firewheel_graph/
processor.rs

1use core::num::NonZeroU32;
2
3use ringbuf::traits::Producer;
4use thunderdome::Arena;
5
6#[cfg(not(feature = "std"))]
7use bevy_platform::prelude::{Box, Vec};
8
9use firewheel_core::{
10    clock::InstantSamples,
11    dsp::{buffer::ChannelBuffer, declick::DeclickValues},
12    event::{NodeEvent, ProcEventsIndex},
13    node::{AudioNodeProcessor, ProcExtra},
14    StreamInfo,
15};
16
17use crate::{
18    backend::{AudioBackend, BackendProcessInfo},
19    context::ProcessorChannel,
20    graph::ScheduleHeapData,
21    processor::event_scheduler::{EventScheduler, NodeEventSchedulerData},
22};
23
24#[cfg(feature = "scheduled_events")]
25use crate::context::ClearScheduledEventsType;
26#[cfg(feature = "scheduled_events")]
27use firewheel_core::node::NodeID;
28#[cfg(feature = "scheduled_events")]
29use smallvec::SmallVec;
30
31#[cfg(feature = "musical_transport")]
32use firewheel_core::clock::{InstantMusical, TransportState};
33
34mod event_scheduler;
35mod handle_messages;
36mod process;
37
38#[cfg(feature = "musical_transport")]
39mod transport;
40#[cfg(feature = "musical_transport")]
41use transport::ProcTransportState;
42
43pub struct FirewheelProcessor<B: AudioBackend> {
44    inner: Option<FirewheelProcessorInner<B>>,
45    drop_tx: ringbuf::HeapProd<FirewheelProcessorInner<B>>,
46}
47
48impl<B: AudioBackend> Drop for FirewheelProcessor<B> {
49    fn drop(&mut self) {
50        let Some(mut inner) = self.inner.take() else {
51            return;
52        };
53
54        inner.stream_stopped();
55
56        // TODO: Remove this feature gate if `bevy_platform` implements this.
57        #[cfg(feature = "std")]
58        if std::thread::panicking() {
59            inner.poisoned = true;
60        }
61
62        let _ = self.drop_tx.try_push(inner);
63    }
64}
65
66impl<B: AudioBackend> FirewheelProcessor<B> {
67    pub(crate) fn new(
68        processor: FirewheelProcessorInner<B>,
69        drop_tx: ringbuf::HeapProd<FirewheelProcessorInner<B>>,
70    ) -> Self {
71        Self {
72            inner: Some(processor),
73            drop_tx,
74        }
75    }
76
77    pub fn process_interleaved(
78        &mut self,
79        input: &[f32],
80        output: &mut [f32],
81        info: BackendProcessInfo<B>,
82    ) {
83        if let Some(inner) = &mut self.inner {
84            inner.process_interleaved(input, output, info);
85        }
86    }
87}
88
89pub(crate) struct FirewheelProcessorInner<B: AudioBackend> {
90    nodes: Arena<NodeEntry>,
91    schedule_data: Option<Box<ScheduleHeapData>>,
92
93    from_graph_rx: ringbuf::HeapCons<ContextToProcessorMsg>,
94    to_graph_tx: ringbuf::HeapProd<ProcessorToContextMsg>,
95
96    event_scheduler: EventScheduler,
97    proc_event_queue: Vec<ProcEventsIndex>,
98
99    sample_rate: NonZeroU32,
100    sample_rate_recip: f64,
101    max_block_frames: usize,
102
103    clock_samples: InstantSamples,
104    shared_clock_input: triple_buffer::Input<SharedClock<B::Instant>>,
105
106    #[cfg(feature = "musical_transport")]
107    proc_transport_state: ProcTransportState,
108
109    hard_clip_outputs: bool,
110
111    pub(crate) extra: ProcExtra,
112
113    /// If a panic occurs while processing, this flag is set to let the
114    /// main thread know that it shouldn't try spawning a new audio stream
115    /// with the shared `Arc<AtomicRefCell<FirewheelProcessorInner>>` object.
116    pub(crate) poisoned: bool,
117    debug_force_clear_buffers: bool,
118}
119
120impl<B: AudioBackend> FirewheelProcessorInner<B> {
121    /// Note, this method gets called on the main thread, not the audio thread.
122    pub(crate) fn new(
123        proc_channel: ProcessorChannel<B>,
124        immediate_event_buffer_capacity: usize,
125        #[cfg(feature = "scheduled_events")] scheduled_event_buffer_capacity: usize,
126        node_event_buffer_capacity: usize,
127        stream_info: &StreamInfo,
128        hard_clip_outputs: bool,
129        buffer_out_of_space_mode: BufferOutOfSpaceMode,
130        debug_force_clear_buffers: bool,
131    ) -> Self {
132        let ProcessorChannel {
133            from_context_rx,
134            to_context_tx,
135            shared_clock_input,
136            logger,
137            store,
138        } = proc_channel;
139        Self {
140            nodes: Arena::new(),
141            schedule_data: None,
142            from_graph_rx: from_context_rx,
143            to_graph_tx: to_context_tx,
144            event_scheduler: EventScheduler::new(
145                immediate_event_buffer_capacity,
146                #[cfg(feature = "scheduled_events")]
147                scheduled_event_buffer_capacity,
148                buffer_out_of_space_mode,
149            ),
150            proc_event_queue: Vec::with_capacity(node_event_buffer_capacity),
151            sample_rate: stream_info.sample_rate,
152            sample_rate_recip: stream_info.sample_rate_recip,
153            max_block_frames: stream_info.max_block_frames.get() as usize,
154            clock_samples: InstantSamples(0),
155            shared_clock_input,
156            #[cfg(feature = "musical_transport")]
157            proc_transport_state: ProcTransportState::new(),
158            hard_clip_outputs,
159            extra: ProcExtra {
160                scratch_buffers: ChannelBuffer::new(stream_info.max_block_frames.get() as usize),
161                declick_values: DeclickValues::new(stream_info.declick_frames),
162                logger,
163                store,
164            },
165            poisoned: false,
166            debug_force_clear_buffers,
167        }
168    }
169}
170
171pub(crate) struct NodeEntry {
172    pub processor: Box<dyn AudioNodeProcessor>,
173    pub prev_output_was_silent: bool,
174
175    event_data: NodeEventSchedulerData,
176}
177
178pub(crate) enum ContextToProcessorMsg {
179    EventGroup(Vec<NodeEvent>),
180    NewSchedule(Box<ScheduleHeapData>),
181    HardClipOutputs(bool),
182    #[cfg(feature = "musical_transport")]
183    SetTransportState(Box<TransportState>),
184    #[cfg(feature = "scheduled_events")]
185    ClearScheduledEvents(SmallVec<[ClearScheduledEventsEvent; 1]>),
186}
187
188pub(crate) enum ProcessorToContextMsg {
189    ReturnEventGroup(Vec<NodeEvent>),
190    ReturnSchedule(Box<ScheduleHeapData>),
191    #[cfg(feature = "musical_transport")]
192    ReturnTransportState(Box<TransportState>),
193    #[cfg(feature = "scheduled_events")]
194    ReturnClearScheduledEvents(SmallVec<[ClearScheduledEventsEvent; 1]>),
195}
196
197#[cfg(feature = "scheduled_events")]
198pub(crate) struct ClearScheduledEventsEvent {
199    /// If `None`, then clear events for all nodes.
200    pub node_id: Option<NodeID>,
201    pub event_type: ClearScheduledEventsType,
202}
203
204#[derive(Clone)]
205pub(crate) struct SharedClock<I: Clone> {
206    pub clock_samples: InstantSamples,
207    #[cfg(feature = "musical_transport")]
208    pub current_playhead: Option<InstantMusical>,
209    #[cfg(feature = "musical_transport")]
210    pub speed_multiplier: f64,
211    #[cfg(feature = "musical_transport")]
212    pub transport_is_playing: bool,
213    pub process_timestamp: Option<I>,
214}
215
216impl<I: Clone> Default for SharedClock<I> {
217    fn default() -> Self {
218        Self {
219            clock_samples: InstantSamples(0),
220            #[cfg(feature = "musical_transport")]
221            current_playhead: None,
222            #[cfg(feature = "musical_transport")]
223            speed_multiplier: 1.0,
224            #[cfg(feature = "musical_transport")]
225            transport_is_playing: false,
226            process_timestamp: None,
227        }
228    }
229}
230
231/// How to handle event buffers on the audio thread running out of space.
232#[derive(Default, Debug, Clone, Copy, PartialEq, PartialOrd)]
233#[cfg_attr(feature = "bevy_reflect", derive(bevy_reflect::Reflect))]
234#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
235pub enum BufferOutOfSpaceMode {
236    #[default]
237    /// If an event buffer on the audio thread ran out of space to fit new
238    /// events, reallocate on the audio thread to fit the new items. If this
239    /// happens, it may cause underruns (audio glitches), and a warning will
240    /// be logged.
241    AllocateOnAudioThread,
242    /// If an event buffer on the audio thread ran out of space to fit new
243    /// events, then panic.
244    Panic,
245    /// If an event buffer on the audio thread ran out of space to fit new
246    /// events, drop those events to avoid allocating on the audio thread.
247    /// If this happens, a warning will be logged.
248    ///
249    /// (Not generally recommended, but the option is here if you want it.)
250    DropEvents,
251}
firewheel_graph/processor.rs

firewheel_graph/
processor.rs
