chore: reduce size of public interface

src/apu.rs

@@ -437,7 +437,7 @@ impl Channel1 {
     }
 
     /// 0xFF12 | NR12 - Channel 1 Volume Envelope
-    pub fn envelope(&self) -> u8 {
+    pub(crate) fn envelope(&self) -> u8 {
         u8::from(self.envelope)
     }
 

src/bus.rs

@@ -19,12 +19,12 @@ pub struct Bus {
     ppu: Ppu,
     work_ram: WorkRam,
     var_ram: VariableWorkRam,
-    pub(crate) timer: Timer,
+    timer: Timer,
     int: Interrupt,
-    pub(crate) apu: Apu,
+    apu: Apu,
     high_ram: HighRam,
     serial: Serial,
-    pub(crate) joypad: Joypad,
+    joypad: Joypad,
 }
 
 impl Default for Bus {
@@ -103,6 +103,11 @@ impl Bus {
         self.cart.as_mut()
     }
 
+    #[inline]
+    pub(crate) fn apu_mut(&mut self) -> &mut Apu {
+        &mut self.apu
+    }
+
     #[inline]
     pub fn ppu(&self) -> &Ppu {
         &self.ppu
@@ -110,7 +115,7 @@ impl Bus {
 }
 
 impl Bus {
-    pub fn oam_read_byte(&self, addr: u16) -> u8 {
+    pub(crate) fn oam_read_byte(&self, addr: u16) -> u8 {
         match addr {
             0x0000..=0x7FFF => {
                 // 16KB ROM bank 00 (ends at 0x3FFF)
@@ -157,7 +162,7 @@ impl Bus {
         }
     }
 
-    pub fn oam_write_byte(&mut self, addr: u16, byte: u8) {
+    pub(crate) fn oam_write_byte(&mut self, addr: u16, byte: u8) {
         self.ppu.oam.write_byte(addr, byte);
     }
 }

src/cpu.rs

@@ -103,7 +103,7 @@ impl Cpu {
     /// routine.
     ///
     /// Handle HALT and interrupts.
-    pub fn step(&mut self) -> Cycle {
+    pub(crate) fn step(&mut self) -> Cycle {
         // Log instructions
         // if self.reg.pc > 0xFF {
         //     let out = std::io::stdout();

src/emu.rs

@@ -90,7 +90,7 @@ impl Emulator {
     }
 
     pub fn set_prod(&mut self, prod: SampleProducer<f32>) {
-        self.cpu.bus_mut().apu.attach_producer(prod)
+        self.cpu.bus_mut().apu_mut().attach_producer(prod)
     }
 
     pub fn title(&self) -> &str {

src/instruction.rs

@@ -1893,7 +1893,7 @@ mod table {
     }
 
     impl Group1RegisterPair {
-        pub fn as_register_pair(&self) -> RegisterPair {
+        pub(crate) fn as_register_pair(&self) -> RegisterPair {
             use Group1RegisterPair::*;
 
             match self {
@@ -1927,7 +1927,7 @@ mod table {
     }
 
     impl Group2RegisterPair {
-        pub fn as_register_pair(&self) -> RegisterPair {
+        pub(crate) fn as_register_pair(&self) -> RegisterPair {
             use Group2RegisterPair::*;
 
             match self {
@@ -1961,7 +1961,7 @@ mod table {
     }
 
     impl Group3RegisterPair {
-        pub fn as_register_pair(&self) -> RegisterPair {
+        pub(crate) fn as_register_pair(&self) -> RegisterPair {
             use Group3RegisterPair::*;
 
             match self {
@@ -2003,7 +2003,7 @@ mod table {
     }
 
     impl Register {
-        pub fn cpu_register(&self) -> CpuRegister {
+        pub(crate) fn cpu_register(&self) -> CpuRegister {
             use Register::*;
 
             match self {

src/joypad.rs

@@ -111,7 +111,7 @@ impl ButtonEvent {
 }
 
 #[inline]
-pub fn handle_keyboard_input(pad: &mut Joypad, input: &WinitInputHelper) {
+pub(crate) fn handle_keyboard_input(pad: &mut Joypad, input: &WinitInputHelper) {
     use winit::event::VirtualKeyCode;
 
     // TODO: What do I have to do to get a match statement here?
@@ -177,7 +177,7 @@ pub fn handle_keyboard_input(pad: &mut Joypad, input: &WinitInputHelper) {
 }
 
 #[inline]
-pub fn handle_gamepad_input(pad: &mut Joypad, event: GamepadEvent) {
+pub(crate) fn handle_gamepad_input(pad: &mut Joypad, event: GamepadEvent) {
     use Button::*;
     use GamepadEventType::*;