From ed9c093d0b779e3fcd34f491ca9ceda5280580cd Mon Sep 17 00:00:00 2001
From: Amjad Alsharafi <26300843+Amjad50@users.noreply.github.com>
Date: Thu, 26 Dec 2024 18:49:41 +0800
Subject: [PATCH] Updated APU to return stereo audio

Signed-off-by: Amjad Alsharafi <26300843+Amjad50@users.noreply.github.com>
---
 plastic_core/src/apu2a03/channel.rs | 1 +
 plastic_core/src/apu2a03/mod.rs     | 3 ++-
 plastic_core/src/misc.rs            | 4 +---
 plastic_core/src/nes.rs             | 2 +-
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/plastic_core/src/apu2a03/channel.rs b/plastic_core/src/apu2a03/channel.rs
index a40a59e..3ee52bb 100644
--- a/plastic_core/src/apu2a03/channel.rs
+++ b/plastic_core/src/apu2a03/channel.rs
@@ -26,6 +26,7 @@ impl BufferedChannel {
 
     pub fn recored_sample(&mut self, sample: f32) {
         self.buffer.push_back(sample);
+        self.buffer.push_back(sample);
     }
 
     pub fn take_buffer(&mut self) -> Vec<f32> {
diff --git a/plastic_core/src/apu2a03/mod.rs b/plastic_core/src/apu2a03/mod.rs
index 699784a..8ab48bc 100644
--- a/plastic_core/src/apu2a03/mod.rs
+++ b/plastic_core/src/apu2a03/mod.rs
@@ -11,7 +11,7 @@ use crate::common::{
     CPU_FREQ,
 };
 use apu2a03_registers::Register;
-use channel::{APUChannel, BufferedChannel, Dac, TimedAPUChannel};
+use channel::{BufferedChannel, Dac, TimedAPUChannel};
 use channels::{Dmc, NoiseWave, SquarePulse, TriangleWave};
 use envelope::EnvelopedChannel;
 use length_counter::LengthCountedChannel;
@@ -485,6 +485,7 @@ impl APU2A03 {
         }
     }
 
+    /// Take and return the audio buffer as f32 format stereo (2 channels)
     pub fn take_audio_buffer(&mut self) -> Vec<f32> {
         self.buffered_channel.take_buffer()
     }
diff --git a/plastic_core/src/misc.rs b/plastic_core/src/misc.rs
index b283011..4a2b190 100644
--- a/plastic_core/src/misc.rs
+++ b/plastic_core/src/misc.rs
@@ -92,7 +92,7 @@ impl Fps {
 /// `speed_modifier == 1.0` means normal speed
 pub fn process_audio(audio_buffer: &[f32], speed_modifier: f32) -> Vec<f32> {
     let target_len = (audio_buffer.len() as f32 * speed_modifier).ceil() as usize;
-    let mut adjusted_buffer = Vec::with_capacity(target_len * 2);
+    let mut adjusted_buffer = Vec::with_capacity(target_len);
 
     for i in 0..target_len {
         let src_index_f = i as f32 / speed_modifier;
@@ -107,8 +107,6 @@ pub fn process_audio(audio_buffer: &[f32], speed_modifier: f32) -> Vec<f32> {
         } else {
             *audio_buffer.last().unwrap_or(&0.0)
         };
-        // Add the sample twice for left and right channels
-        adjusted_buffer.push(sample);
         adjusted_buffer.push(sample);
     }
 
diff --git a/plastic_core/src/nes.rs b/plastic_core/src/nes.rs
index d9a0422..6b63716 100644
--- a/plastic_core/src/nes.rs
+++ b/plastic_core/src/nes.rs
@@ -353,7 +353,7 @@ impl NES {
         self.cpu.bus().ppu.tv().display_pixel_buffer()
     }
 
-    /// Take and return the audio buffer as f32 format
+    /// Take and return the audio buffer as f32 format stereo (2 channels)
     ///
     /// **Take** here means that if you call the function again, it will return an empty buffer
     /// until the emulator runs again.