emu works again

gb-emu/Cargo.toml

@@ -6,7 +6,7 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-gb-emu-lib = { path = "../lib" }
+gb-emu-lib = { path = "../lib", features = [] }
 clap = {version = "4.1.8", features = ["derive"]}
 minifb = { path = "../vendored/rust_minifb" }
 gilrs = "0.10.1"

gb-emu/src/main.rs

@@ -85,7 +85,7 @@ fn main() {
         cycle_count: args.cycle_count,
     };
 
-    let tile_window: Option<Box<dyn Renderer>> = if args.tile_window {
+    let tile_window: Option<Box<dyn Renderer<u32>>> = if args.tile_window {
         Some(Box::new(WindowRenderer::new(factor, None)))
     } else {
         None
@@ -132,7 +132,7 @@ fn create_audio_output() -> (AudioOutput, Stream) {
 
     let sample_rate = config.sample_rate().0;
 
-    let (output, mut rx) = AudioOutput::new(sample_rate as f32);
+    let (output, mut rx) = AudioOutput::new_unfilled(sample_rate as f32, true);
 
     let stream = device
         .build_output_stream(
@@ -183,7 +183,7 @@ impl WindowRenderer {
     }
 }
 
-impl Renderer for WindowRenderer {
+impl Renderer<u32> for WindowRenderer {
     fn prepare(&mut self, width: usize, height: usize) {
         self.width = width;
         self.height = height;

gb-vst/Cargo.toml

@@ -11,7 +11,7 @@ crate-type = ["cdylib", "rlib"]
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-gb-emu-lib = { path = "../lib" }
+gb-emu-lib = { path = "../lib", features = ["async"] }
 nih_plug = { path = "../vendored/nih-plug", features = ["standalone"] }
 baseview = { path = "../vendored/baseview" }
 pixels = "0.11.0"

gb-vst/src/lib.rs

@@ -107,7 +107,7 @@ impl Plugin for GameboyEmu {
         };
         let (sender, receiver) = channel::<EmulatorMessage>();
 
-        let (output, rx) = AudioOutput::new_unfilled(buffer_config.sample_rate);
+        let (output, rx) = AudioOutput::new_unfilled(buffer_config.sample_rate, false);
 
         let (renderer, frame_receiver) = EmulatorRenderer::new();
 

lib/Cargo.toml

@@ -5,6 +5,10 @@ edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
+[features]
+default = []
+async = []
+
 [dependencies]
 rand = "0.8.5"
 async-ringbuf = "0.1.2"

lib/src/connect/mod.rs

@@ -13,6 +13,7 @@ pub enum RomFile {
     Raw(Vec<u8>),
 }
 
+#[cfg(feature = "async")]
 pub trait Renderer<Format: From<Colour>>: Send {
     fn prepare(&mut self, width: usize, height: usize);
 
@@ -25,26 +26,43 @@ pub trait Renderer<Format: From<Colour>>: Send {
     fn set_rumble(&mut self, _rumbling: bool) {}
 }
 
+#[cfg(not(feature = "async"))]
+pub trait Renderer<Format: From<Colour>> {
+    fn prepare(&mut self, width: usize, height: usize);
+
+    fn display(&mut self, buffer: &[Format]);
+
+    fn set_title(&mut self, _title: String) {}
+
+    fn latest_joypad_state(&mut self) -> JoypadState;
+
+    fn set_rumble(&mut self, _rumbling: bool) {}
+}
+
 pub struct AudioOutput {
     pub sample_rate: f32,
     pub send_rb: AsyncHeapProducer<[f32; 2]>,
+    pub wait_for_output: bool,
 }
 
 impl AudioOutput {
-    pub fn new(sample_rate: f32) -> (Self, AsyncHeapConsumer<[f32; 2]>) {
-        let (mut output, rx) = Self::new_unfilled(sample_rate);
+    pub fn new(sample_rate: f32, wait_for_output: bool) -> (Self, AsyncHeapConsumer<[f32; 2]>) {
+        let (mut output, rx) = Self::new_unfilled(sample_rate, wait_for_output);
 
         executor::block_on(
             output
                 .send_rb
-                .push_iter(vec![[0.; 2]; output.send_rb.len() - 1].into_iter()),
+                .push_iter(vec![[0.; 2]; output.send_rb.free_len() - 1].into_iter()),
         )
         .unwrap();
 
         (output, rx)
     }
 
-    pub fn new_unfilled(sample_rate: f32) -> (Self, AsyncHeapConsumer<[f32; 2]>) {
+    pub fn new_unfilled(
+        sample_rate: f32,
+        wait_for_output: bool,
+    ) -> (Self, AsyncHeapConsumer<[f32; 2]>) {
         let rb_len = sample_rate as usize / (60 * 2);
 
         let rb = AsyncHeapRb::<[f32; 2]>::new(rb_len);
@@ -54,6 +72,7 @@ impl AudioOutput {
             Self {
                 sample_rate,
                 send_rb,
+                wait_for_output,
             },
             rx,
         )

lib/src/processor/instructions/primitives.rs

@@ -145,7 +145,10 @@ impl<ColourFormat: From<Colour> + Clone> Cpu<ColourFormat> {
         self.set_or_clear_flag(Flags::Zero, result == 0x0);
         self.set_or_clear_flag(
             Flags::HalfCarry,
-            first.get_low_nibble() - (second.get_low_nibble() + if with_carry { 1 } else { 0 })
+            first
+                .get_low_nibble()
+                .borrowing_sub(second.get_low_nibble(), with_carry)
+                .0
                 > 0xF,
         );
         result

lib/src/processor/memory/mmio/apu.rs

@@ -122,7 +122,11 @@ impl Apu {
     }
 
     fn push_audio(&mut self) {
-        let length = self.out_buffer.len().min(self.output.send_rb.free_len());
+        let length = if self.output.wait_for_output {
+            self.out_buffer.len()
+        } else {
+            self.out_buffer.len().min(self.output.send_rb.free_len())
+        };
 
         executor::block_on(
             self.output