From e80b961eca8a1ded25b2c774a2089284029ecb09 Mon Sep 17 00:00:00 2001
From: Alex Janka <alex@alexjanka.com>
Date: Tue, 7 Mar 2023 09:53:56 +1100
Subject: [PATCH] vst makes audio!!

---
 gb-vst/src/lib.rs                    | 22 ++++----------------
 lib/src/lib.rs                       |  5 +----
 lib/src/processor/memory/mmio/apu.rs | 31 +++++++++++++++++++++-------
 3 files changed, 29 insertions(+), 29 deletions(-)

diff --git a/gb-vst/src/lib.rs b/gb-vst/src/lib.rs
index 3ed8cda..d64f412 100644
--- a/gb-vst/src/lib.rs
+++ b/gb-vst/src/lib.rs
@@ -70,34 +70,20 @@ impl Plugin for GameboyEmu {
         _: &mut AuxiliaryBuffers,
         _: &mut impl ProcessContext<Self>,
     ) -> ProcessStatus {
-        nih_log!("processing");
         if let Some(ref mut vars) = self.vars {
-            vars.emulator_core.run_until_buffer_full();
             if buffer.channels() != 2 {
                 panic!()
             }
-            let mut got_any = false;
-            let mut got_nonzero = false;
             for sample in buffer.iter_samples() {
+                if vars.rx.is_empty() {
+                    vars.emulator_core.run_until_buffer_full();
+                }
                 if let Some(a) = executor::block_on(vars.rx.pop()) {
-                    got_any = true;
-                    if (a[0] != 0.) || (a[1] != 0.) {
-                        got_nonzero = true;
-                    }
                     for (source, dest) in a.iter().zip(sample) {
                         *dest = *source;
                     }
                 }
             }
-            if got_any {
-                if got_nonzero {
-                    nih_log!("got some real data");
-                } else {
-                    nih_log!("got some 0's");
-                }
-            }
-        } else {
-            nih_log!("vars not initialised");
         }
         ProcessStatus::KeepAlive
     }
@@ -118,7 +104,7 @@ impl Plugin for GameboyEmu {
             no_save: true,
             bootrom_path: None,
             connect_serial: false,
-            verbose: true,
+            verbose: false,
             cycle_count: false,
         };
         let (sender, receiver) = channel::<EmulatorMessage>();
diff --git a/lib/src/lib.rs b/lib/src/lib.rs
index 580f739..743d5fe 100644
--- a/lib/src/lib.rs
+++ b/lib/src/lib.rs
@@ -154,11 +154,8 @@ impl EmulatorCore {
     }
 
     pub fn run_until_buffer_full(&mut self) {
-        println!("running until buffer full!!");
         while !self.cpu.memory.is_audio_buffer_full() {
-            loop {
-                self.run();
-            }
+            self.run();
         }
     }
 
diff --git a/lib/src/processor/memory/mmio/apu.rs b/lib/src/processor/memory/mmio/apu.rs
index a089c95..83a8b86 100644
--- a/lib/src/processor/memory/mmio/apu.rs
+++ b/lib/src/processor/memory/mmio/apu.rs
@@ -42,6 +42,7 @@ pub struct Apu {
     mixer: Mixer,
     div_apu: u8,
     buffer: Vec<DacSample>,
+    out_buffer: Vec<[f32; 2]>,
     converter: Downsampler,
     output: AudioOutput,
 }
@@ -57,6 +58,7 @@ impl Apu {
             mixer: Mixer::default(),
             div_apu: 0,
             buffer: vec![],
+            out_buffer: vec![],
             converter: Downsampler::new(output.sample_rate),
             output,
         }
@@ -101,18 +103,33 @@ impl Apu {
         );
         if self.buffer.len() >= CYCLES_PER_FRAME {
             self.next_audio();
+        } else if !self.out_buffer.is_empty() {
+            self.push_audio();
         }
     }
 
     fn next_audio(&mut self) {
-        let converted = self.converter.process(
-            self.buffer
-                .drain(..)
-                .map(|v| v.mixed(&self.mixer))
-                .collect::<Vec<[f32; 2]>>(),
+        self.out_buffer.append(
+            &mut self.converter.process(
+                self.buffer
+                    .drain(..)
+                    .map(|v| v.mixed(&self.mixer))
+                    .collect::<Vec<[f32; 2]>>(),
+            ),
         );
-        println!("pushing {} samples to queue", converted.len());
-        executor::block_on(self.output.send_rb.push_slice(&converted)).unwrap();
+
+        self.push_audio();
+    }
+
+    fn push_audio(&mut self) {
+        let length = self.out_buffer.len().min(self.output.send_rb.free_len());
+
+        executor::block_on(
+            self.output
+                .send_rb
+                .push_slice(&self.out_buffer.drain(..length).collect::<Vec<[f32; 2]>>()),
+        )
+        .unwrap();
     }
 
     pub fn is_buffer_full(&self) -> bool {