Merge pull request #67 from b-ma/feature/audio-buffer-source-node

compliant AudioBufferSourceNode and AudioBuffer

examples/granular.rs

@@ -0,0 +1,64 @@
+use std::fs::File;
+use std::{thread, time};
+use web_audio_api::buffer::AudioBuffer;
+use web_audio_api::context::{AsBaseAudioContext, AudioContext};
+use web_audio_api::node::AudioNode;
+
+// run in release mode
+// cargo run --release --example granular
+
+fn trigger_grain(
+    audio_context: &AudioContext,
+    audio_buffer: &AudioBuffer,
+    position: f64,
+    duration: f64,
+) {
+    let start_time = audio_context.current_time();
+
+    let env = audio_context.create_gain();
+    env.gain().set_value(0.);
+    env.connect(&audio_context.destination());
+
+    let mut src = audio_context.create_buffer_source();
+    src.set_buffer(audio_buffer);
+    src.connect(&env);
+
+    // ramp
+    env.gain().set_value_at_time(0., start_time);
+    env.gain()
+        .linear_ramp_to_value_at_time(1., start_time + duration / 2.);
+    env.gain()
+        .linear_ramp_to_value_at_time(0., start_time + duration);
+
+    src.start_at_with_offset(start_time, position);
+    src.stop_at(start_time + duration);
+}
+
+fn main() {
+    let audio_context = AudioContext::new(None);
+
+    println!("++ scrub into file forward and backward at 0.5 speed");
+
+    // grab audio buffer
+    let file = File::open("sample.wav").unwrap();
+    let audio_buffer = audio_context.decode_audio_data(file);
+
+    let period = 0.05;
+    let grain_duration = 0.2;
+    let mut position = 0.;
+    let mut incr_position = period / 2.;
+
+    loop {
+        trigger_grain(&audio_context, &audio_buffer, position, grain_duration);
+
+        if position + incr_position > audio_buffer.duration() - (grain_duration * 2.)
+            || position + incr_position < 0.
+        {
+            incr_position *= -1.;
+        }
+
+        position += incr_position;
+
+        thread::sleep(time::Duration::from_millis((period * 1000.) as u64));
+    }
+}

examples/trigger_soundfile.rs

@@ -0,0 +1,171 @@
+use std::fs::File;
+use web_audio_api::context::{AsBaseAudioContext, AudioContext};
+use web_audio_api::node::AudioNode;
+
+fn main() {
+    let context = AudioContext::new(None);
+    // @note - `context.resume` is not needed for now
+
+    // load and decode buffer
+    let file = File::open("sample.wav").unwrap();
+    let audio_buffer = context.decode_audio_data(file);
+
+    // @fixme - if only one node in the graph it is never removed even when returning
+    // false, se we put this dummy node in the graph so that other ones are properly
+    // removed
+    let mut src = context.create_buffer_source();
+    src.set_buffer(&audio_buffer);
+    src.connect(&context.destination());
+
+    {
+        println!("++ play until end");
+        let mut src = context.create_buffer_source();
+        src.set_buffer(&audio_buffer);
+        src.connect(&context.destination());
+        src.start_at(context.current_time());
+    }
+
+    std::thread::sleep(std::time::Duration::from_millis(3500));
+
+    {
+        println!("++ play / stop 1sec");
+        let mut src = context.create_buffer_source();
+        src.set_buffer(&audio_buffer);
+        src.connect(&context.destination());
+        src.start_at(context.current_time());
+        src.stop_at(context.current_time() + 1.);
+    }
+
+    std::thread::sleep(std::time::Duration::from_millis(1500));
+
+    {
+        println!("++ play / stop 1sec with offset");
+        let mut src = context.create_buffer_source();
+        src.set_buffer(&audio_buffer);
+        src.connect(&context.destination());
+        src.start_at_with_offset(context.current_time(), 1.);
+        src.stop_at(context.current_time() + 1.);
+    }
+
+    std::thread::sleep(std::time::Duration::from_millis(1500));
+
+    {
+        println!("++ play 1sec with offset and duration");
+        let mut src = context.create_buffer_source();
+        src.set_buffer(&audio_buffer);
+        src.connect(&context.destination());
+        src.start_at_with_offset_and_duration(context.current_time(), 1., 1.);
+    }
+
+    std::thread::sleep(std::time::Duration::from_millis(1500));
+
+    {
+        println!("++ play backward from offset 1.");
+        let mut src = context.create_buffer_source();
+        src.set_buffer(&audio_buffer);
+        src.connect(&context.destination());
+        src.playback_rate().set_value(-1.);
+        src.start_at_with_offset(context.current_time(), 1.);
+    }
+
+    std::thread::sleep(std::time::Duration::from_millis(1500));
+
+    {
+        println!("++ play backward full buffer");
+        let mut src = context.create_buffer_source();
+        src.set_buffer(&audio_buffer);
+        src.connect(&context.destination());
+        src.playback_rate().set_value(-1.);
+        src.start_at_with_offset(context.current_time(), audio_buffer.duration());
+    }
+
+    std::thread::sleep(std::time::Duration::from_millis(3500));
+
+    {
+        println!("++ simple loop (x2)");
+        let mut src = context.create_buffer_source();
+        src.set_buffer(&audio_buffer);
+        src.connect(&context.destination());
+        src.set_loop(true);
+        src.start_at(context.current_time());
+        src.stop_at(context.current_time() + audio_buffer.duration() * 2.);
+    }
+
+    std::thread::sleep(std::time::Duration::from_millis(7000));
+
+    {
+        println!("++ loop between 1 and 2 starting from 0");
+        let mut src = context.create_buffer_source();
+        src.set_buffer(&audio_buffer);
+        src.connect(&context.destination());
+        src.set_loop(true);
+        src.set_loop_start(1.);
+        src.set_loop_end(2.);
+        src.start_at(context.current_time());
+
+        std::thread::sleep(std::time::Duration::from_millis(4500));
+        src.set_loop(false);
+    }
+
+    std::thread::sleep(std::time::Duration::from_millis(2500));
+
+    {
+        println!("++ loop backward between 1 and 2 starting from end");
+        let mut src = context.create_buffer_source();
+        src.set_buffer(&audio_buffer);
+        src.connect(&context.destination());
+        src.playback_rate().set_value(-1.);
+        src.set_loop(true);
+        src.set_loop_start(1.);
+        src.set_loop_end(2.);
+        src.start_at_with_offset(context.current_time(), audio_buffer.duration());
+
+        std::thread::sleep(std::time::Duration::from_millis(4500));
+        src.set_loop(false);
+    }
+
+    std::thread::sleep(std::time::Duration::from_millis(2500));
+
+    println!("++ end of examples");
+
+    for i in 0..9 {
+        let offset = i as f64 / 2.;
+
+        let gain = if i % 4 == 0 { 1. } else { 0.2 };
+        let env = context.create_gain();
+        env.gain().set_value(gain);
+        env.connect(&context.destination());
+
+        let mut src = context.create_buffer_source();
+        src.set_buffer(&audio_buffer);
+        src.connect(&env);
+        src.start_at(context.current_time() + offset);
+    }
+
+    std::thread::sleep(std::time::Duration::from_millis(8000));
+
+    // some stress test
+    // let num_sources_by_sec = 100; // one source per 10ms
+    // // 100 is ok
+    // // 200 starts to click
+    // // 1000 is really not ok
+    // // ...let's agree 10ms is ok for descent granular synthesis
+
+    // for i in 0..num_sources_by_sec {
+    //   // let offset = i as f64 / 1000.; // 10ms - look ok in --release
+    //   let offset = i as f64 / num_sources_by_sec as f64;
+
+    //   // this starts to look like home :)
+    //   let gain = if i % 4 == 0 { 1. } else { 0.3 };
+    //   let env = context.create_gain();
+    //   env.gain().set_value(gain);
+    //   env.connect(&context.destination());
+
+    //   let mut src = context.create_buffer_source();
+    //   src.set_buffer(&audio_buffer);
+    //   src.connect(&env);
+    //   src.start_at(context.current_time() + offset);
+    // }
+
+    // std::thread::sleep(std::time::Duration::from_secs(8));
+}