firewheel_graph/
processor.rs

1use core::{num::NonZeroU32, usize};
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    log::RealtimeLogger,
14    node::{AudioNodeProcessor, ProcExtra},
15    StreamInfo,
16};
17
18use crate::{
19    backend::{AudioBackend, BackendProcessInfo},
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    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}
118
119impl<B: AudioBackend> FirewheelProcessorInner<B> {
120    /// Note, this method gets called on the main thread, not the audio thread.
121    pub(crate) fn new(
122        from_graph_rx: ringbuf::HeapCons<ContextToProcessorMsg>,
123        to_graph_tx: ringbuf::HeapProd<ProcessorToContextMsg>,
124        shared_clock_input: triple_buffer::Input<SharedClock<B::Instant>>,
125        immediate_event_buffer_capacity: usize,
126        #[cfg(feature = "scheduled_events")] scheduled_event_buffer_capacity: usize,
127        node_event_buffer_capacity: usize,
128        stream_info: &StreamInfo,
129        hard_clip_outputs: bool,
130        buffer_out_of_space_mode: BufferOutOfSpaceMode,
131        logger: RealtimeLogger,
132    ) -> Self {
133        Self {
134            nodes: Arena::new(),
135            schedule_data: None,
136            from_graph_rx,
137            to_graph_tx,
138            event_scheduler: EventScheduler::new(
139                immediate_event_buffer_capacity,
140                #[cfg(feature = "scheduled_events")]
141                scheduled_event_buffer_capacity,
142                buffer_out_of_space_mode,
143            ),
144            proc_event_queue: Vec::with_capacity(node_event_buffer_capacity),
145            sample_rate: stream_info.sample_rate,
146            sample_rate_recip: stream_info.sample_rate_recip,
147            max_block_frames: stream_info.max_block_frames.get() as usize,
148            clock_samples: InstantSamples(0),
149            shared_clock_input,
150            #[cfg(feature = "musical_transport")]
151            proc_transport_state: ProcTransportState::new(),
152            hard_clip_outputs,
153            extra: ProcExtra {
154                scratch_buffers: ChannelBuffer::new(stream_info.max_block_frames.get() as usize),
155                declick_values: DeclickValues::new(stream_info.declick_frames),
156                logger,
157            },
158            poisoned: false,
159        }
160    }
161}
162
163pub(crate) struct NodeEntry {
164    pub processor: Box<dyn AudioNodeProcessor>,
165
166    event_data: NodeEventSchedulerData,
167}
168
169pub(crate) enum ContextToProcessorMsg {
170    EventGroup(Vec<NodeEvent>),
171    NewSchedule(Box<ScheduleHeapData>),
172    HardClipOutputs(bool),
173    #[cfg(feature = "musical_transport")]
174    SetTransportState(Box<TransportState>),
175    #[cfg(feature = "scheduled_events")]
176    ClearScheduledEvents(SmallVec<[ClearScheduledEventsEvent; 1]>),
177}
178
179pub(crate) enum ProcessorToContextMsg {
180    ReturnEventGroup(Vec<NodeEvent>),
181    ReturnSchedule(Box<ScheduleHeapData>),
182    #[cfg(feature = "musical_transport")]
183    ReturnTransportState(Box<TransportState>),
184    #[cfg(feature = "scheduled_events")]
185    ReturnClearScheduledEvents(SmallVec<[ClearScheduledEventsEvent; 1]>),
186}
187
188#[cfg(feature = "scheduled_events")]
189pub(crate) struct ClearScheduledEventsEvent {
190    /// If `None`, then clear events for all nodes.
191    pub node_id: Option<NodeID>,
192    pub event_type: ClearScheduledEventsType,
193}
194
195#[derive(Clone)]
196pub(crate) struct SharedClock<I: Clone> {
197    pub clock_samples: InstantSamples,
198    #[cfg(feature = "musical_transport")]
199    pub current_playhead: Option<InstantMusical>,
200    #[cfg(feature = "musical_transport")]
201    pub speed_multiplier: f64,
202    #[cfg(feature = "musical_transport")]
203    pub transport_is_playing: bool,
204    pub process_timestamp: Option<I>,
205}
206
207impl<I: Clone> Default for SharedClock<I> {
208    fn default() -> Self {
209        Self {
210            clock_samples: InstantSamples(0),
211            #[cfg(feature = "musical_transport")]
212            current_playhead: None,
213            #[cfg(feature = "musical_transport")]
214            speed_multiplier: 1.0,
215            #[cfg(feature = "musical_transport")]
216            transport_is_playing: false,
217            process_timestamp: None,
218        }
219    }
220}
221
222/// How to handle event buffers on the audio thread running out of space.
223#[derive(Default, Debug, Clone, Copy, PartialEq, PartialOrd)]
224pub enum BufferOutOfSpaceMode {
225    #[default]
226    /// If an event buffer on the audio thread ran out of space to fit new
227    /// events, reallocate on the audio thread to fit the new items. If this
228    /// happens, it may cause underruns (audio glitches), and a warning will
229    /// be logged.
230    AllocateOnAudioThread,
231    /// If an event buffer on the audio thread ran out of space to fit new
232    /// events, then panic.
233    Panic,
234    /// If an event buffer on the audio thread ran out of space to fit new
235    /// events, drop those events to avoid allocating on the audio thread.
236    /// If this happens, a warning will be logged.
237    ///
238    /// (Not generally recommended, but the option is here if you want it.)
239    DropEvents,
240}
firewheel_graph/processor.rs

firewheel_graph/
processor.rs
