phosphor_app/state/
track.rs

1//! Track state — TrackState, TrackElement, Clip, MidiNote.
2
3use phosphor_core::project::{TrackConfig, TrackKind};
4
5// ── Track Element Navigation ──
6
7#[derive(Debug, Clone, Copy, PartialEq, Eq)]
8pub enum TrackElement {
9    Label,
10    Fx,
11    Volume,
12    Mute,
13    Solo,
14    RecordArm,
15    Clip(usize),
16}
17
18impl TrackElement {
19    pub fn move_right(self, num_clips: usize) -> Self {
20        match self {
21            Self::Label => Self::Fx,
22            Self::Fx => Self::Volume,
23            Self::Volume => Self::Mute,
24            Self::Mute => Self::Solo,
25            Self::Solo => Self::RecordArm,
26            Self::RecordArm => {
27                if num_clips > 0 { Self::Clip(0) } else { Self::RecordArm }
28            }
29            Self::Clip(i) => {
30                if i + 1 < num_clips { Self::Clip(i + 1) } else { Self::Clip(i) }
31            }
32        }
33    }
34
35    pub fn move_left(self) -> Self {
36        match self {
37            Self::Label => Self::Label,
38            Self::Fx => Self::Label,
39            Self::Volume => Self::Fx,
40            Self::Mute => Self::Volume,
41            Self::Solo => Self::Mute,
42            Self::RecordArm => Self::Solo,
43            Self::Clip(0) => Self::RecordArm,
44            Self::Clip(i) => Self::Clip(i - 1),
45        }
46    }
47}
48
49// ── Data Models ──
50
51#[derive(Debug, Clone)]
52pub struct Clip {
53    pub number: usize,
54    pub width: u16,
55    pub has_content: bool,
56    /// Start position on the timeline (ticks).
57    pub start_tick: i64,
58    /// Length in ticks.
59    pub length_ticks: i64,
60    /// Notes for piano roll display (from ClipSnapshot).
61    pub notes: Vec<phosphor_core::clip::NoteSnapshot>,
62    /// Notes hidden by shrinking the clip. Stored with start_frac and
63    /// duration_frac as absolute tick ratios (tick / original_length_when_hidden)
64    /// converted to tick offsets for stable restore.
65    /// Format: (tick_offset_from_clip_start, duration_ticks, note, velocity)
66    pub hidden_notes: Vec<(i64, i64, u8, u8)>,
67}
68
69#[derive(Debug, Clone)]
70pub struct TrackState {
71    pub name: String,
72    pub muted: bool,
73    pub soloed: bool,
74    pub armed: bool,
75    pub color_index: usize,
76    pub kind: TrackKind,
77    pub clips: Vec<Clip>,
78    /// Track-level FX chain.
79    pub fx_chain: Vec<super::FxInstance>,
80    /// Fader position as a linear gain, mirroring the audio thread's
81    /// `TrackConfig::volume`. Travel is
82    /// [`TrackConfig::MIN_VOLUME`]..=[`TrackConfig::MAX_VOLUME`]; the audio
83    /// thread's copy is clamped to it by `TrackConfig::set_volume`, so this
84    /// mirror is the only place an out-of-range value could survive.
85    pub volume: f32,
86    /// Unique ID for this track (matches the mixer's track ID).
87    pub mixer_id: Option<usize>,
88    /// Handle to the audio engine's track state. When present, mute/solo/arm/volume
89    /// writes go directly to the audio thread via atomics.
90    pub handle: Option<std::sync::Arc<phosphor_core::project::TrackHandle>>,
91    /// What type of instrument this track has.
92    pub instrument_type: Option<super::InstrumentType>,
93    /// Parameter values (mirrors the audio thread's plugin params).
94    pub synth_params: Vec<f32>,
95}
96
97impl TrackState {
98    /// One press of the fader, in dB.
99    ///
100    /// The fader is stepped in dB rather than in linear gain so that every
101    /// press moves the readout by exactly one. A linear step small enough to
102    /// be useful near the top of the travel is a 6 dB jump near the bottom,
103    /// and three consecutive linear detents around unity all round to the
104    /// same displayed number — a control that does not appear to respond.
105    pub const VOLUME_STEP_DB: f32 = 1.0;
106
107    /// Bottom of the fader's travel, below which it goes to silence.
108    ///
109    /// −40 dB rather than the −60 a drawn fader usually bottoms out at: this
110    /// one is stepped a keypress at a time, and 20 extra presses to reach a
111    /// level that is inaudible anyway is travel nobody wants. Muting a track
112    /// outright is `m`.
113    pub const VOLUME_FLOOR_DB: f32 = -40.0;
114
115    pub fn new(name: &str, color_index: usize, armed: bool, kind: TrackKind, clips: Vec<Clip>) -> Self {
116        Self {
117            name: name.to_string(),
118            muted: false,
119            soloed: false,
120            armed,
121            color_index,
122            kind,
123            clips,
124            fx_chain: Vec::new(),
125            volume: TrackConfig::DEFAULT_VOLUME,
126            mixer_id: None,
127            handle: None,
128            instrument_type: None,
129            synth_params: Vec::new(),
130        }
131    }
132
133    /// Sync mute/solo/arm/volume to the audio thread handle (if wired up).
134    pub fn sync_to_audio(&self) {
135        if let Some(ref h) = self.handle {
136            h.config.muted.store(self.muted, std::sync::atomic::Ordering::Relaxed);
137            h.config.soloed.store(self.soloed, std::sync::atomic::Ordering::Relaxed);
138            h.config.armed.store(self.armed, std::sync::atomic::Ordering::Relaxed);
139            h.config.set_volume(self.volume);
140        }
141    }
142
143    /// The fader position in dB relative to unity. `None` at the bottom of
144    /// the travel, where the answer is negative infinity.
145    pub fn volume_db(&self) -> Option<f32> {
146        (self.volume > 0.0).then(|| 20.0 * self.volume.log10())
147    }
148
149    /// Move the fader by `steps` presses and push the result to the audio
150    /// thread. Returns the new linear gain.
151    ///
152    /// The current position is rounded onto the dB grid before stepping, so
153    /// the fader self-corrects: the default of 0.75 is −2.5 dB, off the grid,
154    /// and the first press lands it on −2 or −3 and every press after that
155    /// moves exactly one. A session saved with a hand-edited volume snaps the
156    /// same way.
157    pub fn adjust_volume(&mut self, steps: i32) -> f32 {
158        let top_db = 20.0 * TrackConfig::MAX_VOLUME.log10();
159        // One step below the floor is the silent position, so stepping down
160        // from the bottom of the travel reaches it and stepping up leaves it.
161        let silent_db = Self::VOLUME_FLOOR_DB - Self::VOLUME_STEP_DB;
162        let current_db = self.volume_db().map_or(silent_db, |db| db.round());
163
164        let target_db =
165            (current_db + steps as f32 * Self::VOLUME_STEP_DB).clamp(silent_db, top_db);
166        self.volume = if target_db < Self::VOLUME_FLOOR_DB {
167            TrackConfig::MIN_VOLUME
168        } else {
169            10.0f32
170                .powf(target_db / 20.0)
171                .clamp(TrackConfig::MIN_VOLUME, TrackConfig::MAX_VOLUME)
172        };
173
174        self.sync_to_audio();
175        self.volume
176    }
177
178    /// Read VU levels from the audio thread handle.
179    pub fn vu_levels(&self) -> (f32, f32) {
180        self.handle.as_ref().map(|h| h.vu.get()).unwrap_or((0.0, 0.0))
181    }
182
183    /// Whether this track is wired to the audio engine.
184    pub fn is_live(&self) -> bool {
185        self.handle.is_some()
186    }
187}
phosphor_app/state/track.rs

phosphor_app/state/
track.rs
