add volume controls to SDL2 frontend

README.md

@@ -20,13 +20,18 @@ cd target/release
 ./nesrs <path-to-rom>
 ```
 Controls are bound to:
-- Z: B
-- X: A
-- A: Select
-- S: Start
-- Arrow keys: Up/Down/Left/Right
+- `Z`: B
+- `X`: A
+- `A`: Select
+- `S`: Start
+- `Arrow keys`: Up/Down/Left/Right
 
-There are 5 save state slots. Save states can be loaded with the number keys 1-5, and written with SHIFT + [number].
+Meta controls (Not controller inputs):
+- `Space`: Pause/unpause emulation
+- `[`: Decrease volume
+- `]`: Increase volume
+- `1-5`: Load save state [1-5]
+- `Shift+[1-5]`: Write save state to slot [1-5]
 
 ## Running the WASM frontend locally
 Ensure that you have [wasm-pack](https://rustwasm.github.io/wasm-pack/), [Node](https://nodejs.org/en) and [pnpm](https://pnpm.io/) installed.

emu/src/audio_sample_buffer.rs

@@ -45,6 +45,10 @@ impl AudioSampleBuffer {
  self.clear();
  }
 
+ pub fn volume(&self) -> f32 {
+ self.volume
+ }
+
  pub fn set_volume(&mut self, volume: f32) {
  self.volume = clamp(volume, 0.0, 1.0);
  }

emu/src/nes.rs

@@ -72,6 +72,10 @@ impl Nes {
  &mut self.audio_buffer
  }
 
+ pub fn volume(&self) -> f32 {
+ self.audio_buffer.volume()
+ }
+
  pub fn set_volume(&mut self, volume: f32) {
  self.audio_buffer.set_volume(volume);
  }

src/main.rs

@@ -139,6 +139,12 @@ pub fn main() -> Result<()> {
  };
  }
  }
+ Keycode::LeftBracket => {
+ nes.set_volume(nes.volume() - 0.05);
+ }
+ Keycode::RightBracket => {
+ nes.set_volume(nes.volume() + 0.05);
+ }
  _ => {}
  },
  _ => {}