From 22a27e4b61ce1afe796f9e56b3c43afdd01dcc32 Mon Sep 17 00:00:00 2001
From: Keenan Tims <ktims@gotroot.ca>
Date: Sat, 11 Nov 2023 02:31:56 -0800
Subject: [PATCH] Add FFT progress bar

---
 src/analyzer.rs |  3 +++
 src/main.rs     | 33 ++++++++++++++++++++++++++++++---
 2 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/src/analyzer.rs b/src/analyzer.rs
index 3771a21..ff961ef 100644
--- a/src/analyzer.rs
+++ b/src/analyzer.rs
@@ -203,6 +203,9 @@ impl FftAnalyzer {
         let mut lock = self.last_analysis.lock().unwrap();
         *lock = result;
     }
+    fn progress(&self) -> f32 {
+        self.audio_buf.lock().unwrap().read_since_last_update as f32 / self.fft_length as f32
+    }
 }
 
 impl Analyzer for FftAnalyzer {
diff --git a/src/main.rs b/src/main.rs
index 75e4b59..cf01d6b 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -6,6 +6,7 @@ use egui::Color32;
 use egui_plot::{Legend, Line, Plot};
 
 use std::mem::swap;
+use std::sync::atomic::{AtomicUsize, Ordering};
 use std::sync::mpsc::{channel, Receiver, Sender};
 use std::sync::{Arc, Mutex};
 use std::thread::{self, JoinHandle};
@@ -90,6 +91,7 @@ struct MyApp {
     fft_thread: JoinHandle<()>,
     fft_close_channel: Sender<()>,
     fft_length: usize,
+    fft_progress: Arc<AtomicUsize>,
 
     audio_device: cpal::Device,
     audio_config: cpal::StreamConfig,
@@ -118,6 +120,11 @@ impl eframe::App for MyApp {
                 });
             self.sample_rate_box(ui);
             self.fft_length_box(ui);
+
+            ui.separator();
+            ui.with_layout(egui::Layout::bottom_up(egui::Align::Center), |ui| {
+                self.fft_progress(ui)
+            });
         });
         egui::CentralPanel::default().show(ctx, |ui| {
             ui_plot(ui, self.last_result.clone());
@@ -163,6 +170,14 @@ impl MyApp {
             self.set_fft_length(FFT_LENGTHS[self.ui_selections.fft_length]);
         }
     }
+    fn fft_progress(&mut self, ui: &mut egui::Ui) {
+        let percent = self.fft_progress.load(Ordering::Relaxed) as f32 / self.fft_length as f32;
+        let fft_progress = egui::ProgressBar::new(percent);
+        ui.add(fft_progress);
+        if percent >= 1.0 {
+            self.fft_progress.store(0, Ordering::Relaxed);
+        }
+    }
     fn new(cc: &eframe::CreationContext) -> Self {
         let host = cpal::default_host();
         println!("Audio host: {}", host.id().name());
@@ -223,6 +238,7 @@ impl MyApp {
                 })
                 .unwrap(),
             fft_length: FFT_LENGTHS[DEFAULT_FFT_LENGTH],
+            fft_progress: Arc::new(AtomicUsize::new(0)),
             fft_close_channel: fft_close_channel.0,
             ui_selections: MyAppUiSelections {
                 audio_device: device_names
@@ -295,12 +311,15 @@ impl MyApp {
         );
 
         let new_channel = self.sample_channel.clone();
+        let fft_progress_ref = self.fft_progress.clone();
 
         self.audio_stream = Some(
             self.audio_device
                 .build_input_stream(
                     &self.audio_config,
-                    move |data, _| handle_audio_frame(data, new_channel.clone()),
+                    move |data, _| {
+                        handle_audio_frame(data, new_channel.clone(), fft_progress_ref.clone())
+                    },
                     move |err| panic!("{:?}", err),
                     Some(std::time::Duration::from_secs(1)),
                 )
@@ -405,10 +424,18 @@ fn fft_thread_impl(
     }
 }
 
-fn handle_audio_frame(data: &[SampleType], chan: Sender<Vec<SampleType>>) {
+fn handle_audio_frame(
+    data: &[SampleType],
+    chan: Sender<Vec<SampleType>>,
+    fft_progress: Arc<AtomicUsize>,
+) {
     // Copy and send to processor thread
     // FIXME: Fails at fft lengths > 16384. Are we too slow collecting data?
-    chan.send(data.to_vec()).unwrap_or_default()
+    chan.send(data.to_vec()).unwrap_or_default();
+    fft_progress.store(
+        fft_progress.load(Ordering::Relaxed) + data.len(),
+        Ordering::Relaxed,
+    );
 }
 
 fn main() {