From 2f03b015f18c572759928af68fd5fea3d582a34d Mon Sep 17 00:00:00 2001
From: Kevin Hamacher <kevin.hamacher@ruhr-uni-bochum.de>
Date: Sun, 16 Feb 2020 20:53:25 +0100
Subject: [PATCH] Small performance improvements

---
 src/display.rs      |  3 ---
 src/sound/mod.rs    | 37 +++++++++++++++++++------------------
 src/sound/square.rs |  8 ++++----
 src/sound/wave.rs   |  1 -
 4 files changed, 23 insertions(+), 26 deletions(-)

diff --git a/src/display.rs b/src/display.rs
index 173d4fb..92a9876 100644
--- a/src/display.rs
+++ b/src/display.rs
@@ -459,9 +459,6 @@ impl Display {
 
                     // We need to draw this.
                     let wide_mode = self.control & CTRL_BG_SPRITE_SIZE > 0;
-                    if wide_mode {
-                        // panic!("TODO");
-                    }
                     let limit = match wide_mode {
                         true => 16,
                         false => 8,
diff --git a/src/sound/mod.rs b/src/sound/mod.rs
index 4a341a6..ae42434 100644
--- a/src/sound/mod.rs
+++ b/src/sound/mod.rs
@@ -371,27 +371,28 @@ impl SoundManager {
                     let mut counter = 0;
 
                     while !*do_exit.lock().unwrap() {
-                        let (s1, s2) = {
-                            let mut c_obj = obj.lock().unwrap();
+                        for _ in 0..100 {
+                            let (s1, s2) = {
+                                let mut c_obj = obj.lock().unwrap();
 
-                            // Check for 512 Hz timer
-                            if counter >= (OUTPUT_SAMPLE_RATE / 512) {
-                                c_obj.clock();
-                                counter = 0;
-                            } else {
-                                counter += 1;
-                            }
+                                // Check for 512 Hz timer
+                                if counter >= (OUTPUT_SAMPLE_RATE / 512) {
+                                    c_obj.clock();
+                                    counter = 0;
+                                } else {
+                                    counter += 1;
+                                }
 
-                            // Sample clock
-                            c_obj.sample_clock();
+                                // Sample clock
+                                c_obj.sample_clock();
 
-                            // Get sample
-                            c_obj.sample()
-                        };
-                        let samps = [[s1, s2]];
-                        //let samps = [[0f32, 0f32]];
-                        // No sleep needed, it seems like the playback.write is blocking
-                        playback.write(&samps[..]);
+                                // Get sample
+                                c_obj.sample()
+                            };
+                            let samps = [[s1, s2]];
+                            playback.write(&samps[..]);
+                        }
+                        std::thread::sleep(std::time::Duration::from_millis(1));
                     }
                 })
                 .unwrap(),
diff --git a/src/sound/square.rs b/src/sound/square.rs
index 8c4962a..d56684b 100644
--- a/src/sound/square.rs
+++ b/src/sound/square.rs
@@ -59,17 +59,17 @@ impl SquareWaveGenerator {
         //     0: Addition    (frequency increases)
         //     1: Subtraction (frequency decreases)
         //Bit 2-0 - Number of sweep shift (n: 0-7)
-        self.sweep_change_period = (reg >> 4) & 7;
+        self.sweep_change_period = (reg >> 4) & 0b0111;
         self.sweep_dec = reg & (1 << 3) > 0;
-        self.sweep_change = reg & 7;
+        self.sweep_change = reg & 0b111;
         self.sweep_clock = 0;
     }
 
     pub fn sweep_clock(&mut self) {
         // This should be sampled at 128Hz
-        if self.sweep_change_period > 0
+        if self.sweep_change_period > 0  // enabled
             && self.sweep_clock >= self.sweep_change_period
-            && self.sweep_change > 0
+        // sweep time hit
         {
             self.sweep_clock = 0;
             let change = self.frequency / (2f32.powi(self.sweep_change as _));
diff --git a/src/sound/wave.rs b/src/sound/wave.rs
index 7895e48..d75f195 100644
--- a/src/sound/wave.rs
+++ b/src/sound/wave.rs
@@ -41,7 +41,6 @@ impl WaveGenerator {
     fn update_frequency(&mut self) {
         self.frequency = ((2048 - self.gb_reg_freq) * 2) as _;
         self.time = 0f32;
-        println!("Freq = {}", self.frequency);
     }
 
     pub fn set_lower_freq(&mut self, freq: u8) {