rydia-core

rydia-core is a Rust-based DSP library providing small, composable UGens for offline audio experimentation, with Python bindings via PyO3.
The library focuses on explicit state, sample-by-sample processing, and numerically robust building blocks inspired by SuperCollider UGens and classic DSP literature.

rydia-core is designed for experimentation, analysis, and algorithmic sound construction rather than real-time audio I/O or plugin development.

Minimal example

1. Sine oscillator

import rydia

osc = rydia.SinOsc(48000.0)

samples = []
for _ in range(48000):
    samples.append(osc.process(440.0))

This produces one second of a 440 Hz sine wave at 48 kHz.

2. LFO-driven auto pan

import rydia

lfo = rydia.Lfo(48000.0, waveform=0)  # sine LFO
signal = 0.5

for _ in range(10):
    mod, _ = lfo.process(0.25)
    left, right = rydia.pan2(signal, mod)
    print(left, right)

The LFO output is used as a stereo pan modulation signal.

3. Delay line

import rydia

delay = rydia.DelayL(48000.0, 1.0)

for i in range(10):
    y = delay.process(float(i), 0.1)
    print(y)

This applies a fractional delay using linear interpolation.

For more advanced usage and complete examples, see the examples/ directory.

Provided UGens

Oscillators

• SinOsc
  Phase-accumulating sine oscillator.

• WhiteNoise
  Uniform white noise generator in the range [-1, 1].

Low-frequency modulation

• Lfo
  Sine / triangle / saw LFO with an additional quarter-phase output.

Delay-based primitives

• DelayS, DelayN, DelayL
  Sample, nearest-neighbor, and linearly interpolated delays.

• CombS, CombN, CombL
  Feedback comb filters.

• AllpassS, AllpassN, AllpassL
  Allpass filters based on SuperCollider-style formulations.

Filters and utilities

• Biquad
  Transposed Direct Form II biquad executor.
  Accepts already-normalized coefficients (RBJ-compatible).

• LeakDc
  DC-blocking filter (high-pass) useful after rectifiers and nonlinearities.

• RingBufferS, RingBufferN, RingBufferL
  Power-of-two ring buffers for delay-based structures.

• pan2
  Equal-power stereo panner.

Design principles

• Explicit state, no hidden global context
• Sample-by-sample processing
• Deterministic behavior
• Defensive testing against numerical instability
• Rust as the source of truth for DSP logic

Python is treated as a thin orchestration and experimentation layer.

Non-goals

rydia-core intentionally does not provide:

• Real-time audio I/O
• Plugin formats (VST, AU, AAX)
• High-level synthesis graphs, schedulers, or DAW-like workflows
• Automatic filter design helpers or large DSP toolkits

Those concerns are expected to live in higher-level systems.

Project status

• Python >= 3.10
• Rust core with Python bindings
• Offline / non-realtime oriented
• Experimental / research-focused
• API may evolve within 0.1.x

rydia-core favors clarity and composability over completeness or convenience.