Trait PurePluginLogic 

pub trait PurePluginLogic: 'static {
    type Params: Params;

    // Required methods
    fn process(
        params: &Self::Params,
        buffer: &mut AudioBuffer<'_, f32>,
        events: &EventList,
        context: &mut ProcessContext<'_>,
    ) -> ProcessStatus;
    fn editor(params: Arc<Self::Params>) -> Box<dyn Editor>;

    // Provided methods
    fn supports_in_place() -> bool { ... }
    fn bus_layouts() -> Vec<BusLayout> { ... }
    fn migrate_state(foreign: &ForeignState<'_>) -> Option<MigratedState> { ... }
}

The stateless f32 plugin trait: PluginLogic minus every state-shaped item. For a pure parameter-driven effect - one whose process is a function of params and input only - this removes the type DspState = () / init / _state: &mut () plumbing entirely:

pub struct Gain;

impl PurePluginLogic for Gain {
    type Params = GainParams;
    fn process(params: &GainParams, buffer: &mut AudioBuffer, events: &EventList, ctx: &mut ProcessContext) -> ProcessStatus {
        /* ... */
    }
    fn editor(params: Arc<GainParams>) -> Box<dyn Editor> { /* ... */ }
}

A blanket impl makes every PurePluginLogic a PluginLogic with DspState = (), so truce::plugin! and every shell consume it unchanged - and implementing both traits for one type is correctly rejected as conflicting. When the plugin grows DSP state, switch the impl header to PluginLogic and add the state type and arguments.

Required: Self::process, Self::editor. Optional: Self::bus_layouts, Self::supports_in_place, Self::migrate_state. Anything state-shaped (reset, save_state, latency, tail, …) needs state to act on - implement PluginLogic directly if you need those.

Required Associated Types

type Params: Params

The plugin’s parameter struct (#[derive(Params)]). Shared, immutable during a block - it arrives by reference every call from the shell, which owns the Arc.

Required Methods

fn process( params: &Self::Params, buffer: &mut AudioBuffer<'_, f32>, events: &EventList, context: &mut ProcessContext<'_>, ) -> ProcessStatus

Process one block of audio as a pure function of params and input. Same real-time contract as the stateful leaf’s process, minus the state argument.

fn editor(params: Arc<Self::Params>) -> Box<dyn Editor>

Construct the editor for this plugin. Required. Same contract as the stateful leaf’s editor.

Provided Methods

fn supports_in_place() -> bool

Opt into zero-copy in-place I/O. Same contract as the stateful leaf’s supports_in_place.

fn bus_layouts() -> Vec<BusLayout>

Supported audio bus configurations. Same contract as the stateful leaf’s bus_layouts. Default: the standard audio effect - stereo and mono.

fn migrate_state(foreign: &ForeignState<'_>) -> Option<MigratedState>

Translate foreign state into truce shape. Same contract as the stateful leaf’s migrate_state - a stateless plugin may still inherit params from a previous framework’s blob.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors