feat: add keypad support

src/main.rs

@@ -10,7 +10,7 @@ pub mod state;
 pub mod window;
 
 fn main() -> Result<()> {
-    let window = Window::new(
+    let mut window = Window::new(
         "chip8",
         640,
         320,
@@ -21,9 +21,11 @@ fn main() -> Result<()> {
         },
     )
     .unwrap_or_else(|err| panic!("Failed to create window: {}", err));
+    window.limit_update_rate(Some(std::time::Duration::from_secs(1 / 60)));
+
     let mut state = State::new(window);
 
-    let program = read_program_from_file(Path::new("./tests/bin/3-corax+.ch8"))?;
+    let program = read_program_from_file(Path::new("./tests/bin/6-keypad.ch8"))?;
     state.load_program(&program);
 
     while state.display_open() {

src/state.rs

@@ -156,17 +156,17 @@ where
                 }
             }
             SkipIfKey { key_register } => {
-                if self.keys[self.variables[key_register] as usize] {
+                if self.window.is_key_down(self.variables[key_register]) {
                     self.pc += 2;
                 }
             }
             SkipIfNotKey { key_register } => {
-                if !self.keys[self.variables[key_register] as usize] {
+                if !self.window.is_key_down(self.variables[key_register]) {
                     self.pc += 2;
                 }
             }
             GetKey { dest } => {
-                if let Some(key) = self.keys.iter().position(|&e| e) {
+                if let Some(key) = self.window.get_key() {
                     self.variables[dest] = key as u8;
                 } else {
                     self.pc -= 2;
@@ -233,7 +233,6 @@ where
                         let pixel = (sprite_row >> (7 - x_offset)) & 1;
                         let buffer_index = (y + y_offset) * DISPLAY_WIDTH + (x + x_offset);
                         self.display[buffer_index] ^= pixel;
-                        // NOTE: Update display here to get live drawing effect
                         self.variables[0xF] = pixel;
                     }
                 }

src/window/minifb.rs

@@ -47,13 +47,39 @@ fn keyval_to_key(key: u8) -> Option<Key> {
     }
 }
 
+fn key_to_keyval(key: &Key) -> Option<u8> {
+    use Key::*;
+    match key {
+        Key1 => Some(0x1),
+        Key2 => Some(0x2),
+        Key3 => Some(0x3),
+        Key4 => Some(0xC),
+
+        Q => Some(0x4),
+        W => Some(0x5),
+        E => Some(0x6),
+        R => Some(0xD),
+
+        A => Some(0x7),
+        S => Some(0x8),
+        D => Some(0x9),
+        F => Some(0xE),
+
+        Z => Some(0xA),
+        X => Some(0x0),
+        C => Some(0xB),
+        V => Some(0xF),
+
+        _ => None,
+    }
+}
+
 impl Input for Window {
-    fn get_keys(&self, keys: &mut [bool]) {
-        for key in 0u8..=0xF {
-            keys[key as usize] = self.is_key_pressed(
-                keyval_to_key(key).expect("All cases should be covered"),
-                KeyRepeat::No,
-            )
-        }
+    fn is_key_down(&self, keyval: u8) -> bool {
+        self.is_key_down(keyval_to_key(keyval).expect("Should not be called with bad keyval"))
+    }
+
+    fn get_key(&self) -> Option<u8> {
+        self.get_keys().iter().filter_map(key_to_keyval).nth(0)
     }
 }

src/window/mod.rs

@@ -7,5 +7,6 @@ pub trait Display {
 }
 
 pub trait Input {
-    fn get_keys(&self, keys: &mut [bool]);
+    fn is_key_down(&self, key: u8) -> bool;
+    fn get_key(&self) -> Option<u8>;
 }