Hooked up printing FFT result to screen

It's wrong, but it's showing it on the GUI. I'm calling it a win.

2 files changed, 64 insertions, 29 deletions

diff --git a/src/gui.rs b/src/gui.rs
index 42e062d..2b79f06 100644
--- a/src/gui.rs
+++ b/src/gui.rs
@@ -3,7 +3,6 @@ use gtk::prelude::*;
 use std::cell::RefCell;
 use portaudio as pa;
 use std::rc::Rc;
-use std::sync::Arc;
 use std::io;
 use std::io::Write;
 use std::thread;
@@ -14,7 +13,16 @@ const GUI_XML: &'static str = r#"
   <object class="GtkWindow" id="window">
     <property name="title">Rusty Microphone</property>
     <child>
-      <object class="GtkComboBoxText" id="dropdown">
+      <object class="GtkVBox">
+        <child>
+          <object class="GtkComboBoxText" id="dropdown">
+          </object>
+        </child>
+        <child>
+          <object class="GtkLabel" id="pitch-label">
+            <property name="label">Hello world</property>
+          </object>
+        </child>
       </object>
     </child>
   </object>
@@ -40,36 +48,27 @@ pub fn start_gui() -> Result<(), String> {
 
     let gtk_builder = try!(create_window(microphones));
 
-    {
-        let state_for_dropdown = state.clone();
+    connect_dropdown_choose_microphone(&gtk_builder, mic_sender, state.clone());
+
+    let (pitch_sender, pitch_receiver) = channel();
+    
+    start_processing_audio(mic_receiver, pitch_sender);
         
-        let dropdown: gtk::ComboBoxText = try!(
-            gtk_builder.get_object("dropdown").ok_or("GUI does not contain an object with id 'dropdown'")
-        );
-        dropdown.connect_changed(move |dropdown: &gtk::ComboBoxText| {
-            match state_for_dropdown.borrow_mut().pa_stream {
-                Some(ref mut stream) => {stream.stop().ok();},
-                _ => {}
+    let pitch_label: gtk::Label = gtk_builder.get_object("pitch-label").expect("GUI does not contain an object with id 'pitch-label'");
+    gtk::timeout_add(100, move || {
+        let mut pitch = None;
+        loop {
+            let next = pitch_receiver.try_recv().ok();
+            if next.is_none() {
+                break;
             }
-            let selected_mic = dropdown.get_active_id().and_then(|id| id.parse().ok()).expect("Dropdown did not change to a valid value");
-            let stream = ::audio::start_listening(&state_for_dropdown.borrow().pa, selected_mic, mic_sender.clone()).ok();
-            if stream.is_none() {
-                writeln!(io::stderr(), "Failed to open audio channel").ok();
-            }
-            state_for_dropdown.borrow_mut().pa_stream = stream;
-        });
-    }
-
-    let async_thread = thread::spawn(move || {
-        for samples in mic_receiver {
-            let frequency_domain = ::transforms::fft(samples, 44100.0);
-            
-            let max_frequency = frequency_domain.iter()
-                .fold(None as Option<::transforms::FrequencyBucket>, |max, next|
-                      if max.is_none() || max.clone().unwrap().intensity < next.intensity { Some(next.clone()) } else { max }
-                ).unwrap().max_freq;
-            println!("{}Hz", max_frequency.floor());
+            pitch = next;
         }
+        match pitch {
+            Some(pitch) => {pitch_label.set_label(pitch.as_ref());},
+            None => {}
+        };
+        gtk::Continue(true)
     });
 
     gtk::main();
@@ -103,3 +102,34 @@ fn set_dropdown_items(dropdown: &gtk::ComboBoxText, microphones: Vec<(u32, Strin
         dropdown.append(Some(format!("{}", index).as_ref()), name.as_ref());
     }
 }
+
+fn connect_dropdown_choose_microphone(gtk_builder: &gtk::Builder, mic_sender: Sender<Vec<f64>>, state: Rc<RefCell<ApplicationState>>) {
+    let dropdown: gtk::ComboBoxText = gtk_builder.get_object("dropdown").expect("GUI does not contain an object with id 'dropdown'");
+    dropdown.connect_changed(move |dropdown: &gtk::ComboBoxText| {
+        match state.borrow_mut().pa_stream {
+            Some(ref mut stream) => {stream.stop().ok();},
+            _ => {}
+        }
+        let selected_mic = dropdown.get_active_id().and_then(|id| id.parse().ok()).expect("Dropdown did not change to a valid value");
+        let stream = ::audio::start_listening(&state.borrow().pa, selected_mic, mic_sender.clone()).ok();
+        if stream.is_none() {
+            writeln!(io::stderr(), "Failed to open audio channel").ok();
+        }
+        state.borrow_mut().pa_stream = stream;
+    });
+}
+
+fn start_processing_audio(mic_receiver: Receiver<Vec<f64>>, pitch_sender: Sender<String>) {
+    thread::spawn(move || {
+        for samples in mic_receiver {
+            let frequency_domain = ::transforms::fft(samples, 44100.0);
+            
+            let max_frequency = frequency_domain.iter()
+                .fold(None as Option<::transforms::FrequencyBucket>, |max, next|
+                      if max.is_none() || max.clone().unwrap().intensity < next.intensity { Some(next.clone()) } else { max }
+                ).unwrap().max_freq;
+            let pitch = ::transforms::hz_to_pitch(max_frequency);
+            pitch_sender.send(pitch).ok();
+        }
+    });
+}
diff --git a/src/transforms.rs b/src/transforms.rs
index 6b491ac..16478df 100644
--- a/src/transforms.rs
+++ b/src/transforms.rs
@@ -51,3 +51,8 @@ fn fft_on_sine_wave() {
     assert!(peak.min_freq <= frequency);
     assert!(peak.max_freq >= frequency);
 }
+
+pub fn hz_to_pitch(hz: f64) -> String {
+    let pitch_number = 49.0 + 12.0 * (hz / 440.0).log2();
+    pitch_number.floor().to_string()
+}