Package net.paulhertz.pixelaudio.sampler

package net.paulhertz.pixelaudio.sampler

Digital audio sampling synthesis classes for PixelAudio.

PixelAudio's sampler engine follows the chain PASamplerInstrumentPoolMulti -> PASamplerInstrumentPool -> PASamplerInstrument -> PASharedBufferSampler -> PASamplerVoice. Small sketches may use PASamplerInstrument directly, while larger gesture-driven sketches can route playback through one or more instrument pools.

The package provides shared-buffer sample playback, polyphonic sampler instruments, ADSR envelope support, pitch and pan controls, gain staging, and event objects used by gesture-driven sampler workflows. It is built on the Minim library for Processing.

Sampler playback processing chain

1. PASamplerInstrumentPoolMulti manages named sampler pools and routes playback to the active pool or a tagged pool.
2. PASamplerInstrumentPool owns a reusable group of sampler instruments, selects an available instrument for each event, and propagates buffer, gain, pan, pitch, and envelope defaults.
3. PASamplerInstrument applies instrument-level gain, pitch, pan, envelope defaults, and sample-rate correction, then forwards playback requests to the sampler backend.
4. PASharedBufferSampler owns the voice pool for one shared mono buffer, starts voices, mixes active voices into Minim's audio callback, and applies mix normalization and soft clipping.
5. PASamplerVoice reads samples from the source buffer, applies per-voice gain, pan, pitch, envelope state, looping state, and release/finish lifecycle handling.

Sampler synthesis engine

• PASamplerInstrument provides the high-level instrument API for pan, gain, pitch scaling, envelopes, buffer replacement, and sampler backend access.
• PASamplerInstrumentPool manages a collection of sampler instruments for polyphony, reuse, and group gain.
• PASamplerInstrumentPoolMulti manages multiple sampler pools for multi-buffer or multi-sample playback.
• PASharedBufferSampler manages sampler voices, voice pooling, looping defaults, panning, gain, smooth voice stealing, and mix profiles.
• PASamplerVoice renders individual sampler voices with gain, pitch, pan, and optional ADSR envelope.

Interfaces and event data

• PAPlayable defines the minimal playable audio API used by sampler instruments and pools.
• PASampler defines the backend sampler contract, including play, looping, stop, sample-rate, and buffer update methods.
• PASamplerPlayable extends PAPlayable for sample-based playback with buffer position, duration, gain, pitch, pan, and envelope parameters.
• PlaybackInfo stores computed duration and timing information for triggered sampler events.
• PitchPolicy defines pitch behavior for sample playback.
• SamplerBrushEvent stores gesture-derived sampler event data such as location, timing, sample position, gain, pitch, pan, and envelope.

Envelope support

• ADSRParams stores parameters for ADSR envelopes and can create Minim ADSR instances.
• ADSRUtils provides utility methods for fitting envelope times to event durations.
• SimpleADSR provides a sample-by-sample ADSR envelope used by sampler voices.

Related Packages

Package	Description
net.paulhertz.pixelaudio	Core classes for PixelAudio, a Processing library that maps between sound and image data.
net.paulhertz.pixelaudio.curves	Gesture, path, and Bézier curve modeling classes for PixelAudio.
net.paulhertz.pixelaudio.example	Example Processing sketches and demonstrations of PixelAudio library functionality.
net.paulhertz.pixelaudio.granular	Granular synthesis classes for PixelAudio.
net.paulhertz.pixelaudio.io	JSON-based persistence for PixelAudio data structures supported by file i/o classes.
net.paulhertz.pixelaudio.schedule	Sample-accurate event scheduling, gesture-based time management, and audio utility functions.

Class	Description
ADSRParams	Value object for Minim ADSR parameters.
ADSRUtils	Utility functions for ADSRParams.
PAPlayable	Generic interface for anything that can be "played." Provides a minimal playback API plus backward-compatible overloads for sampler instruments and other PAPlayable classes.
PASampler	Backend engine contract for sampler implementations.
PASamplerInstrument	Represents a playable instrument that uses a PASampler instantiated as a PASharedBufferSampler to trigger audio playback from a shared buffer that is (currently) a Minim MultiChannelBuffer.
PASamplerInstrumentPool	Manages a group of PASamplerInstruments sharing the same source buffer and audio output.
PASamplerInstrumentPoolMulti	PASamplerInstrumentPoolMulti Manages multiple PASamplerInstrumentPool instances, each keyed by name.
PASamplerPlayable	Specialized playable interface for sample-based instruments.
PASamplerVoice	PASamplerVoice - a single playback "voice" reading from a shared mono buffer.
PASharedBufferSampler	UGen-based sampler that plays multiple PASamplerVoice instances from a single shared mono buffer (channel 0 of a MultiChannelBuffer) which is an array of floating point samples over (-1.0..1.0).
PASharedBufferSampler.MixProfile	Mix-density normalization profiles for polyphonic sampler output, used to control noise and distortion.
PitchPolicy	PitchPolicy determines how PASamplerInstrument / PASamplerVoice should interpret their pitch parameter in combination with a given PASource.
PlaybackInfo	Holds information about a triggered playback event.
SamplerBrushEvent	Stores values used for SamplerBrush event staging, used in tutorial examples such as TutorialOne_03_Drawing.
SimpleADSR	SimpleADSR - software envelope generator with optional exponential curves.
SimpleADSR.Stage