chore: improve code clarity

src/Bus.zig

@@ -7,14 +7,15 @@ const Ppu = @import("ppu.zig").Ppu;
 const Scheduler = @import("scheduler.zig").Scheduler;
 
 const Allocator = std.mem.Allocator;
+const Self = @This();
 
 pak: GamePak,
 bios: Bios,
 ppu: Ppu,
 io: Io,
 
-pub fn init(alloc: Allocator, sched: *Scheduler, path: []const u8) !@This() {
+pub fn init(alloc: Allocator, sched: *Scheduler, path: []const u8) !Self {
-    return @This(){
+    return Self{
         .pak = try GamePak.init(alloc, path),
         .bios = try Bios.init(alloc, "./bin/gba_bios.bin"), // TODO: don't hardcode this + bundle open-sorce Boot ROM
         .ppu = try Ppu.init(alloc, sched),
@@ -22,13 +23,13 @@ pub fn init(alloc: Allocator, sched: *Scheduler, path: []const u8) !@This() {
     };
 }
 
-pub fn deinit(self: @This()) void {
+pub fn deinit(self: Self) void {
     self.pak.deinit();
     self.bios.deinit();
     self.ppu.deinit();
 }
 
-pub fn read32(self: *const @This(), addr: u32) u32 {
+pub fn read32(self: *const Self, addr: u32) u32 {
     return switch (addr) {
         // General Internal Memory
         0x0000_0000...0x0000_3FFF => self.bios.get32(@as(usize, addr)),
@@ -53,7 +54,7 @@ pub fn read32(self: *const @This(), addr: u32) u32 {
     };
 }
 
-pub fn write32(self: *@This(), addr: u32, word: u32) void {
+pub fn write32(self: *Self, addr: u32, word: u32) void {
     // TODO: write32 can write to GamePak Flash
 
     switch (addr) {
@@ -71,7 +72,7 @@ pub fn write32(self: *@This(), addr: u32, word: u32) void {
     }
 }
 
-pub fn read16(self: *const @This(), addr: u32) u16 {
+pub fn read16(self: *const Self, addr: u32) u16 {
     return switch (addr) {
         // General Internal Memory
         0x0000_0000...0x0000_3FFF => self.bios.get16(@as(usize, addr)),
@@ -96,7 +97,7 @@ pub fn read16(self: *const @This(), addr: u32) u16 {
     };
 }
 
-pub fn write16(self: *@This(), addr: u32, halfword: u16) void {
+pub fn write16(self: *Self, addr: u32, halfword: u16) void {
     // TODO: write16 can write to GamePak Flash
     switch (addr) {
         // General Internal Memory
@@ -113,7 +114,7 @@ pub fn write16(self: *@This(), addr: u32, halfword: u16) void {
     }
 }
 
-pub fn read8(self: *const @This(), addr: u32) u8 {
+pub fn read8(self: *const Self, addr: u32) u8 {
     return switch (addr) {
         // General Internal Memory
         0x0000_0000...0x0000_3FFF => self.bios.get8(@as(usize, addr)),
@@ -139,7 +140,7 @@ pub fn read8(self: *const @This(), addr: u32) u8 {
     };
 }
 
-pub fn write8(_: *@This(), addr: u32, byte: u8) void {
+pub fn write8(_: *Self, addr: u32, byte: u8) void {
     switch (addr) {
         // General Internal Memory
         0x0200_0000...0x0203_FFFF => std.debug.panic("[Bus:8] write 0x{X:} to 0x{X:} in IWRAM", .{ byte, addr }),

src/cpu.zig

@@ -16,12 +16,14 @@ pub const InstrFn = fn (*Arm7tdmi, *Bus, u32) void;
 const arm_lut: [0x1000]InstrFn = populate();
 
 pub const Arm7tdmi = struct {
+    const Self = @This();
+
     r: [16]u32,
     sched: *Scheduler,
     bus: *Bus,
     cpsr: CPSR,
 
-    pub fn init(sched: *Scheduler, bus: *Bus) @This() {
+    pub fn init(sched: *Scheduler, bus: *Bus) Self {
         return .{
             .r = [_]u32{0x00} ** 16,
             .sched = sched,
@@ -30,7 +32,7 @@ pub const Arm7tdmi = struct {
         };
     }
 
-    pub fn skipBios(self: *@This()) void {
+    pub fn skipBios(self: *Self) void {
         self.r[0] = 0x08000000;
         self.r[1] = 0x000000EA;
         // GPRs 2 -> 12 *should* already be 0 initialized
@@ -43,7 +45,7 @@ pub const Arm7tdmi = struct {
         self.cpsr.raw = 0x6000001F;
     }
 
-    pub inline fn step(self: *@This()) u64 {
+    pub inline fn step(self: *Self) u64 {
         const opcode = self.fetch();
         // self.mgbaLog(opcode);
 
@@ -51,17 +53,17 @@ pub const Arm7tdmi = struct {
         return 1;
     }
 
-    fn fetch(self: *@This()) u32 {
+    fn fetch(self: *Self) u32 {
         const word = self.bus.read32(self.r[15]);
         self.r[15] += 4;
         return word;
     }
 
-    pub fn fakePC(self: *const @This()) u32 {
+    pub fn fakePC(self: *const Self) u32 {
         return self.r[15] + 4;
     }
 
-    fn mgbaLog(self: *const @This(), opcode: u32) void {
+    fn mgbaLog(self: *const Self, opcode: u32) void {
         const stderr = std.io.getStdErr().writer();
         std.debug.getStderrMutex().lock();
         defer std.debug.getStderrMutex().unlock();

src/ppu.zig

@@ -11,17 +11,19 @@ pub const buf_pitch = width * @sizeOf(u16);
 const buf_len = buf_pitch * height;
 
 pub const Ppu = struct {
+    const Self = @This();
+
     vram: Vram,
     palette: Palette,
     sched: *Scheduler,
     frame_buf: []u8,
     alloc: Allocator,
 
-    pub fn init(alloc: Allocator, sched: *Scheduler) !@This() {
+    pub fn init(alloc: Allocator, sched: *Scheduler) !Self {
         // Queue first Hblank
-        sched.push(.{ .kind = .Draw, .tick = sched.tick + 240 * 4 });
+        sched.push(.Draw, sched.tick + (240 * 4));
 
-        return @This(){
+        return Self{
             .vram = try Vram.init(alloc),
             .palette = try Palette.init(alloc),
             .sched = sched,
@@ -30,13 +32,13 @@ pub const Ppu = struct {
         };
     }
 
-    pub fn deinit(self: @This()) void {
+    pub fn deinit(self: Self) void {
         self.alloc.free(self.frame_buf);
         self.vram.deinit();
         self.palette.deinit();
     }
 
-    pub fn drawScanline(self: *@This(), io: *const Io) void {
+    pub fn drawScanline(self: *Self, io: *const Io) void {
         const bg_mode = io.dispcnt.bg_mode.read();
         const scanline = io.vcount.scanline.read();
 
@@ -54,77 +56,81 @@ pub const Ppu = struct {
 };
 
 const Palette = struct {
+    const Self = @This();
+
     buf: []u8,
     alloc: Allocator,
 
-    fn init(alloc: Allocator) !@This() {
+    fn init(alloc: Allocator) !Self {
-        return @This(){
+        return Self{
             .buf = try alloc.alloc(u8, 0x400),
             .alloc = alloc,
         };
     }
 
-    fn deinit(self: @This()) void {
+    fn deinit(self: Self) void {
         self.alloc.free(self.buf);
     }
 
-    pub inline fn get32(self: *const @This(), idx: usize) u32 {
+    pub inline fn get32(self: *const Self, idx: usize) u32 {
         return (@as(u32, self.get16(idx + 2)) << 16) | @as(u32, self.get16(idx));
     }
 
-    pub inline fn set32(self: *@This(), idx: usize, word: u32) void {
+    pub inline fn set32(self: *Self, idx: usize, word: u32) void {
         self.set16(idx + 2, @truncate(u16, word >> 16));
         self.set16(idx, @truncate(u16, word));
     }
 
-    pub inline fn get16(self: *const @This(), idx: usize) u16 {
+    pub inline fn get16(self: *const Self, idx: usize) u16 {
         return (@as(u16, self.buf[idx + 1]) << 8) | @as(u16, self.buf[idx]);
     }
 
-    pub inline fn set16(self: *@This(), idx: usize, halfword: u16) void {
+    pub inline fn set16(self: *Self, idx: usize, halfword: u16) void {
         self.buf[idx + 1] = @truncate(u8, halfword >> 8);
         self.buf[idx] = @truncate(u8, halfword);
     }
 
-    pub inline fn get8(self: *const @This(), idx: usize) u8 {
+    pub inline fn get8(self: *const Self, idx: usize) u8 {
         return self.buf[idx];
     }
 };
 
 const Vram = struct {
+    const Self = @This();
+
     buf: []u8,
     alloc: Allocator,
 
-    fn init(alloc: Allocator) !@This() {
+    fn init(alloc: Allocator) !Self {
-        return @This(){
+        return Self{
             .buf = try alloc.alloc(u8, 0x18000),
             .alloc = alloc,
         };
     }
 
-    fn deinit(self: @This()) void {
+    fn deinit(self: Self) void {
         self.alloc.free(self.buf);
     }
 
-    pub inline fn get32(self: *const @This(), idx: usize) u32 {
+    pub inline fn get32(self: *const Self, idx: usize) u32 {
         return (@as(u32, self.get16(idx + 2)) << 16) | @as(u32, self.get16(idx));
     }
 
-    pub inline fn set32(self: *@This(), idx: usize, word: u32) void {
+    pub inline fn set32(self: *Self, idx: usize, word: u32) void {
         self.set16(idx + 2, @truncate(u16, word >> 16));
         self.set16(idx, @truncate(u16, word));
     }
 
-    pub inline fn get16(self: *const @This(), idx: usize) u16 {
+    pub inline fn get16(self: *const Self, idx: usize) u16 {
         return (@as(u16, self.buf[idx + 1]) << 8) | @as(u16, self.buf[idx]);
     }
 
-    pub inline fn set16(self: *@This(), idx: usize, halfword: u16) void {
+    pub inline fn set16(self: *Self, idx: usize, halfword: u16) void {
         self.buf[idx + 1] = @truncate(u8, halfword >> 8);
         self.buf[idx] = @truncate(u8, halfword);
     }
 
-    pub inline fn get8(self: *const @This(), idx: usize) u8 {
+    pub inline fn get8(self: *const Self, idx: usize) u8 {
         return self.buf[idx];
     }
 };

src/scheduler.zig

@@ -8,29 +8,28 @@ const PriorityQueue = std.PriorityQueue;
 const Allocator = std.mem.Allocator;
 
 pub const Scheduler = struct {
+    const Self = @This();
+
     tick: u64,
     queue: PriorityQueue(Event, void, lessThan),
 
-    pub fn init(alloc: Allocator) @This() {
+    pub fn init(alloc: Allocator) Self {
-        var scheduler = Scheduler{ .tick = 0, .queue = PriorityQueue(Event, void, lessThan).init(alloc, {}) };
+        var sched = Self{ .tick = 0, .queue = PriorityQueue(Event, void, lessThan).init(alloc, {}) };
+        sched.push(.HeatDeath, std.math.maxInt(u64));
 
-        scheduler.queue.add(.{
+        return sched;
-            .kind = EventKind.HeatDeath,
-            .tick = std.math.maxInt(u64),
-        }) catch unreachable;
-
-        return scheduler;
     }
 
-    pub fn deinit(self: @This()) void {
+    pub fn deinit(self: Self) void {
         self.queue.deinit();
     }
 
-    pub fn handleEvent(self: *@This(), _: *Arm7tdmi, bus: *Bus) void {
+    pub fn handleEvent(self: *Self, _: *Arm7tdmi, bus: *Bus) void {
         const should_handle = if (self.queue.peek()) |e| self.tick >= e.tick else false;
 
         if (should_handle) {
             const event = self.queue.remove();
+            std.log.info("[Scheduler] Handle {} at {} ticks", .{ event.kind, self.tick });
 
             switch (event.kind) {
                 .HeatDeath => {
@@ -49,11 +48,11 @@ pub const Scheduler = struct {
 
                     if (new_scanline < 160) {
                         // Transitioning to another Draw
-                        self.push(.{ .kind = .Draw, .tick = self.tick + (240 * 4) });
+                        self.push(.Draw, self.tick + (240 * 4));
                     } else {
                         // Transitioning to a Vblank
                         bus.io.dispstat.vblank.set();
-                        self.push(.{ .kind = .VBlank, .tick = self.tick + (308 * 4) });
+                        self.push(.VBlank, self.tick + (308 * 4));
                     }
                 },
                 .Draw => {
@@ -61,7 +60,7 @@ pub const Scheduler = struct {
 
                     // Transitioning to a Hblank
                     bus.io.dispstat.hblank.set();
-                    self.push(.{ .kind = .HBlank, .tick = self.tick + (68 * 4) });
+                    self.push(.HBlank, self.tick + (68 * 4));
                 },
                 .VBlank => {
                     // The end of a Vblank
@@ -72,24 +71,24 @@ pub const Scheduler = struct {
 
                     if (new_scanline < 228) {
                         // Transition to another Vblank
-                        self.push(.{ .kind = .VBlank, .tick = self.tick + (308 * 4) });
+                        self.push(.VBlank, self.tick + (308 * 4));
                     } else {
                         // Transition to another Draw
                         bus.io.vcount.scanline.write(0); // Reset Scanline
 
                         bus.io.dispstat.vblank.unset();
-                        self.push(.{ .kind = .Draw, .tick = self.tick + (240 * 4) });
+                        self.push(.Draw, self.tick + (240 * 4));
                     }
                 },
             }
         }
     }
 
-    pub inline fn push(self: *@This(), event: Event) void {
+    pub inline fn push(self: *Self, kind: EventKind, end: u64) void {
-        self.queue.add(event) catch unreachable;
+        self.queue.add(.{ .kind = kind, .tick = end }) catch unreachable;
     }
 
-    pub inline fn nextTimestamp(self: *@This()) u64 {
+    pub inline fn nextTimestamp(self: *Self) u64 {
         if (self.queue.peek()) |e| {
             return e.tick;
         } else unreachable;