Add pixels-rs and winit as dependencies

.gitignore

@@ -1,2 +1,3 @@
 /target
-/games
+/games
+/.vscode

Cargo.toml

@@ -8,3 +8,6 @@ edition = "2018"
 
 [dependencies]
 rand = "0.7.3"
+pixels = "0.0.4"
+winit = "0.22.2"
+winit_input_helper = "0.7.0"

src/emu.rs

@@ -15,12 +15,12 @@ pub struct Chip8 {
     memory: [u8; 4096],
     delay: Timer,
     sound: Timer,
-    display: Display,
+    pub display: Display,
 }
 
 impl Default for Chip8 {
     fn default() -> Self {
-        Chip8 {
+        let mut chip8 = Chip8 {
             opcode: 0,
             i: 0,
             pc: 0x200, // Progrm counter starts at 0x200
@@ -32,11 +32,33 @@ impl Default for Chip8 {
             delay: Default::default(),
             sound: Default::default(),
             display: Display::default(),
-        }
+        };
+
+        chip8.load_font_set();
+        chip8
     }
 }
 
 impl Chip8 {
+    const FONT_SET: [u8; 80] = [
+        0xF0, 0x90, 0x90, 0x90, 0xF0, // 0
+        0x20, 0x60, 0x20, 0x20, 0x70, // 1
+        0xF0, 0x10, 0xF0, 0x80, 0xF0, // 2
+        0xF0, 0x10, 0xF0, 0x10, 0xF0, // 3
+        0x90, 0x90, 0xF0, 0x10, 0x10, // 4
+        0xF0, 0x80, 0xF0, 0x10, 0xF0, // 5
+        0xF0, 0x80, 0xF0, 0x90, 0xF0, // 6
+        0xF0, 0x10, 0x20, 0x40, 0x40, // 7
+        0xF0, 0x90, 0xF0, 0x90, 0xF0, // 8
+        0xF0, 0x90, 0xF0, 0x10, 0xF0, // 9
+        0xF0, 0x90, 0xF0, 0x90, 0x90, // A
+        0xE0, 0x90, 0xE0, 0x90, 0xE0, // B
+        0xF0, 0x80, 0x80, 0x80, 0xF0, // C
+        0xE0, 0x90, 0x90, 0x90, 0xE0, // D
+        0xF0, 0x80, 0xF0, 0x80, 0xF0, // E
+        0xF0, 0x80, 0xF0, 0x80, 0x80, // F
+    ];
+
     pub fn execute_cycle(&mut self) {
         self.opcode = self.get_opcode();
         println!("{:#x}", self.opcode);
@@ -46,6 +68,12 @@ impl Chip8 {
         self.sound.tick();
     }
 
+    pub fn load_font_set(&mut self) {
+        for (i, byte) in Self::FONT_SET.iter().enumerate() {
+            self.memory[i] = *byte;
+        }
+    }
+
     pub fn load_rom<P: AsRef<Path>>(&mut self, path: P) -> Result<(), io::Error> {
         let mut file = File::open(path.as_ref())?;
         let mut rom_buf: Vec<u8> = vec![];
@@ -157,6 +185,7 @@ impl Chip8 {
     fn jmp_addr(&mut self, n_1: u16, n_2: u16, n_3: u16) {
         // sets the program counter to addr (nnn)
         self.pc = Self::convert_to_addr(n_1, n_2, n_3);
+        println!("{:#x}", self.pc);
     }
 
     fn ret(&mut self) {
@@ -203,7 +232,7 @@ impl Chip8 {
     fn add_vx_byte(&mut self, x: u16, k_1: u16, k_2: u16) {
         // calculate Vx + kk, then store it in Vx
         let x = x as usize;
-        self.v[x] = self.v[x] + Self::convert_to_byte(k_1, k_2);
+        self.v[x] = self.v[x].wrapping_add(Self::convert_to_byte(k_1, k_2));
     }
 
     fn ld_vx_vy(&mut self, x: u16, y: u16) {
@@ -247,7 +276,7 @@ impl Chip8 {
         let vy = self.v[y as usize];
 
         self.v[0xF as usize] = if vx > vy { 1 } else { 0 };
-        self.v[x as usize] = vx - vy;
+        self.v[x as usize] = vx.wrapping_sub(vy);
     }
 
     fn shr_vx(&mut self, x: u16) {
@@ -390,8 +419,9 @@ impl Chip8 {
         self.i = self.i + self.v[x as usize] as u16;
     }
 
-    fn ld_f_vx(&mut self, _x: u16) {
+    fn ld_f_vx(&mut self, x: u16) {
-        todo!("Implement 0xF_29");
+        // set I to location of hex sprite related to Vx
+        self.i = self.v[x as usize] as u16 * 5;
     }
 
     fn ld_b_vx(&mut self, x: u16) {
@@ -399,15 +429,15 @@ impl Chip8 {
         // take tens digit and place it at I + 1
         // take ones digit and place it at I + 2
         let i = self.i as usize;
-        let mut iter = Self::digits(self.v[x as usize]);
+        let mut iter = Self::digits(self.v[x as usize] as usize);
 
         let ones = iter.next().unwrap(); // Ther has to at least be a ones lol
         let tens = iter.next().unwrap_or(0);
         let hundreds = iter.next().unwrap_or(0);
 
-        self.memory[i] = hundreds;
+        self.memory[i] = hundreds as u8;
-        self.memory[i + 1] = tens;
+        self.memory[i + 1] = tens as u8;
-        self.memory[i + 2] = ones;
+        self.memory[i + 2] = ones as u8;
     }
 
     fn ld_i_vx(&mut self, x: u16) {
@@ -436,7 +466,7 @@ impl Chip8 {
     }
 
     // https://stackoverflow.com/questions/41536479/how-do-i-split-an-integer-into-individual-digits
-    fn digits(mut num: u8) -> impl Iterator<Item = u8> {
+    fn digits(mut num: usize) -> impl Iterator<Item = usize> {
         let mut divisor = 1;
         while num >= divisor * 10 {
             divisor *= 10;

src/main.rs

@@ -4,16 +4,78 @@
 use chip8::emu::Chip8;
 use std::path::Path;
 use std::time::Duration;
+
+use pixels::{wgpu::Surface, Error, Pixels, SurfaceTexture};
+use winit::dpi::LogicalSize;
+use winit::event::{Event, VirtualKeyCode};
+use winit::event_loop::{ControlFlow, EventLoop};
+use winit::window::WindowBuilder;
+use winit_input_helper::WinitInputHelper;
+
+static WIDTH: u32 = 64;
+static HEIGHT: u32 = 32;
+
 fn main() {
+    let event_loop = EventLoop::new();
+    let mut input = WinitInputHelper::new();
+    let window = {
+        let size = LogicalSize::new(WIDTH as f64, HEIGHT as f64);
+        WindowBuilder::new()
+            .with_title("Chip8 Emulator")
+            .with_inner_size(size)
+            .with_min_inner_size(size)
+            .build(&event_loop)
+            .unwrap()
+    };
+
+    let mut hidpi_factor = window.scale_factor();
+
+    let mut pixels = {
+        let surface = Surface::create(&window);
+        let surface_texture = SurfaceTexture::new(WIDTH, HEIGHT, surface);
+        Pixels::new(WIDTH, HEIGHT, surface_texture).unwrap()
+    };
+
     let mut chip8: Chip8 = Default::default();
 
     chip8
-        .load_rom(Path::new("./games/c8games/TICTAC"))
+        .load_rom(Path::new("./games/test_opcode.ch8"))
         .expect("Unable to load ROM");
 
-    loop {
+    event_loop.run(move |event, _, control_flow| {
         chip8.execute_cycle();
 
-        std::thread::sleep(Duration::from_millis(300));
+        draw(&chip8.display.buf, pixels.get_frame());
+        pixels.render().unwrap();
+        window.request_redraw();
+
+        if input.update(&event) {
+            if let Some(factor) = input.scale_factor_changed() {
+                hidpi_factor = factor;
+            };
+
+            if input.key_pressed(VirtualKeyCode::Escape) || input.quit() {
+                *control_flow = ControlFlow::Exit;
+                return;
+            }
+
+            if let Some(size) = input.window_resized() {
+                pixels.resize(size.width, size.height);
+            }
+        }
+
+        // std::thread::sleep(Duration::from_millis(1000));
+    });
+}
+
+fn draw(chip8_gfx: &[u8], frame: &mut [u8]) {
+    for (i, pixel) in frame.chunks_exact_mut(4).enumerate() {
+        let rgba = if chip8_gfx[i] != 0 {
+            [0xFF, 0xFF, 0xFF, 0xFF]
+        } else {
+            [0x00, 0x00, 0x00, 0xFF]
+        };
+
+        pixel.copy_from_slice(&rgba);
     }
 }