replace current_span_length in favor of parameters_changed

CHANGELOG.md

@@ -19,6 +19,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Minimal builds without `cpal` audio output are now supported.
   See `README.md` for instructions. (#349)
 - Added `Sample::is_zero()` method for checking zero samples.
+- Added `TakeDuration::with_fadeout` similar to `TakeDuration::fadeout` but returns `Self`
 
 ### Changed
 - Breaking: `OutputStreamBuilder` should now be used to initialize an audio output stream.
@@ -31,6 +32,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Breaking: The term 'frame' was renamed to 'span' in the crate and documentation.
 - Breaking: Sources now use `f32` samples. To convert to and from other types of samples use functions from
   `dasp_sample` crate. For example `DaspSample::from_sample(sample)`. Remove `integer-decoder` feature.
+- Breaking: Sources wrapping an existing source had a public factory method
+  which is now removed. Something like: `source::amplify(unamplified, 1.2)` must now be
+  written as `unamplified.amplify(1.2)`.
+- Breaking: `TakeDuration::set_filter_fadeout()` has been removed. Use `TakeDuration.fadeout(true)`.
+- `SignalGenerator`'s `Function` is now Copy.
 
 
 ### Fixed

Cargo.toml

@@ -24,6 +24,7 @@ tracing = { version = "0.1.40", optional = true }
 
 atomic_float = { version = "1.1.0", optional = true }
 num-rational = "0.4.2"
+append-only-vec = "0.1.7"
 
 [features]
 default = ["playback", "flac", "vorbis", "wav", "mp3"]
@@ -66,6 +67,8 @@ rstest_reuse = "0.6.0"
 approx = "0.5.1"
 dasp_sample = "0.11.0"
 divan = "0.1.14"
+spectrum-analyzer = "1.6.0"
+itertools = "0.14.0"
 
 [[bench]]
 name = "effects"

benches/pipeline.rs

@@ -1,6 +1,7 @@
 use std::time::Duration;
 
 use divan::Bencher;
+use rodio::ChannelCount;
 use rodio::{source::UniformSourceIterator, Source};
 
 mod shared;
@@ -13,7 +14,7 @@ fn main() {
 #[divan::bench]
 fn long(bencher: Bencher) {
     bencher.with_inputs(|| music_wav()).bench_values(|source| {
-        let mut take_dur = source
+        let effects_applied = source
             .high_pass(300)
             .amplify(1.2)
             .speed(0.9)
@@ -25,13 +26,13 @@ fn long(bencher: Bencher) {
             )
             .delay(Duration::from_secs_f32(0.5))
             .fade_in(Duration::from_secs_f32(2.0))
-            .take_duration(Duration::from_secs(10));
-        take_dur.set_filter_fadeout();
-        let effects_applied = take_dur
+            .take_duration(Duration::from_secs(10))
+            .with_fadeout(true)
             .buffered()
             .reverb(Duration::from_secs_f32(0.05), 0.3)
             .skippable();
-        let resampled = UniformSourceIterator::new(effects_applied, 2, 40_000);
+        let resampled =
+            UniformSourceIterator::new(effects_applied, ChannelCount::new(2).unwrap(), 40_000);
         resampled.for_each(divan::black_box_drop)
     })
 }

benches/shared.rs

@@ -6,7 +6,7 @@ use rodio::{ChannelCount, Sample, SampleRate, Source};
 
 pub struct TestSource {
     samples: vec::IntoIter<Sample>,
-    channels: u16,
+    channels: ChannelCount,
     sample_rate: u32,
     total_duration: Duration,
 }
@@ -29,8 +29,8 @@ impl ExactSizeIterator for TestSource {
 
 impl Source for TestSource {
     #[inline]
-    fn current_span_len(&self) -> Option<usize> {
-        None // forever
+    fn parameters_changed(&self) -> bool {
+        false
     }
 
     #[inline]

examples/mix_multiple_sources.rs

@@ -1,11 +1,12 @@
 use rodio::mixer;
 use rodio::source::{SineWave, Source};
 use std::error::Error;
+use std::num::NonZero;
 use std::time::Duration;
 
 fn main() -> Result<(), Box<dyn Error>> {
     // Construct a dynamic controller and mixer, stream_handle, and sink.
-    let (controller, mixer) = mixer::mixer(2, 44_100);
+    let (controller, mixer) = mixer::mixer(NonZero::new(2).unwrap(), 44_100);
     let stream_handle = rodio::OutputStreamBuilder::open_default_stream()?;
     let sink = rodio::Sink::connect_new(&stream_handle.mixer());
 

src/buffer.rs

@@ -30,7 +30,6 @@ impl SamplesBuffer {
     ///
     /// # Panic
     ///
-    /// - Panics if the number of channels is zero.
     /// - Panics if the samples rate is zero.
     /// - Panics if the length of the buffer is larger than approximately 16 billion elements.
     ///   This is because the calculation of the duration would overflow.
@@ -39,13 +38,12 @@ impl SamplesBuffer {
     where
         D: Into<Vec<Sample>>,
     {
-        assert!(channels >= 1);
         assert!(sample_rate >= 1);
 
         let data = data.into();
         let duration_ns = 1_000_000_000u64.checked_mul(data.len() as u64).unwrap()
             / sample_rate as u64
-            / channels as u64;
+            / channels.get() as u64;
         let duration = Duration::new(
             duration_ns / 1_000_000_000,
             (duration_ns % 1_000_000_000) as u32,
@@ -63,8 +61,8 @@ impl SamplesBuffer {
 
 impl Source for SamplesBuffer {
     #[inline]
-    fn current_span_len(&self) -> Option<usize> {
-        None
+    fn parameters_changed(&self) -> bool {
+        false
     }
 
     #[inline]
@@ -89,14 +87,14 @@ impl Source for SamplesBuffer {
         // and due to the constant sample_rate we can jump to the right
         // sample directly.
 
-        let curr_channel = self.pos % self.channels() as usize;
-        let new_pos = pos.as_secs_f32() * self.sample_rate() as f32 * self.channels() as f32;
+        let curr_channel = self.pos % self.channels().get() as usize;
+        let new_pos = pos.as_secs_f32() * self.sample_rate() as f32 * self.channels().get() as f32;
         // saturate pos at the end of the source
         let new_pos = new_pos as usize;
         let new_pos = new_pos.min(self.data.len());
 
         // make sure the next sample is for the right channel
-        let new_pos = new_pos.next_multiple_of(self.channels() as usize);
+        let new_pos = new_pos.next_multiple_of(self.channels().get() as usize);
         let new_pos = new_pos - curr_channel;
 
         self.pos = new_pos;
@@ -123,36 +121,31 @@ impl Iterator for SamplesBuffer {
 #[cfg(test)]
 mod tests {
     use crate::buffer::SamplesBuffer;
+    use crate::math::ch;
     use crate::source::Source;
 
     #[test]
     fn basic() {
-        let _ = SamplesBuffer::new(1, 44100, vec![0.0, 0.0, 0.0, 0.0, 0.0, 0.0]);
-    }
-
-    #[test]
-    #[should_panic]
-    fn panic_if_zero_channels() {
-        SamplesBuffer::new(0, 44100, vec![0.0, 0.0, 0.0, 0.0, 0.0, 0.0]);
+        let _ = SamplesBuffer::new(ch!(1), 44100, vec![0.0, 0.0, 0.0, 0.0, 0.0, 0.0]);
     }
 
     #[test]
     #[should_panic]
     fn panic_if_zero_sample_rate() {
-        SamplesBuffer::new(1, 0, vec![0.0, 0.0, 0.0, 0.0, 0.0, 0.0]);
+        SamplesBuffer::new(ch!(1), 0, vec![0.0, 0.0, 0.0, 0.0, 0.0, 0.0]);
     }
 
     #[test]
     fn duration_basic() {
-        let buf = SamplesBuffer::new(2, 2, vec![0.0, 0.0, 0.0, 0.0, 0.0, 0.0]);
+        let buf = SamplesBuffer::new(ch!(2), 2, vec![0.0, 0.0, 0.0, 0.0, 0.0, 0.0]);
         let dur = buf.total_duration().unwrap();
         assert_eq!(dur.as_secs(), 1);
         assert_eq!(dur.subsec_nanos(), 500_000_000);
     }
 
     #[test]
     fn iteration() {
-        let mut buf = SamplesBuffer::new(1, 44100, vec![1.0, 2.0, 3.0, 4.0, 5.0, 6.0]);
+        let mut buf = SamplesBuffer::new(ch!(1), 44100, vec![1.0, 2.0, 3.0, 4.0, 5.0, 6.0]);
         assert_eq!(buf.next(), Some(1.0));
         assert_eq!(buf.next(), Some(2.0));
         assert_eq!(buf.next(), Some(3.0));
@@ -172,7 +165,7 @@ mod tests {
         #[test]
         fn channel_order_stays_correct() {
             const SAMPLE_RATE: SampleRate = 100;
-            const CHANNELS: ChannelCount = 2;
+            const CHANNELS: ChannelCount = ch!(2);
             let mut buf = SamplesBuffer::new(
                 CHANNELS,
                 SAMPLE_RATE,
@@ -182,7 +175,10 @@ mod tests {
                     .collect::<Vec<_>>(),
             );
             buf.try_seek(Duration::from_secs(5)).unwrap();
-            assert_eq!(buf.next(), Some(5.0 * SAMPLE_RATE as f32 * CHANNELS as f32));
+            assert_eq!(
+                buf.next(),
+                Some(5.0 * SAMPLE_RATE as f32 * CHANNELS.get() as f32)
+            );
 
             assert!(buf.next().is_some_and(|s| s.trunc() as i32 % 2 == 1));
             assert!(buf.next().is_some_and(|s| s.trunc() as i32 % 2 == 0));

src/common.rs

@@ -1,8 +1,10 @@
+use std::num::NonZero;
+
 /// Stream sample rate (a frame rate or samples per second per channel).
 pub type SampleRate = u32;
 
-/// Number of channels in a stream.
-pub type ChannelCount = u16;
+/// Number of channels in a stream. Can never be Zero
+pub type ChannelCount = NonZero<u16>;
 
 /// Represents value of a single sample.
 /// Silence corresponds to the value `0.0`. The expected amplitude range is  -1.0...1.0.