Crate rill_core_model 

Wave Digital Filter (WDF) core and physical modeling — elements, adapters, analysis, and resonant models for analog circuit and acoustic simulation.

All types are generic over rill_core::Transcendental, supporting both f32 and f64. SIMD-accelerated batch processing is available via process_incident_vector methods on Resistor, Capacitor, Inductor, and Diode, plus the free function [elements::process_batch_simd].

Modules

• macros — WDF eDSL macros for defining elements and filters
• analysis — frequency response and distortion analysis
• constants — physical constants and tolerances
• wdf — WDF-based filter models
• string — 1D waveguide string models with stiffness and damping
• plate — 2D FDTD waveguide mesh for plates and membranes
• modal — modal synthesis via parallel resonant filter banks
• cavity — Helmholtz cavity resonators and coupled cavity arrays

Design

WDF elements are built around the WdfElement trait, which defines a port resistance, wave processing, and state update cycle. Elements can be combined via SeriesAdapter and ParallelAdapter to form arbitrary linear circuits. Nonlinear elements like Diode use Newton-Raphson iteration for implicit solution.

References:

• A. Fettweis, “Wave Digital Filters: Theory and Practice” (1986)
• K. J. Werner et al., “An Improved and Generalized Diode Clipper Model for Wave Digital Filters” (2015)

Re-exports

pub use cavity::CavityArray;

pub use cavity::HelmholtzCavity;

pub use modal::ModalModel;

pub use plate::PlateModel;

pub use string::StringModel;

Modules

analysis

Frequency response and distortion analysis

cavity

Helmholtz cavity resonators and coupled cavity arrays Cavity resonator models — Helmholtz single-cavity and coupled cavity arrays.

constants

Physical constants and tolerances Physical constants and numerical tolerances used throughout the crate.

macros

WDF eDSL macros for defining elements and filters

modal

Modal synthesis via parallel resonant filter banks Modal resonator — parallel bank of 2-pole filters.

plate

2D FDTD waveguide mesh for plates and membranes 2D plate/membrane model — waveguide mesh with FDTD.

string

1D waveguide string models with stiffness and damping Physical string model — digital waveguide with stiffness and damping.

tape

Analog tape recording and playback head models

wdf

WDF-based filter models WDF-based filters.

Macros

wdf_cascade

Generate a cascaded WDF filter from identical sections.

wdf_compose

Compose two WDF elements into Series or Parallel.

wdf_element

Generate a single WDF element struct implementing WdfElement.

Structs

Capacitor

Capacitor WDF element (trapezoidal integration)

Diode

Diode WDF element (nonlinear, Newton-Raphson solution)

Inductor

Inductor WDF element (trapezoidal integration)

OpAmp

Operational amplifier model with slew-rate limiting, bandwidth roll-off, and voltage rail clamping.

ParallelAdapter

Parallel adapter — connects WDF elements in parallel

Resistor

Resistor WDF element

SeriesAdapter

Series adapter — connects WDF elements in series

WaveVariables

Wave variables: a (incident), b (reflected)

Traits

Transcendental

Transcendental operations (sin, cos, sqrt, exp, ln).

WdfElement

Base WDF element trait.