// built-in effects. Wraps `SoundEffect`.
public class Effect {
/// Processes up to `AUDIO_FRAMES_PER_CYCLE` sample frames in signed
/// Q8.24 format. `bufferActive` is `false` when the input buffer is
/// silent. Returns `true` if the effect produced output.
public typealias Processor = (_ left: UnsafeMutableBufferPointer<Int32>,
_ right: UnsafeMutableBufferPointer<Int32>?,
_ bufferActive: Bool) -> Bool
let pointer: OpaquePointer
let isOwned: Bool
private var retainedMixModulator: SignalValue?
private var processorBox: Unmanaged<ProcessorBox>?
final class ProcessorBox {
let processor: Processor
init(_ processor: @escaping Processor) { self.processor = processor }
}
init(pointer: OpaquePointer, isOwned: Bool) {
self.pointer = pointer
self.isOwned = isOwned
}
/// Creates an effect that processes audio with a Swift callback.
public init(processor: @escaping Processor) {
let box = Unmanaged.passRetained(ProcessorBox(processor))
processorBox = box
pointer = effectAPI.pointee.newEffect.unsafelyUnwrapped({ effect, left, right, nsamples, bufactive in
guard let effect, let left,
let userdata = effectAPI.pointee.getUserdata.unsafelyUnwrapped(effect) else { return 0 }
let box = Unmanaged<ProcessorBox>.fromOpaque(userdata).takeUnretainedValue()
let leftBuffer = UnsafeMutableBufferPointer(start: left, count: Int(nsamples))
let rightBuffer = right.map { UnsafeMutableBufferPointer(start: $0, count: Int(nsamples)) }
return box.processor(leftBuffer, rightBuffer, bufactive != 0) ? 1 : 0
}, box.toOpaque()).unsafelyUnwrapped
isOwned = true
}
deinit {
if isOwned {
effectAPI.pointee.freeEffect.unsafelyUnwrapped(pointer)
}
processorBox?.release()
}
/// The wet/dry mix: 1 is fully processed, 0 fully dry.
public func setMix(_ level: Float) {
effectAPI.pointee.setMix.unsafelyUnwrapped(pointer, level)
}
public var mixModulator: SignalValue? {
get { SignalValue.wrap(effectAPI.pointee.getMixModulator.unsafelyUnwrapped(pointer)) }
set {
retainedMixModulator = newValue
effectAPI.pointee.setMixModulator.unsafelyUnwrapped(pointer, newValue?.pointer)
}
}
}
// MARK: - Two-pole filter
/// A two-pole IIR filter. Wraps `TwoPoleFilter`.
public final class TwoPoleFilter: Effect {
private static var api: UnsafePointer<playdate_sound_effect_twopolefilter> { Playdate.twoPoleFilterAPI.unsafelyUnwrapped }
public enum Kind: UInt32, Sendable {
case lowPass = 0
case highPass = 1
case bandPass = 2
case notch = 3
case peq = 4
case lowShelf = 5
case highShelf = 6
var cValue: TwoPoleFilterType { TwoPoleFilterType(TwoPoleFilterType.RawValue(rawValue)) }
}
private var retainedFrequencyModulator: SignalValue?
private var retainedResonanceModulator: SignalValue?
public init(kind: Kind = .lowPass) {
super.init(pointer: TwoPoleFilter.api.pointee.newFilter.unsafelyUnwrapped().unsafelyUnwrapped,
isOwned: true)
setKind(kind)
}
deinit {
if isOwned {
TwoPoleFilter.api.pointee.freeFilter.unsafelyUnwrapped(pointer)
}
}
public func setKind(_ kind: Kind) {
TwoPoleFilter.api.pointee.setType.unsafelyUnwrapped(pointer, kind.cValue)
}
/// The center/corner frequency, in Hz.
public func setFrequency(_ frequency: Float) {
TwoPoleFilter.api.pointee.setFrequency.unsafelyUnwrapped(pointer, frequency)
}
public var frequencyModulator: SignalValue? {
get { SignalValue.wrap(TwoPoleFilter.api.pointee.getFrequencyModulator.unsafelyUnwrapped(pointer)) }
set {
retainedFrequencyModulator = newValue
TwoPoleFilter.api.pointee.setFrequencyModulator.unsafelyUnwrapped(pointer, newValue?.pointer)
}
}
/// The gain, used by PEQ and shelf filters.
public func setGain(_ gain: Float) {
TwoPoleFilter.api.pointee.setGain.unsafelyUnwrapped(pointer, gain)
}
public func setResonance(_ resonance: Float) {
TwoPoleFilter.api.pointee.setResonance.unsafelyUnwrapped(pointer, resonance)
}
public var resonanceModulator: SignalValue? {
get { SignalValue.wrap(TwoPoleFilter.api.pointee.getResonanceModulator.unsafelyUnwrapped(pointer)) }
set {
retainedResonanceModulator = newValue
TwoPoleFilter.api.pointee.setResonanceModulator.unsafelyUnwrapped(pointer, newValue?.pointer)
}
}
}
// MARK: - One-pole filter
/// A one-pole low/high-pass filter. Wraps `OnePoleFilter`.
public final class OnePoleFilter: Effect {
private static var api: UnsafePointer<playdate_sound_effect_onepolefilter> { Playdate.onePoleFilterAPI.unsafelyUnwrapped }
private var retainedParameterModulator: SignalValue?
public init() {
super.init(pointer: OnePoleFilter.api.pointee.newFilter.unsafelyUnwrapped().unsafelyUnwrapped,
isOwned: true)
}
deinit {
if isOwned {
OnePoleFilter.api.pointee.freeFilter.unsafelyUnwrapped(pointer)
}
}
/// The filter's cutoff: -1 to 1, where values above 0 are low-pass
/// and values below 0 high-pass.
public func setParameter(_ parameter: Float) {
OnePoleFilter.api.pointee.setParameter.unsafelyUnwrapped(pointer, parameter)
}
public var parameterModulator: SignalValue? {
get { SignalValue.wrap(OnePoleFilter.api.pointee.getParameterModulator.unsafelyUnwrapped(pointer)) }
set {
retainedParameterModulator = newValue
OnePoleFilter.api.pointee.setParameterModulator.unsafelyUnwrapped(pointer, newValue?.pointer)
}
}
}
// MARK: - Bit crusher
/// A bit-crushing and downsampling effect. Wraps `BitCrusher`.
public final class BitCrusher: Effect {
private static var api: UnsafePointer<playdate_sound_effect_bitcrusher> { Playdate.bitCrusherAPI.unsafelyUnwrapped }
private var retainedModulators: [SignalValue] = []
public init() {
super.init(pointer: BitCrusher.api.pointee.newBitCrusher.unsafelyUnwrapped().unsafelyUnwrapped,
isOwned: true)
}
deinit {
if isOwned {
BitCrusher.api.pointee.freeBitCrusher.unsafelyUnwrapped(pointer)
}
}
/// When `true`, `setDepth` values map exponentially to bit depth.
public func setExponential(_ flag: Bool) {
BitCrusher.api.pointee.setExponential.unsafelyUnwrapped(pointer, flag)
}
/// The amount of crushing, 0 (none) to 1 (quantized to 1 bit).
public func setDepth(_ depth: Float) {
BitCrusher.api.pointee.setDepth.unsafelyUnwrapped(pointer, depth)
}
public var depthModulator: SignalValue? {
get { SignalValue.wrap(BitCrusher.api.pointee.getDepthModulator.unsafelyUnwrapped(pointer)) }
set {
retain(newValue)
BitCrusher.api.pointee.setDepthModulator.unsafelyUnwrapped(pointer, newValue?.pointer)
}
}
/// The amount of downsampling, 0 (none) to 1 (every sample repeated).
public func setDownsampling(_ downsampling: Float) {
BitCrusher.api.pointee.setDownsampling.unsafelyUnwrapped(pointer, downsampling)
}
public var downsamplingModulator: SignalValue? {
get { SignalValue.wrap(BitCrusher.api.pointee.getDownsamplingModulator.unsafelyUnwrapped(pointer)) }
set {
retain(newValue)
BitCrusher.api.pointee.setDownsamplingModulator.unsafelyUnwrapped(pointer, newValue?.pointer)
}
}
private func retain(_ modulator: SignalValue?) {
if let modulator { retainedModulators.append(modulator) }
}
}
// MARK: - Ring modulator
/// A ring modulator effect. Wraps `RingModulator`.
public final class RingModulator: Effect {
private static var api: UnsafePointer<playdate_sound_effect_ringmodulator> { Playdate.ringModulatorAPI.unsafelyUnwrapped }
private var retainedFrequencyModulator: SignalValue?
public init() {
super.init(pointer: RingModulator.api.pointee.newRingmod.unsafelyUnwrapped().unsafelyUnwrapped,
isOwned: true)
}
deinit {
if isOwned {
RingModulator.api.pointee.freeRingmod.unsafelyUnwrapped(pointer)
}
}
/// The modulation frequency, in Hz.
public func setFrequency(_ frequency: Float) {
RingModulator.api.pointee.setFrequency.unsafelyUnwrapped(pointer, frequency)
}
public var frequencyModulator: SignalValue? {
get { SignalValue.wrap(RingModulator.api.pointee.getFrequencyModulator.unsafelyUnwrapped(pointer)) }
set {
retainedFrequencyModulator = newValue
RingModulator.api.pointee.setFrequencyModulator.unsafelyUnwrapped(pointer, newValue?.pointer)
}
}
}
// MARK: - Delay line
/// A tap into a delay line; produces audio and can be added to a channel
/// as a source. Wraps `DelayLineTap`.
public final class DelayLineTap: Source {
private static var api: UnsafePointer<playdate_sound_effect_delayline> { Playdate.delayLineAPI.unsafelyUnwrapped }
/// The delay line is retained so the tap stays valid.
private let delayLine: DelayLine
private var retainedDelayModulator: SignalValue?
init(pointer: OpaquePointer, delayLine: DelayLine) {
self.delayLine = delayLine
super.init(pointer: pointer, isOwned: true)
}
deinit {
DelayLineTap.api.pointee.freeTap.unsafelyUnwrapped(pointer)
}
/// The tap's position in the delay line, in frames.
public func setDelay(frames: Int) {
DelayLineTap.api.pointee.setTapDelay.unsafelyUnwrapped(pointer, Int32(frames))
}
public var delayModulator: SignalValue? {
get { SignalValue.wrap(DelayLineTap.api.pointee.getTapDelayModulator.unsafelyUnwrapped(pointer)) }
set {
retainedDelayModulator = newValue
DelayLineTap.api.pointee.setTapDelayModulator.unsafelyUnwrapped(pointer, newValue?.pointer)
}
}
/// For stereo delay lines: swaps the left and right channels.
public func setChannelsFlipped(_ flipped: Bool) {
DelayLineTap.api.pointee.setTapChannelsFlipped.unsafelyUnwrapped(pointer, flipped ? 1 : 0)
}
}
/// A delay line effect. Wraps `DelayLine`.
public final class DelayLine: Effect {
private static var api: UnsafePointer<playdate_sound_effect_delayline> { Playdate.delayLineAPI.unsafelyUnwrapped }
/// Creates a delay line holding `length` frames.
public init(length: Int, stereo: Bool = false) {
super.init(pointer: DelayLine.api.pointee.newDelayLine.unsafelyUnwrapped(
Int32(length), stereo ? 1 : 0).unsafelyUnwrapped, isOwned: true)
}
deinit {
if isOwned {
DelayLine.api.pointee.freeDelayLine.unsafelyUnwrapped(pointer)
}
}
/// Changes the delay length. Cannot be larger than the line's
/// original length.
public func setLength(frames: Int) {
DelayLine.api.pointee.setLength.unsafelyUnwrapped(pointer, Int32(frames))
}
/// The feedback level, 0...1.
public func setFeedback(_ feedback: Float) {
DelayLine.api.pointee.setFeedback.unsafelyUnwrapped(pointer, feedback)
}
/// Adds a tap `delay` frames behind the write head. The tap can be
/// added to a channel as a sound source.
public func addTap(delay: Int) -> DelayLineTap? {
guard let tap = DelayLine.api.pointee.addTap.unsafelyUnwrapped(pointer, Int32(delay)) else {
return nil
}
return DelayLineTap(pointer: tap, delayLine: self)
}
}
// MARK: - Overdrive
/// An overdrive/distortion effect. Wraps `Overdrive`.
public final class Overdrive: Effect {
private static var api: UnsafePointer<playdate_sound_effect_overdrive> { Playdate.overdriveAPI.unsafelyUnwrapped }
private var retainedModulators: [SignalValue] = []
public init() {
super.init(pointer: Overdrive.api.pointee.newOverdrive.unsafelyUnwrapped().unsafelyUnwrapped,
isOwned: true)
}
deinit {
if isOwned {
Overdrive.api.pointee.freeOverdrive.unsafelyUnwrapped(pointer)
}
}
/// The input gain applied before clipping.
public func setGain(_ gain: Float) {
Overdrive.api.pointee.setGain.unsafelyUnwrapped(pointer, gain)
}
/// The level where the amplified input clips.
public func setLimit(_ limit: Float) {
Overdrive.api.pointee.setLimit.unsafelyUnwrapped(pointer, limit)
}
public var limitModulator: SignalValue? {
get { SignalValue.wrap(Overdrive.api.pointee.getLimitModulator.unsafelyUnwrapped(pointer)) }
set {
retain(newValue)
Overdrive.api.pointee.setLimitModulator.unsafelyUnwrapped(pointer, newValue?.pointer)
}
}
/// A DC offset applied to the input, making the clipping asymmetric.
public func setOffset(_ offset: Float) {
Overdrive.api.pointee.setOffset.unsafelyUnwrapped(pointer, offset)
}
public var offsetModulator: SignalValue? {
get { SignalValue.wrap(Overdrive.api.pointee.getOffsetModulator.unsafelyUnwrapped(pointer)) }
set {
retain(newValue)
Overdrive.api.pointee.setOffsetModulator.unsafelyUnwrapped(pointer, newValue?.pointer)
}
}
private func retain(_ modulator: SignalValue?) {
if let modulator { retainedModulators.append(modulator) }
}
}
}