chore: add minimum zig version

still not ideal imo

.github/workflows/main.yml

@@ -4,6 +4,7 @@ on:
   push:
     paths:
       - "**.zig"
+      - "dl_sdl2.ps1"
     branches:
       - main
   schedule:
@@ -14,13 +15,17 @@ jobs:
   build:
     strategy:
       matrix:
-        os: [ubuntu-latest, windows-latest, macos-latest]
-        # os: [ubuntu-latest, windows-latest]
+        os: [ubuntu-latest, windows-latest] # TODO: Figure out Apple Silicon macOS
     runs-on: ${{matrix.os}}
     steps:
       - uses: goto-bus-stop/setup-zig@v2
         with:
-          version: 0.11.0
+          version: 0.13.0
+      - run: |
+            git config --global core.autocrlf false
+      - uses: actions/checkout@v3
+        with:
+          submodules: recursive
       - name: prepare-linux
         if: runner.os == 'Linux'
         run: |
@@ -29,26 +34,19 @@ jobs:
       - name: prepare-windows
         if: runner.os == 'Windows'
         run: |
-            vcpkg integrate install
-            vcpkg install sdl2:x64-windows
-            git config --global core.autocrlf false
+            .\dl_sdl2.ps1
       - name: prepare-macos
         if: runner.os == 'macOS'
         run: |
             brew install sdl2
-      - uses: actions/checkout@v3
-        with:
-          submodules: recursive
       - name: build 
         run: zig build -Doptimize=ReleaseSafe -Dcpu=baseline
-      - name: prepare-executable
-        run: |
-            mv zig-out/lib/* zig-out/bin
       - name: upload
         uses: actions/upload-artifact@v3
         with:
           name: zba-${{matrix.os}}
-          path: zig-out/bin
+          path: zig-out
+
   lint:
     runs-on: ubuntu-latest
     steps: 
@@ -57,6 +55,5 @@ jobs:
           submodules: recursive
       - uses: goto-bus-stop/setup-zig@v2
         with:
-          version: 0.11.0-dev.3395+1e7dcaa3a
-      - run: zig fmt src/**/*.zig
-  
+          version: 0.13.0
+      - run: zig fmt --check {src,lib}/**/*.zig build.zig build.zig.zon

.gitignore

@@ -1,6 +1,7 @@
 /.vscode
 /bin
 **/zig-cache
+**/.zig-cache
 **/zig-out
 /docs
 **/*.log
@@ -15,4 +16,4 @@
 
 
 # Dear ImGui
-**/imgui.ini
+**/imgui.ini

.gitmodules

@@ -1,6 +1,3 @@
 [submodule "lib/SDL.zig"]
 	path = lib/SDL.zig
-	url = https://github.com/MasterQ32/SDL.zig
-[submodule "lib/zgui"]
-	path = lib/zgui
-	url = https://git.musuka.dev/paoda/zgui
+	url = https://github.com/paoda/SDL.zig

build.zig

@@ -1,15 +1,16 @@
 const std = @import("std");
 const builtin = @import("builtin");
 
-const Sdk = @import("lib/SDL.zig/Sdk.zig");
-const zgui = @import("lib/zgui/build.zig");
+const sdl = @import("lib/SDL.zig/build.zig");
+
+const SemVer = std.SemanticVersion;
+
+const target_version = "0.13.0";
 
 pub fn build(b: *std.Build) void {
-    // Minimum Zig Version
-    const min_ver = std.SemanticVersion.parse("0.11.0") catch return; // https://github.com/ziglang/zig/tree/0.11.0
-    if (builtin.zig_version.order(min_ver).compare(.lt)) {
-        std.log.err("{s}", .{b.fmt("Zig v{} does not meet the minimum version requirement. (Zig v{})", .{ builtin.zig_version, min_ver })});
-        std.os.exit(1);
+    const actual_version = builtin.zig_version;
+    if (comptime actual_version.order(SemVer.parse(target_version) catch unreachable) != .eq) {
+        @compileError("ZBA must be built with Zig v" ++ target_version ++ ".");
     }
 
     const target = b.standardTargetOptions(.{});
@@ -17,51 +18,45 @@ pub fn build(b: *std.Build) void {
 
     const exe = b.addExecutable(.{
         .name = "zba",
-        .root_source_file = .{ .path = "src/main.zig" },
+        .root_source_file = b.path("src/main.zig"),
         .target = target,
         .optimize = optimize,
     });
-    exe.main_pkg_path = .{ .path = "." }; // Necessary so that src/main.zig can embed example.toml
 
-    exe.addModule("known_folders", b.dependency("known-folders", .{}).module("known-folders")); // https://github.com/ziglibs/known-folders
-    exe.addModule("datetime", b.dependency("zig-datetime", .{}).module("zig-datetime")); // https://github.com/frmdstryr/zig-datetime
-    exe.addModule("clap", b.dependency("zig-clap", .{}).module("clap")); // https://github.com/Hejsil/zig-clap
-    exe.addModule("gdbstub", b.dependency("zba-gdbstub", .{}).module("gdbstub")); // https://git.musuka.dev/paoda/zba-gdbstub
-    exe.addModule("zba-util", b.dependency("zba-util", .{}).module("zba-util")); // https://git.musuka.dev/paoda/zba-util
-    exe.addModule("tomlz", b.dependency("tomlz", .{}).module("tomlz")); // https://github.com/mattyhall/tomlz
-    exe.addModule("arm32", b.dependency("arm32", .{}).module("arm32")); // https://git.musuka.dev/paoda/arm32
+    const sdk = sdl.init(b, null, null);
+    const zgui = b.dependency("zgui", .{ .shared = false, .with_implot = true, .backend = .sdl2_opengl3 });
+    const imgui = zgui.artifact("imgui");
 
-    // https://github.com/fabioarnold/nfd-zig
-    const nfd_dep = b.dependency("nfd", .{ .target = target, .optimize = optimize });
-    exe.linkLibrary(nfd_dep.artifact("nfd"));
-    exe.addModule("nfd", nfd_dep.module("nfd"));
+    exe.root_module.addImport("known_folders", b.dependency("known-folders", .{}).module("known-folders")); // https://github.com/ziglibs/known-folders
+    exe.root_module.addImport("datetime", b.dependency("zig-datetime", .{}).module("zig-datetime")); // https://github.com/frmdstryr/zig-datetime
+    exe.root_module.addImport("clap", b.dependency("zig-clap", .{}).module("clap")); // https://github.com/Hejsil/zig-clap
+    exe.root_module.addImport("zba-util", b.dependency("zba-util", .{}).module("zba-util")); // https://git.musuka.dev/paoda/zba-util
+    exe.root_module.addImport("tomlz", b.dependency("tomlz", .{}).module("tomlz")); // https://github.com/mattyhall/tomlz
+    exe.root_module.addImport("arm32", b.dependency("arm32", .{}).module("arm32")); // https://git.musuka.dev/paoda/arm32
+    exe.root_module.addImport("gdbstub", b.dependency("zba-gdbstub", .{}).module("zba-gdbstub")); // https://git.musuka.dev/paoda/gdbstub
+    exe.root_module.addImport("nfd", b.dependency("nfd", .{}).module("nfd")); // https://github.com/fabioarnold/nfd-zig
+    exe.root_module.addImport("zgui", zgui.module("root")); // https://git.musuka.dev/paoda/zgui
+    exe.root_module.addImport("sdl2", sdk.getNativeModule()); // https://github.com/MasterQ32/SDL.zig
 
-    // https://github.com/MasterQ32/SDL.zig
-    const sdk = Sdk.init(b, null);
-    sdk.link(exe, .dynamic);
-    exe.addModule("sdl2", sdk.getNativeModule());
+    exe.root_module.addAnonymousImport("bitfield", .{ .root_source_file = b.path("lib/bitfield.zig") }); // https://github.com/FlorenceOS/
+    exe.root_module.addAnonymousImport("gl", .{ .root_source_file = b.path("lib/gl.zig") }); // https://github.com/MasterQ32/zig-opengl
+    exe.root_module.addAnonymousImport("example.toml", .{ .root_source_file = b.path("example.toml") });
 
-    // https://git.musuka.dev/paoda/zgui
-    // .shared option should stay in sync with SDL.zig call above where true == .dynamic, and false == .static
-    const zgui_pkg = zgui.package(b, target, optimize, .{ .options = .{ .backend = .sdl2_opengl3, .shared = true } });
-    zgui_pkg.link(exe);
-
-    exe.addAnonymousModule("bitfield", .{ .source_file = .{ .path = "lib/bitfield.zig" } }); // https://github.com/FlorenceOS/
-    exe.addAnonymousModule("gl", .{ .source_file = .{ .path = "lib/gl.zig" } }); // https://github.com/MasterQ32/zig-opengl
+    sdk.link(exe, .dynamic, .SDL2);
+    sdk.link(imgui, .dynamic, .SDL2);
+    exe.linkLibrary(imgui);
 
     b.installArtifact(exe);
 
     const run_cmd = b.addRunArtifact(exe);
     run_cmd.step.dependOn(b.getInstallStep());
-    if (b.args) |args| {
-        run_cmd.addArgs(args);
-    }
+    if (b.args) |args| run_cmd.addArgs(args);
 
     const run_step = b.step("run", "Run the app");
     run_step.dependOn(&run_cmd.step);
 
     const exe_tests = b.addTest(.{
-        .root_source_file = .{ .path = "src/main.zig" },
+        .root_source_file = b.path("src/main.zig"),
         .target = target,
         .optimize = optimize,
     });

build.zig.zon

@@ -1,38 +1,50 @@
 .{
     .name = "zba",
     .version = "0.1.0",
+    .paths = .{
+        "build.zig",
+        "build.zig.zon",
+        "lib/bitfield.zig",
+        "lib/gl.zig",
+        "src",
+    },
+    .minimum_zig_version = "0.13.0",
     .dependencies = .{
         .nfd = .{
-            .url = "https://github.com/paoda/nfd-zig/archive/3333a86186a0cb9fbf57823ac416aa77d472db61.tar.gz",
-            .hash = "12201079ca80d9a7cfe9f2f3ffe4d5e92627a48dfdec5dd3c8cf9a1609f746a9e17f",
+            .url = "git+https://github.com/paoda/nfd-zig#ad81729d33da30d5f4fd23718debec48245121ca",
+            .hash = "1220a679380847513262c8c5c474d4a415f9ecc4921c8c6aefbdbdce66cf2aa19ceb",
         },
         .@"known-folders" = .{
-            .url = "https://github.com/ziglibs/known-folders/archive/fa75e1bc672952efa0cf06160bbd942b47f6d59b.tar.gz",
-            .hash = "122048992ca58a78318b6eba4f65c692564be5af3b30fbef50cd4abeda981b2e7fa5",
+            .url = "git+https://github.com/ziglibs/known-folders#1cceeb70e77dec941a4178160ff6c8d05a74de6f",
+            .hash = "12205f5e7505c96573f6fc5144592ec38942fb0a326d692f9cddc0c7dd38f9028f29",
         },
         .@"zig-datetime" = .{
-            .url = "https://github.com/frmdstryr/zig-datetime/archive/ddecb4e508e99ad6ab1314378225413959d54756.tar.gz",
-            .hash = "12202cbb909feb6b09164ac997307c6b1ab35cb05a846198cf41f7ec608d842c1761",
+            .url = "git+https://github.com/frmdstryr/zig-datetime#70aebf28fb3e137cd84123a9349d157a74708721",
+            .hash = "122077215ce36e125a490e59ec1748ffd4f6ba00d4d14f7308978e5360711d72d77f",
         },
         .@"zig-clap" = .{
-            .url = "https://github.com/Hejsil/zig-clap/archive/f49b94700e0761b7514abdca0e4f0e7f3f938a93.tar.gz",
-            .hash = "1220f48518ce22882e102255ed3bcdb7aeeb4891f50b2cdd3bd74b5b2e24d3149ba2",
-        },
-        .@"zba-gdbstub" = .{
-            .url = "https://git.musuka.dev/paoda/zba-gdbstub/archive/d3655e8f61a4943edfce40629dd2a82f9c7bf21c.tar.gz",
-            .hash = "122076f8e22bb55b555c9812d72d908419eda1bf07b6bb7a1f6d9ecb2bb2a49c56d0",
+            .url = "git+https://github.com/Hejsil/zig-clap#c0193e9247335a6c1688b946325060289405de2a",
+            .hash = "12207ee987ce045596cb992cfb15b0d6d9456e50d4721c3061c69dabc2962053644d",
         },
         .@"zba-util" = .{
-            .url = "https://git.musuka.dev/paoda/zba-util/archive/322c798e384a0d24cc84ffcfa2e4a3ca807798a0.tar.gz",
-            .hash = "12209ce0e729460b997706e47a53a32f1842672cd120189e612f4871731780a30ed0",
+            .url = "git+https://git.musuka.dev/paoda/zba-util#bf0e744047ce1ec90172dbcc0c72bfcc29a063e3",
+            .hash = "1220d044ecfbeacc3b3cebeff131d587e24167d61435a3cb96dffd4d4521bb06aed0",
+        },
+        .@"zba-gdbstub" = .{
+            .url = "git+https://git.musuka.dev/paoda/zba-gdbstub#9a50607d5f48293f950a4e823344f2bc24582a5a",
+            .hash = "1220ac267744ed2a735f03c4620d7c6210fbd36d7bfb2b376ddc3436faebadee0f61",
         },
         .tomlz = .{
-            .url = "https://github.com/mattyhall/tomlz/archive/47067cd7c902485f7d6e928331fd171ed47f72da.tar.gz",
-            .hash = "12205771687a4d42700c515ef32e4fadb8b4dbf9e3f941b0a0e6f8bde5ef6dbc27d6",
+            .url = "git+https://github.com/paoda/tomlz#9a16dd53927ef2012478b6494bafb4475e44f4c9",
+            .hash = "12204f922cab84980e36b5c058d354ec0ee169bda401c8e0e80a463580349b476569",
         },
         .arm32 = .{
-            .url = "https://git.musuka.dev/paoda/arm32/archive/ba22b856ecb3bd6fc43530dddf6ee79b4b458b30.tar.gz",
-            .hash = "1220f1cc3e23804eff5c68b93a4e77d948a9cfc3492d799d39f769d8c79b7c41d83e",
+            .url = "git+https://git.musuka.dev/paoda/arm32#814d081ea0983bc48841a6baad7158c157b17ad6",
+            .hash = "12203c3dacf3a7aa7aee5fc5763dd7b40399bd1c34d1483330b6bd5a76bffef22d82",
+        },
+        .zgui = .{
+            .url = "git+https://git.musuka.dev/paoda/zgui#7f8d05101e96c64314d7926c80ee157dcb89da4e",
+            .hash = "1220bd81a1c7734892b1d4233ed047710487787873c85dd5fc76d1764a331ed2ff43",
         },
     },
 }

dl_sdl2.ps1

@@ -0,0 +1,36 @@
+$SDL2Version = "2.30.0"
+$ArchiveFile = ".\SDL2-devel-mingw.zip"
+$Json = @"
+{
+	"x86_64-windows-gnu": {
+		"include": ".build_config\\SDL2\\include",
+		"libs": ".build_config\\SDL2\\lib",
+		"bin": ".build_config\\SDL2\\bin"
+	}
+}	
+"@
+
+New-Item -Force -ItemType Directory -Path .\.build_config
+Set-Location -Path .build_config -PassThru
+
+if (!(Test-Path -PathType Leaf $ArchiveFile)) {
+	Invoke-WebRequest "https://github.com/libsdl-org/SDL/releases/download/release-$SDL2Version/SDL2-devel-$SDL2Version-mingw.zip" -OutFile $ArchiveFile
+}
+
+Expand-Archive $ArchiveFile
+
+if (Test-Path -PathType Container .\SDL2) {
+	Remove-Item -Recurse .\SDL2
+}
+
+New-Item -Force -ItemType Directory -Path .\SDL2 
+Get-ChildItem -Path ".\SDL2-devel-mingw\SDL2-$SDL2Version\x86_64-w64-mingw32" | Move-Item -Destination .\SDL2
+
+# #include <SDL.h>
+Move-Item -Force -Path .\SDL2\include\SDL2\* -Destination .\SDL2\include
+Remove-Item -Force .\SDL2\include\SDL2
+
+New-Item -Force .\sdl.json -Value $Json
+
+Remove-Item -Recurse .\SDL2-devel-mingw
+Set-Location -Path .. -PassThru

src/core/apu/signal/Wave.zig

@@ -18,7 +18,7 @@ pub fn read(self: *const Self, comptime T: type, nr30: io.WaveSelect, addr: u32)
     const base = if (!nr30.bank.read()) @as(u32, 0x10) else 0; // Read from the Opposite Bank in Use
 
     const i = base + addr - 0x0400_0090;
-    return std.mem.readIntSliceLittle(T, self.buf[i..][0..@sizeOf(T)]);
+    return std.mem.readInt(T, self.buf[i..][0..@sizeOf(T)], .little);
 }
 
 pub fn write(self: *Self, comptime T: type, nr30: io.WaveSelect, addr: u32, value: T) void {
@@ -26,7 +26,7 @@ pub fn write(self: *Self, comptime T: type, nr30: io.WaveSelect, addr: u32, valu
     const base = if (!nr30.bank.read()) @as(u32, 0x10) else 0; // Write to the Opposite Bank in Use
 
     const i = base + addr - 0x0400_0090;
-    std.mem.writeIntSliceLittle(T, self.buf[i..][0..@sizeOf(T)], value);
+    std.mem.writeInt(T, self.buf[i..][0..@sizeOf(T)], value, .little);
 }
 
 pub fn init(sched: *Scheduler) Self {

src/core/bus/Bios.zig

@@ -51,7 +51,7 @@ fn _read(self: *const Self, comptime T: type, addr: u32) T {
     const buf = self.buf orelse std.debug.panic("[BIOS] ZBA tried to read {} from 0x{X:0>8} but not BIOS was present", .{ T, addr });
 
     return switch (T) {
-        u32, u16, u8 => std.mem.readIntSliceLittle(T, buf[addr..][0..@sizeOf(T)]),
+        u32, u16, u8 => std.mem.readInt(T, buf[addr..][0..@sizeOf(T)], .little),
         else => @compileError("BIOS: Unsupported read width"),
     };
 }

src/core/bus/Ewram.zig

@@ -11,7 +11,7 @@ pub fn read(self: *const Self, comptime T: type, address: usize) T {
     const addr = address & 0x3FFFF;
 
     return switch (T) {
-        u32, u16, u8 => std.mem.readIntSliceLittle(T, self.buf[addr..][0..@sizeOf(T)]),
+        u32, u16, u8 => std.mem.readInt(T, self.buf[addr..][0..@sizeOf(T)], .little),
         else => @compileError("EWRAM: Unsupported read width"),
     };
 }
@@ -20,7 +20,7 @@ pub fn write(self: *const Self, comptime T: type, address: usize, value: T) void
     const addr = address & 0x3FFFF;
 
     return switch (T) {
-        u32, u16, u8 => std.mem.writeIntSliceLittle(T, self.buf[addr..][0..@sizeOf(T)], value),
+        u32, u16, u8 => std.mem.writeInt(T, self.buf[addr..][0..@sizeOf(T)], value, .little),
         else => @compileError("EWRAM: Unsupported write width"),
     };
 }

src/core/bus/Iwram.zig

@@ -11,7 +11,7 @@ pub fn read(self: *const Self, comptime T: type, address: usize) T {
     const addr = address & 0x7FFF;
 
     return switch (T) {
-        u32, u16, u8 => std.mem.readIntSliceLittle(T, self.buf[addr..][0..@sizeOf(T)]),
+        u32, u16, u8 => std.mem.readInt(T, self.buf[addr..][0..@sizeOf(T)], .little),
         else => @compileError("IWRAM: Unsupported read width"),
     };
 }
@@ -20,7 +20,7 @@ pub fn write(self: *const Self, comptime T: type, address: usize, value: T) void
     const addr = address & 0x7FFF;
 
     return switch (T) {
-        u32, u16, u8 => std.mem.writeIntSliceLittle(T, self.buf[addr..][0..@sizeOf(T)], value),
+        u32, u16, u8 => std.mem.writeInt(T, self.buf[addr..][0..@sizeOf(T)], value, .little),
         else => @compileError("IWRAM: Unsupported write width"),
     };
 }

src/core/bus/backup/eeprom.zig

@@ -121,7 +121,7 @@ pub const Eeprom = struct {
                     .Large => {
                         if (self.writer.len() == 14) {
                             const addr: u10 = @intCast(self.writer.finish());
-                            const value = std.mem.readIntSliceLittle(u64, buf[@as(u13, addr) * 8 ..][0..8]);
+                            const value = std.mem.readInt(u64, buf[@as(u13, addr) * 8 ..][0..8], .little);
 
                             self.reader.configure(value);
                             self.state = .RequestEnd;
@@ -131,7 +131,7 @@ pub const Eeprom = struct {
                         if (self.writer.len() == 6) {
                             // FIXME: Duplicated code from above
                             const addr: u6 = @intCast(self.writer.finish());
-                            const value = std.mem.readIntSliceLittle(u64, buf[@as(u13, addr) * 8 ..][0..8]);
+                            const value = std.mem.readInt(u64, buf[@as(u13, addr) * 8 ..][0..8], .little);
 
                             self.reader.configure(value);
                             self.state = .RequestEnd;
@@ -159,7 +159,7 @@ pub const Eeprom = struct {
             },
             .WriteTransfer => {
                 if (self.writer.len() == 64) {
-                    std.mem.writeIntSliceLittle(u64, buf[self.addr * 8 ..][0..8], self.writer.finish());
+                    std.mem.writeInt(u64, buf[self.addr * 8 ..][0..8], self.writer.finish(), .little);
                     self.state = .RequestEnd;
                 }
             },

src/core/bus/io.zig

@@ -96,7 +96,7 @@ pub fn read(bus: *const Bus, comptime T: type, address: u32) ?T {
             0x0400_0128 => util.io.read.todo(log, "Read {} from SIOCNT", .{T}),
 
             // Keypad Input
-            0x0400_0130 => bus.io.keyinput.load(.Monotonic),
+            0x0400_0130 => bus.io.keyinput.load(.monotonic),
 
             // Serial Communication 2
             0x0400_0134 => util.io.read.todo(log, "Read {} from RCNT", .{T}),
@@ -382,7 +382,7 @@ pub const KeyInput = extern union {
 
 const AtomicKeyInput = struct {
     const Self = @This();
-    const Ordering = std.atomic.Ordering;
+    const AtomicOrder = std.builtin.AtomicOrder;
 
     inner: KeyInput,
 
@@ -390,18 +390,18 @@ const AtomicKeyInput = struct {
         return .{ .inner = value };
     }
 
-    pub inline fn load(self: *const Self, comptime ordering: Ordering) u16 {
+    pub inline fn load(self: *const Self, comptime ordering: AtomicOrder) u16 {
         return switch (ordering) {
-            .AcqRel, .Release => @compileError("not supported for atomic loads"),
+            .acq_rel, .release => @compileError("not supported for atomic loads"),
             else => @atomicLoad(u16, &self.inner.raw, ordering),
         };
     }
 
-    pub inline fn fetchOr(self: *Self, value: u16, comptime ordering: Ordering) void {
+    pub inline fn fetchOr(self: *Self, value: u16, comptime ordering: AtomicOrder) void {
         _ = @atomicRmw(u16, &self.inner.raw, .Or, value, ordering);
     }
 
-    pub inline fn fetchAnd(self: *Self, value: u16, comptime ordering: Ordering) void {
+    pub inline fn fetchAnd(self: *Self, value: u16, comptime ordering: AtomicOrder) void {
         _ = @atomicRmw(u16, &self.inner.raw, .And, value, ordering);
     }
 };

src/core/emu.zig

@@ -6,8 +6,7 @@ const Scheduler = @import("scheduler.zig").Scheduler;
 const Arm7tdmi = @import("arm32").Arm7tdmi;
 const Bus = @import("Bus.zig");
 const Tracker = @import("../util.zig").FpsTracker;
-
-pub const Message = enum { Pause, Resume, Quit };
+const Channel = @import("../util.zig").Queue;
 
 const stepDmaTransfer = @import("cpu_util.zig").stepDmaTransfer;
 const isHalted = @import("cpu_util.zig").isHalted;
@@ -15,15 +14,29 @@ const isHalted = @import("cpu_util.zig").isHalted;
 const Timer = std.time.Timer;
 
 pub const Synchro = struct {
-    const AtomicBool = std.atomic.Atomic(bool);
+    const AtomicBool = std.atomic.Value(bool);
 
-    // UI -> Emulator
-    ui_busy: *AtomicBool,
-    paused: *AtomicBool, // FIXME: can ui_busy and paused be the same?
-    should_quit: *AtomicBool,
+    // FIXME: This Enum ends up being really LARGE!!!
+    pub const Message = union(enum) {
+        rom_path: [std.fs.MAX_PATH_BYTES]u8,
+        bios_path: [std.fs.MAX_PATH_BYTES]u8,
+        restart: void,
+    };
 
-    // Emulator -> UI
-    did_pause: *AtomicBool,
+    paused: AtomicBool = AtomicBool.init(true), // FIXME: can ui_busy and paused be the same?
+    should_quit: AtomicBool = AtomicBool.init(false),
+
+    ch: Channel(Message),
+
+    pub fn init(allocator: std.mem.Allocator) !@This() {
+        const msg_buf = try allocator.alloc(Message, 1);
+        return .{ .ch = Channel(Message).init(msg_buf) };
+    }
+
+    pub fn deinit(self: *@This(), allocator: std.mem.Allocator) void {
+        allocator.free(self.ch.inner.buf);
+        self.* = undefined;
+    }
 };
 
 /// 4 Cycles in 1 dot
@@ -52,7 +65,7 @@ const RunKind = enum {
     LimitedFPS,
 };
 
-pub fn run(cpu: *Arm7tdmi, scheduler: *Scheduler, tracker: *Tracker, sync: Synchro) void {
+pub fn run(cpu: *Arm7tdmi, scheduler: *Scheduler, tracker: *Tracker, sync: *Synchro) void {
     const audio_sync = config.config().guest.audio_sync and !config.config().host.mute;
     if (audio_sync) log.info("Audio sync enabled", .{});
 
@@ -63,7 +76,7 @@ pub fn run(cpu: *Arm7tdmi, scheduler: *Scheduler, tracker: *Tracker, sync: Synch
     }
 }
 
-fn inner(comptime kind: RunKind, audio_sync: bool, cpu: *Arm7tdmi, scheduler: *Scheduler, tracker: ?*Tracker, sync: Synchro) void {
+fn inner(comptime kind: RunKind, audio_sync: bool, cpu: *Arm7tdmi, scheduler: *Scheduler, tracker: ?*Tracker, sync: *Synchro) void {
     if (kind == .UnlimitedFPS or kind == .LimitedFPS) {
         std.debug.assert(tracker != null);
         log.info("FPS tracking enabled", .{});
@@ -71,16 +84,15 @@ fn inner(comptime kind: RunKind, audio_sync: bool, cpu: *Arm7tdmi, scheduler: *S
 
     const bus_ptr: *Bus = @ptrCast(@alignCast(cpu.bus.ptr));
 
+    // FIXME: audioSync accesses emulator state without any guarantees
+
     switch (kind) {
         .Unlimited, .UnlimitedFPS => {
             log.info("Emulation w/out video sync", .{});
 
-            while (!sync.should_quit.load(.Monotonic)) {
-                if (sync.ui_busy.load(.Monotonic) or sync.paused.load(.Monotonic)) {
-                    sync.did_pause.store(true, .Monotonic);
-
-                    continue;
-                }
+            while (!sync.should_quit.load(.monotonic)) {
+                handleChannel(cpu, &sync.ch);
+                if (sync.paused.load(.monotonic)) continue;
 
                 runFrame(scheduler, cpu);
                 audioSync(audio_sync, bus_ptr.apu.stream, &bus_ptr.apu.is_buffer_full);
@@ -93,12 +105,9 @@ fn inner(comptime kind: RunKind, audio_sync: bool, cpu: *Arm7tdmi, scheduler: *S
             var timer = Timer.start() catch @panic("failed to initalize std.timer.Timer");
             var wake_time: u64 = frame_period;
 
-            while (!sync.should_quit.load(.Monotonic)) {
-                if (sync.ui_busy.load(.Monotonic) or sync.paused.load(.Monotonic)) {
-                    sync.did_pause.store(true, .Release);
-
-                    continue;
-                }
+            while (!sync.should_quit.load(.monotonic)) {
+                handleChannel(cpu, &sync.ch);
+                if (sync.paused.load(.monotonic)) continue;
 
                 runFrame(scheduler, cpu);
                 const new_wake_time = videoSync(&timer, wake_time);
@@ -118,6 +127,22 @@ fn inner(comptime kind: RunKind, audio_sync: bool, cpu: *Arm7tdmi, scheduler: *S
     }
 }
 
+inline fn handleChannel(cpu: *Arm7tdmi, channel: *Channel(Synchro.Message)) void {
+    const message = channel.pop() orelse return;
+
+    switch (message) {
+        .rom_path => |path_buf| {
+            const path = std.mem.sliceTo(&path_buf, 0);
+            replaceGamepak(cpu, path) catch |e| log.err("failed to replace GamePak: {}", .{e});
+        },
+        .bios_path => |path_buf| {
+            const path = std.mem.sliceTo(&path_buf, 0);
+            replaceBios(cpu, path) catch |e| log.err("failed to replace BIOS: {}", .{e});
+        },
+        .restart => reset(cpu),
+    }
+}
+
 pub fn runFrame(sched: *Scheduler, cpu: *Arm7tdmi) void {
     const frame_end = sched.tick + cycles_per_frame;
 
@@ -204,6 +229,49 @@ pub const EmuThing = struct {
     const Interface = @import("gdbstub").Emulator;
     const Allocator = std.mem.Allocator;
 
+    pub const target =
+        \\<target version="1.0">
+        \\    <architecture>armv4t</architecture>
+        \\    <feature name="org.gnu.gdb.arm.core">
+        \\        <reg name="r0" bitsize="32" type="uint32"/>
+        \\        <reg name="r1" bitsize="32" type="uint32"/>
+        \\        <reg name="r2" bitsize="32" type="uint32"/>
+        \\        <reg name="r3" bitsize="32" type="uint32"/>
+        \\        <reg name="r4" bitsize="32" type="uint32"/>
+        \\        <reg name="r5" bitsize="32" type="uint32"/>
+        \\        <reg name="r6" bitsize="32" type="uint32"/>
+        \\        <reg name="r7" bitsize="32" type="uint32"/>
+        \\        <reg name="r8" bitsize="32" type="uint32"/>
+        \\        <reg name="r9" bitsize="32" type="uint32"/>
+        \\        <reg name="r10" bitsize="32" type="uint32"/>
+        \\        <reg name="r11" bitsize="32" type="uint32"/>
+        \\        <reg name="r12" bitsize="32" type="uint32"/>
+        \\        <reg name="sp" bitsize="32" type="data_ptr"/>
+        \\        <reg name="lr" bitsize="32"/>
+        \\        <reg name="pc" bitsize="32" type="code_ptr"/>
+        \\
+        \\        <reg name="cpsr" bitsize="32" regnum="25"/>
+        \\    </feature>
+        \\</target>
+    ;
+
+    // Game Pak SRAM isn't included
+    // TODO: Can i be more specific here?
+    pub const map =
+        \\ <memory-map version="1.0">
+        \\     <memory type="rom" start="0x00000000" length="0x00004000"/>
+        \\     <memory type="ram" start="0x02000000" length="0x00040000"/>
+        \\     <memory type="ram" start="0x03000000" length="0x00008000"/>
+        \\     <memory type="ram" start="0x04000000" length="0x00000400"/>
+        \\     <memory type="ram" start="0x05000000" length="0x00000400"/>
+        \\     <memory type="ram" start="0x06000000" length="0x00018000"/>
+        \\     <memory type="ram" start="0x07000000" length="0x00000400"/>
+        \\     <memory type="rom" start="0x08000000" length="0x02000000"/>
+        \\     <memory type="rom" start="0x0A000000" length="0x02000000"/>
+        \\     <memory type="rom" start="0x0C000000" length="0x02000000"/>
+        \\ </memory-map>
+    ;
+
     cpu: *Arm7tdmi,
     scheduler: *Scheduler,
 
@@ -255,21 +323,21 @@ pub const EmuThing = struct {
     }
 };
 
-pub fn reset(cpu: *Arm7tdmi) void {
+fn reset(cpu: *Arm7tdmi) void {
     // @breakpoint();
     cpu.sched.reset(); // Yes this is order sensitive, see the PPU reset for why
     cpu.bus.reset();
     cpu.reset();
 }
 
-pub fn replaceGamepak(cpu: *Arm7tdmi, file_path: []const u8) !void {
+fn replaceGamepak(cpu: *Arm7tdmi, file_path: []const u8) !void {
     const bus_ptr: *Bus = @ptrCast(@alignCast(cpu.bus.ptr));
 
     try bus_ptr.replaceGamepak(file_path);
     reset(cpu);
 }
 
-pub fn replaceBios(cpu: *Arm7tdmi, file_path: []const u8) !void {
+fn replaceBios(cpu: *Arm7tdmi, file_path: []const u8) !void {
     const bus_ptr: *Bus = @ptrCast(@alignCast(cpu.bus.ptr));
 
     const allocator = bus_ptr.bios.allocator;

src/core/ppu/Oam.zig

@@ -12,7 +12,7 @@ pub fn read(self: *const Self, comptime T: type, address: usize) T {
     const addr = address & 0x3FF;
 
     return switch (T) {
-        u32, u16, u8 => std.mem.readIntSliceLittle(T, self.buf[addr..][0..@sizeOf(T)]),
+        u32, u16, u8 => std.mem.readInt(T, self.buf[addr..][0..@sizeOf(T)], .little),
         else => @compileError("OAM: Unsupported read width"),
     };
 }
@@ -21,7 +21,7 @@ pub fn write(self: *Self, comptime T: type, address: usize, value: T) void {
     const addr = address & 0x3FF;
 
     switch (T) {
-        u32, u16 => std.mem.writeIntSliceLittle(T, self.buf[addr..][0..@sizeOf(T)], value),
+        u32, u16 => std.mem.writeInt(T, self.buf[addr..][0..@sizeOf(T)], value, .little),
         u8 => return, // 8-bit writes are explicitly ignored
         else => @compileError("OAM: Unsupported write width"),
     }

src/core/ppu/Palette.zig

@@ -12,7 +12,7 @@ pub fn read(self: *const Self, comptime T: type, address: usize) T {
     const addr = address & 0x3FF;
 
     return switch (T) {
-        u32, u16, u8 => std.mem.readIntSliceLittle(T, self.buf[addr..][0..@sizeOf(T)]),
+        u32, u16, u8 => std.mem.readInt(T, self.buf[addr..][0..@sizeOf(T)], .little),
         else => @compileError("PALRAM: Unsupported read width"),
     };
 }
@@ -21,10 +21,10 @@ pub fn write(self: *Self, comptime T: type, address: usize, value: T) void {
     const addr = address & 0x3FF;
 
     switch (T) {
-        u32, u16 => std.mem.writeIntSliceLittle(T, self.buf[addr..][0..@sizeOf(T)], value),
+        u32, u16 => std.mem.writeInt(T, self.buf[addr..][0..@sizeOf(T)], value, .little),
         u8 => {
             const align_addr = addr & ~@as(u32, 1); // Aligned to Halfword boundary
-            std.mem.writeIntSliceLittle(u16, self.buf[align_addr..][0..@sizeOf(u16)], @as(u16, value) * 0x101);
+            std.mem.writeInt(u16, self.buf[align_addr..][0..@sizeOf(u16)], @as(u16, value) * 0x101, .little);
         },
         else => @compileError("PALRAM: Unsupported write width"),
     }
@@ -47,5 +47,5 @@ pub fn deinit(self: *Self) void {
 }
 
 pub inline fn backdrop(self: *const Self) u16 {
-    return std.mem.readIntNative(u16, self.buf[0..2]);
+    return std.mem.readInt(u16, self.buf[0..2], .little);
 }

src/core/ppu/Vram.zig

@@ -13,7 +13,7 @@ pub fn read(self: *const Self, comptime T: type, address: usize) T {
     const addr = Self.mirror(address);
 
     return switch (T) {
-        u32, u16, u8 => std.mem.readIntSliceLittle(T, self.buf[addr..][0..@sizeOf(T)]),
+        u32, u16, u8 => std.mem.readInt(T, self.buf[addr..][0..@sizeOf(T)], .little),
         else => @compileError("VRAM: Unsupported read width"),
     };
 }
@@ -23,7 +23,7 @@ pub fn write(self: *Self, comptime T: type, dispcnt: io.DisplayControl, address:
     const idx = Self.mirror(address);
 
     switch (T) {
-        u32, u16 => std.mem.writeIntSliceLittle(T, self.buf[idx..][0..@sizeOf(T)], value),
+        u32, u16 => std.mem.writeInt(T, self.buf[idx..][0..@sizeOf(T)], value, .little),
         u8 => {
             // Ignore write if it falls within the boundaries of OBJ VRAM
             switch (mode) {
@@ -32,7 +32,7 @@ pub fn write(self: *Self, comptime T: type, dispcnt: io.DisplayControl, address:
             }
 
             const align_idx = idx & ~@as(u32, 1); // Aligned to a halfword boundary
-            std.mem.writeIntSliceLittle(u16, self.buf[align_idx..][0..@sizeOf(u16)], @as(u16, value) * 0x101);
+            std.mem.writeInt(u16, self.buf[align_idx..][0..@sizeOf(u16)], @as(u16, value) * 0x101, .little);
         },
         else => @compileError("VRAM: Unsupported write width"),
     }

src/imgui.zig

@@ -13,6 +13,7 @@ const Gui = @import("platform.zig").Gui;
 const Arm7tdmi = @import("arm32").Arm7tdmi;
 const Scheduler = @import("core/scheduler.zig").Scheduler;
 const Bus = @import("core/Bus.zig");
+const Synchro = @import("core/emu.zig").Synchro;
 
 const RingBuffer = @import("zba-util").RingBuffer;
 const Dimensions = @import("platform.zig").Dimensions;
@@ -70,11 +71,13 @@ pub const State = struct {
     }
 };
 
-pub fn draw(state: *State, win_dim: Dimensions, tex_id: GLuint, cpu: *Arm7tdmi) bool {
+pub fn draw(state: *State, sync: *Synchro, dim: Dimensions, cpu: *const Arm7tdmi, tex_id: GLuint) bool {
     const scn_scale = config.config().host.win_scale;
     const bus_ptr: *Bus = @ptrCast(@alignCast(cpu.bus.ptr));
 
-    zgui.backend.newFrame(@floatFromInt(win_dim.width), @floatFromInt(win_dim.height));
+    zgui.backend.newFrame(@floatFromInt(dim.width), @floatFromInt(dim.height));
+
+    state.title = handleTitle(&bus_ptr.pak.title);
 
     {
         _ = zgui.beginMainMenuBar();
@@ -87,42 +90,59 @@ pub fn draw(state: *State, win_dim: Dimensions, tex_id: GLuint, cpu: *Arm7tdmi)
                 state.should_quit = true;
 
             if (zgui.menuItem("Insert ROM", .{})) blk: {
-                const maybe_path = nfd.openFileDialog("gba", null) catch |e| {
-                    log.err("failed to open file dialog: {}", .{e});
-                    break :blk;
-                };
+                const file_path = tmp: {
+                    const path_opt = nfd.openFileDialog("gba", null) catch |e| {
+                        log.err("file dialog failed to open: {}", .{e});
+                        break :blk;
+                    };
 
-                const file_path = maybe_path orelse {
-                    log.warn("did not receive a file path", .{});
-                    break :blk;
+                    break :tmp path_opt orelse {
+                        log.warn("did not receive a file path", .{});
+                        break :blk;
+                    };
                 };
                 defer nfd.freePath(file_path);
 
                 log.info("user chose: \"{s}\"", .{file_path});
-                emu.replaceGamepak(cpu, file_path) catch |e| {
-                    log.err("failed to replace GamePak: {}", .{e});
+
+                const message = tmp: {
+                    var msg: Synchro.Message = .{ .rom_path = undefined };
+                    @memcpy(msg.rom_path[0..file_path.len], file_path);
+                    break :tmp msg;
+                };
+
+                sync.ch.push(message) catch |e| {
+                    log.err("failed to send file path to emu thread: {}", .{e});
                     break :blk;
                 };
 
-                state.title = handleTitle(&bus_ptr.pak.title);
                 state.emulation = .{ .Transition = .Active };
             }
 
             if (zgui.menuItem("Load BIOS", .{})) blk: {
-                const maybe_path = nfd.openFileDialog("bin", null) catch |e| {
-                    log.err("failed to open file dialog: {}", .{e});
-                    break :blk;
-                };
+                const file_path = tmp: {
+                    const path_opt = nfd.openFileDialog("bin", null) catch |e| {
+                        log.err("file dialog failed to open: {}", .{e});
+                        break :blk;
+                    };
 
-                const file_path = maybe_path orelse {
-                    log.warn("did not receive a file path", .{});
-                    break :blk;
+                    break :tmp path_opt orelse {
+                        log.warn("did not receive a file path", .{});
+                        break :blk;
+                    };
                 };
                 defer nfd.freePath(file_path);
 
                 log.info("user chose: \"{s}\"", .{file_path});
-                emu.replaceBios(cpu, file_path) catch |e| {
-                    log.err("failed to replace BIOS: {}", .{e});
+
+                const message = tmp: {
+                    var msg: Synchro.Message = .{ .bios_path = undefined };
+                    @memcpy(msg.bios_path[0..file_path.len], file_path);
+                    break :tmp msg;
+                };
+
+                sync.ch.push(message) catch |e| {
+                    log.err("failed to send file path to emu thread: {}", .{e});
                     break :blk;
                 };
             }
@@ -149,7 +169,7 @@ pub fn draw(state: *State, win_dim: Dimensions, tex_id: GLuint, cpu: *Arm7tdmi)
             }
 
             if (zgui.menuItem("Restart", .{}))
-                emu.reset(cpu);
+                sync.ch.push(.restart) catch |e| log.err("failed to send restart req to emu thread: {}", .{e});
         }
 
         if (zgui.beginMenu("Stats", true)) {
@@ -175,7 +195,7 @@ pub fn draw(state: *State, win_dim: Dimensions, tex_id: GLuint, cpu: *Arm7tdmi)
         _ = zgui.begin(window_title, .{ .flags = .{ .no_resize = true, .always_auto_resize = true } });
         defer zgui.end();
 
-        zgui.image(@ptrFromInt(tex_id), .{ .w = w, .h = h, .uv0 = .{ 0, 1 }, .uv1 = .{ 1, 0 } });
+        zgui.image(@ptrFromInt(tex_id), .{ .w = w, .h = h });
     }
 
     // TODO: Any other steps to respect the copyright of the libraries I use?
@@ -324,9 +344,9 @@ pub fn draw(state: *State, win_dim: Dimensions, tex_id: GLuint, cpu: *Arm7tdmi)
         const Event = std.meta.Child(@TypeOf(sched_ptr.queue.items));
 
         var items: [20]Event = undefined;
-        const len = sched_ptr.queue.len;
+        const len = @min(sched_ptr.queue.items.len, items.len);
 
-        @memcpy(&items, sched_ptr.queue.items);
+        @memcpy(items[0..len], sched_ptr.queue.items[0..len]);
         std.mem.sort(Event, items[0..len], {}, widgets.eventDesc(Event));
 
         for (items[0..len]) |event| {
@@ -345,9 +365,9 @@ pub fn draw(state: *State, win_dim: Dimensions, tex_id: GLuint, cpu: *Arm7tdmi)
         widgets.paletteGrid(.Object, cpu);
     }
 
-    {
-        zgui.showDemoWindow(null);
-    }
+    // {
+    //     zgui.showDemoWindow(null);
+    // }
 
     return true; // request redraw
 }

src/main.zig

@@ -61,7 +61,8 @@ pub fn main() void {
     defer allocator.free(config_path);
 
     // Parse CLI
-    const result = clap.parse(clap.Help, &params, clap.parsers.default, .{}) catch |e| exitln("failed to parse cli: {}", .{e});
+
+    const result = clap.parse(clap.Help, &params, clap.parsers.default, .{ .allocator = allocator }) catch |e| exitln("failed to parse cli: {}", .{e});
     defer result.deinit();
 
     // TODO: Move config file to XDG Config directory?
@@ -101,8 +102,8 @@ pub fn main() void {
 
     var bus: Bus = undefined;
 
-    var ischeduler = IScheduler.init(&scheduler);
-    var ibus = IBus.init(&bus);
+    const ischeduler = IScheduler.init(&scheduler);
+    const ibus = IBus.init(&bus);
 
     var cpu = Arm7tdmi.init(ischeduler, ibus);
 
@@ -119,16 +120,8 @@ pub fn main() void {
     var gui = Gui.init(allocator, &bus.apu, title_ptr) catch |e| exitln("failed to init gui: {}", .{e});
     defer gui.deinit();
 
-    var sync: Synchro = blk: {
-        const AtomicBool = std.atomic.Atomic(bool);
-
-        var ui_busy = AtomicBool.init(false);
-        var paused = AtomicBool.init(true);
-        var should_quit = AtomicBool.init(false);
-        var did_pause = AtomicBool.init(false);
-
-        break :blk .{ .ui_busy = &ui_busy, .paused = &paused, .should_quit = &should_quit, .did_pause = &did_pause };
-    };
+    var sync = Synchro.init(allocator) catch |e| exitln("failed to allocate sync types: {}", .{e});
+    defer sync.deinit(allocator);
 
     if (result.args.gdb != 0) {
         const Server = @import("gdbstub").Server;
@@ -140,30 +133,33 @@ pub fn main() void {
 
         log.info("Ready to connect", .{});
 
-        var server = Server.init(emulator) catch |e| exitln("failed to init gdb server: {}", .{e});
+        var server = Server.init(
+            emulator,
+            .{ .memory_map = EmuThing.map, .target = EmuThing.target },
+        ) catch |e| exitln("failed to init gdb server: {}", .{e});
         defer server.deinit(allocator);
 
         log.info("Starting GDB Server Thread", .{});
 
-        const thread = std.Thread.spawn(.{}, Server.run, .{ &server, allocator, sync.should_quit }) catch |e| exitln("gdb server thread crashed: {}", .{e});
+        const thread = std.Thread.spawn(.{}, Server.run, .{ &server, allocator, &sync.should_quit }) catch |e| exitln("gdb server thread crashed: {}", .{e});
         defer thread.join();
 
         gui.run(.{
             .cpu = &cpu,
             .scheduler = &scheduler,
-            .sync = sync,
+            .sync = &sync,
         }) catch |e| exitln("main thread panicked: {}", .{e});
     } else {
         var tracker = FpsTracker.init();
 
-        const thread = std.Thread.spawn(.{}, emu.run, .{ &cpu, &scheduler, &tracker, sync }) catch |e| exitln("emu thread panicked: {}", .{e});
+        const thread = std.Thread.spawn(.{}, emu.run, .{ &cpu, &scheduler, &tracker, &sync }) catch |e| exitln("emu thread panicked: {}", .{e});
         defer thread.join();
 
         gui.run(.{
             .cpu = &cpu,
             .scheduler = &scheduler,
             .tracker = &tracker,
-            .sync = sync,
+            .sync = &sync,
         }) catch |e| exitln("main thread panicked: {}", .{e});
     }
 }
@@ -201,7 +197,7 @@ fn configFilePath(allocator: Allocator, config_path: []const u8) ![]const u8 {
         const config_file = std.fs.createFileAbsolute(path, .{}) catch |err| exitln("failed to create \"{s}\": {}", .{ path, err });
         defer config_file.close();
 
-        try config_file.writeAll(@embedFile("../example.toml"));
+        try config_file.writeAll(@embedFile("example.toml"));
     };
 
     return path;
@@ -234,5 +230,5 @@ fn exitln(comptime format: []const u8, args: anytype) noreturn {
     const stderr = std.io.getStdErr().writer();
     stderr.print(format, args) catch {}; // Just exit already...
     stderr.writeByte('\n') catch {};
-    std.os.exit(1);
+    std.process.exit(1);
 }

src/platform.zig

@@ -95,7 +95,7 @@ pub const Gui = struct {
     }
 
     const RunOptions = struct {
-        sync: Synchro,
+        sync: *Synchro,
         tracker: ?*FpsTracker = null,
         cpu: *Arm7tdmi,
         scheduler: *Scheduler,
@@ -108,18 +108,17 @@ pub const Gui = struct {
 
         const bus_ptr: *Bus = @ptrCast(@alignCast(cpu.bus.ptr));
 
-        const objects = opengl_impl.createObjects();
-        defer gl.deleteBuffers(3, @as(*const [3]GLuint, &.{ objects.vao, objects.vbo, objects.ebo }));
+        const vao_id = opengl_impl.vao();
+        defer gl.deleteVertexArrays(1, &[_]GLuint{vao_id});
 
-        const emu_tex = opengl_impl.createScreenTexture(bus_ptr.ppu.framebuf.get(.Renderer));
-        const out_tex = opengl_impl.createOutputTexture();
+        const emu_tex = opengl_impl.screenTex(bus_ptr.ppu.framebuf.get(.Renderer));
+        const out_tex = opengl_impl.outTex();
         defer gl.deleteTextures(2, &[_]GLuint{ emu_tex, out_tex });
 
-        const fbo_id = try opengl_impl.createFrameBuffer(out_tex);
+        const fbo_id = try opengl_impl.frameBuffer(out_tex);
         defer gl.deleteFramebuffers(1, &fbo_id);
 
-        // TODO: Support dynamically switching shaders?
-        const prog_id = try opengl_impl.compileShaders();
+        const prog_id = try opengl_impl.program(); // Dynamic Shaders?
         defer gl.deleteProgram(prog_id);
 
         var win_dim: Dimensions = default_dim;
@@ -127,7 +126,7 @@ pub const Gui = struct {
         emu_loop: while (true) {
             // Outside of `SDL.SDL_QUIT` below, the DearImgui UI might signal that the program
             // should exit, in which case we should also handle this
-            if (self.state.should_quit) break :emu_loop;
+            if (self.state.should_quit or sync.should_quit.load(.monotonic)) break :emu_loop;
 
             var event: SDL.SDL_Event = undefined;
             while (SDL.SDL_PollEvent(&event) != 0) {
@@ -154,7 +153,7 @@ pub const Gui = struct {
                             else => {},
                         }
 
-                        bus_ptr.io.keyinput.fetchAnd(~keyinput.raw, .Monotonic);
+                        bus_ptr.io.keyinput.fetchAnd(~keyinput.raw, .monotonic);
                     },
                     SDL.SDL_KEYUP => {
                         // TODO: Make use of compare_and_xor?
@@ -175,7 +174,7 @@ pub const Gui = struct {
                             else => {},
                         }
 
-                        bus_ptr.io.keyinput.fetchOr(keyinput.raw, .Monotonic);
+                        bus_ptr.io.keyinput.fetchOr(keyinput.raw, .monotonic);
                     },
                     SDL.SDL_WINDOWEVENT => {
                         if (event.window.event == SDL.SDL_WINDOWEVENT_RESIZED) {
@@ -194,7 +193,7 @@ pub const Gui = struct {
             switch (self.state.emulation) {
                 .Transition => |inner| switch (inner) {
                     .Active => {
-                        sync.paused.store(false, .Monotonic);
+                        sync.paused.store(false, .monotonic);
                         if (!config.config().host.mute) SDL.SDL_PauseAudioDevice(self.audio.device, 0);
 
                         self.state.emulation = .Active;
@@ -202,27 +201,12 @@ pub const Gui = struct {
                     .Inactive => {
                         // Assert that double pausing is impossible
                         SDL.SDL_PauseAudioDevice(self.audio.device, 1);
-                        sync.paused.store(true, .Monotonic);
+                        sync.paused.store(true, .monotonic);
 
                         self.state.emulation = .Inactive;
                     },
                 },
-                .Active => blk: {
-                    sync.ui_busy.store(true, .Monotonic);
-                    defer sync.ui_busy.store(false, .Monotonic);
-
-                    // spin until we know the emu is paused :)
-
-                    const timeout = 0x100000;
-                    wait_loop: for (0..timeout) |i| {
-                        const ret = sync.did_pause.compareAndSwap(true, false, .Acquire, .Monotonic);
-                        if (ret == null) break :wait_loop;
-
-                        if (i == timeout - 1) break :blk;
-                    }
-
-                    // while (sync.did_pause.compareAndSwap(true, false, .Acquire, .Acquire) != null) std.atomic.spinLoopHint();
-
+                .Active => {
                     // Add FPS count to the histogram
                     if (tracker) |t| self.state.fps_hist.push(t.value()) catch {};
 
@@ -231,9 +215,8 @@ pub const Gui = struct {
                         gl.bindFramebuffer(gl.FRAMEBUFFER, fbo_id);
                         defer gl.bindFramebuffer(gl.FRAMEBUFFER, 0);
 
-                        const buf = bus_ptr.ppu.framebuf.get(.Renderer);
                         gl.viewport(0, 0, gba_width, gba_height);
-                        opengl_impl.drawScreenTexture(emu_tex, prog_id, objects, buf);
+                        opengl_impl.drawScreen(emu_tex, prog_id, vao_id, bus_ptr.ppu.framebuf.get(.Renderer));
                     }
 
                     // FIXME: We only really care about locking the audio device (and therefore writing silence)
@@ -242,9 +225,9 @@ pub const Gui = struct {
                     SDL.SDL_LockAudioDevice(self.audio.device);
                     defer SDL.SDL_UnlockAudioDevice(self.audio.device);
 
-                    zgui_redraw = imgui.draw(&self.state, win_dim, out_tex, cpu);
+                    zgui_redraw = imgui.draw(&self.state, sync, win_dim, cpu, out_tex);
                 },
-                .Inactive => zgui_redraw = imgui.draw(&self.state, win_dim, out_tex, cpu),
+                .Inactive => zgui_redraw = imgui.draw(&self.state, sync, win_dim, cpu, out_tex),
             }
 
             if (zgui_redraw) {
@@ -260,7 +243,7 @@ pub const Gui = struct {
             SDL.SDL_GL_SwapWindow(self.window);
         }
 
-        sync.should_quit.store(true, .Monotonic);
+        sync.should_quit.store(true, .monotonic);
     }
 
     fn glGetProcAddress(ctx: SDL.SDL_GLContext, proc: [:0]const u8) ?*anyopaque {
@@ -312,44 +295,24 @@ fn panic() noreturn {
 }
 
 const opengl_impl = struct {
-    // zig fmt: off
-    const vertices: [32]f32 = [_]f32{
-        // Positions        // Colours      // Texture Coords
-         1.0, -1.0, 0.0,    1.0, 0.0, 0.0,  1.0, 1.0, // Top Right
-         1.0,  1.0, 0.0,    0.0, 1.0, 0.0,  1.0, 0.0, // Bottom Right
-        -1.0,  1.0, 0.0,    0.0, 0.0, 1.0,  0.0, 0.0, // Bottom Left
-        -1.0, -1.0, 0.0,    1.0, 1.0, 0.0,  0.0, 1.0, // Top Left
-    };
-
-    const indices: [6]u32 = [_]u32{
-        0, 1, 3, // First Triangle
-        1, 2, 3, // Second Triangle
-    };
-    // zig fmt: on
-
-    const Objects = struct { vao: GLuint, vbo: GLuint, ebo: GLuint };
-
-    fn drawScreenTexture(tex_id: GLuint, prog_id: GLuint, ids: Objects, buf: []const u8) void {
+    fn drawScreen(tex_id: GLuint, prog_id: GLuint, vao_id: GLuint, buf: []const u8) void {
         gl.bindTexture(gl.TEXTURE_2D, tex_id);
         defer gl.bindTexture(gl.TEXTURE_2D, 0);
 
         gl.texSubImage2D(gl.TEXTURE_2D, 0, 0, 0, gba_width, gba_height, gl.RGBA, gl.UNSIGNED_INT_8_8_8_8, buf.ptr);
 
-        // Bind VAO, EBO. VBO not bound
-        gl.bindVertexArray(ids.vao); // VAO
+        // Bind VAO
+        gl.bindVertexArray(vao_id);
         defer gl.bindVertexArray(0);
 
-        gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, ids.ebo); // EBO
-        defer gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, 0);
-
         // Use compiled frag + vertex shader
         gl.useProgram(prog_id);
         defer gl.useProgram(0);
 
-        gl.drawElements(gl.TRIANGLES, 6, gl.UNSIGNED_INT, null);
+        gl.drawArrays(gl.TRIANGLE_STRIP, 0, 3);
     }
 
-    fn compileShaders() !GLuint {
+    fn program() !GLuint {
         const vert_shader = @embedFile("shader/pixelbuf.vert");
         const frag_shader = @embedFile("shader/pixelbuf.frag");
 
@@ -369,50 +332,22 @@ const opengl_impl = struct {
 
         if (!shader.didCompile(fs)) return error.FragmentCompileError;
 
-        const program = gl.createProgram();
-        gl.attachShader(program, vs);
-        gl.attachShader(program, fs);
-        gl.linkProgram(program);
+        const prog = gl.createProgram();
+        gl.attachShader(prog, vs);
+        gl.attachShader(prog, fs);
+        gl.linkProgram(prog);
 
-        return program;
+        return prog;
     }
 
-    // Returns the VAO ID since it's used in run()
-    fn createObjects() Objects {
+    fn vao() GLuint {
         var vao_id: GLuint = undefined;
-        var vbo_id: GLuint = undefined;
-        var ebo_id: GLuint = undefined;
-
         gl.genVertexArrays(1, &vao_id);
-        gl.genBuffers(1, &vbo_id);
-        gl.genBuffers(1, &ebo_id);
 
-        gl.bindVertexArray(vao_id);
-        defer gl.bindVertexArray(0);
-
-        gl.bindBuffer(gl.ARRAY_BUFFER, vbo_id);
-        defer gl.bindBuffer(gl.ARRAY_BUFFER, 0);
-
-        gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, ebo_id);
-        defer gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, 0);
-
-        gl.bufferData(gl.ARRAY_BUFFER, @sizeOf(@TypeOf(vertices)), &vertices, gl.STATIC_DRAW);
-        gl.bufferData(gl.ELEMENT_ARRAY_BUFFER, @sizeOf(@TypeOf(indices)), &indices, gl.STATIC_DRAW);
-
-        // Position
-        gl.vertexAttribPointer(0, 3, gl.FLOAT, gl.FALSE, 8 * @sizeOf(f32), null); // lmao
-        gl.enableVertexAttribArray(0);
-        // Colour
-        gl.vertexAttribPointer(1, 3, gl.FLOAT, gl.FALSE, 8 * @sizeOf(f32), @ptrFromInt((3 * @sizeOf(f32))));
-        gl.enableVertexAttribArray(1);
-        // Texture Coord
-        gl.vertexAttribPointer(2, 2, gl.FLOAT, gl.FALSE, 8 * @sizeOf(f32), @ptrFromInt((6 * @sizeOf(f32))));
-        gl.enableVertexAttribArray(2);
-
-        return .{ .vao = vao_id, .vbo = vbo_id, .ebo = ebo_id };
+        return vao_id;
     }
 
-    fn createScreenTexture(buf: []const u8) GLuint {
+    fn screenTex(buf: []const u8) GLuint {
         var tex_id: GLuint = undefined;
         gl.genTextures(1, &tex_id);
 
@@ -427,7 +362,7 @@ const opengl_impl = struct {
         return tex_id;
     }
 
-    fn createOutputTexture() GLuint {
+    fn outTex() GLuint {
         var tex_id: GLuint = undefined;
         gl.genTextures(1, &tex_id);
 
@@ -442,7 +377,7 @@ const opengl_impl = struct {
         return tex_id;
     }
 
-    fn createFrameBuffer(tex_id: GLuint) !GLuint {
+    fn frameBuffer(tex_id: GLuint) !GLuint {
         var fbo_id: GLuint = undefined;
         gl.genFramebuffers(1, &fbo_id);
 
@@ -450,9 +385,7 @@ const opengl_impl = struct {
         defer gl.bindFramebuffer(gl.FRAMEBUFFER, 0);
 
         gl.framebufferTexture(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, tex_id, 0);
-
-        const draw_buffers: [1]GLuint = .{gl.COLOR_ATTACHMENT0};
-        gl.drawBuffers(1, &draw_buffers);
+        gl.drawBuffers(1, &@as(GLuint, gl.COLOR_ATTACHMENT0));
 
         if (gl.checkFramebufferStatus(gl.FRAMEBUFFER) != gl.FRAMEBUFFER_COMPLETE)
             return error.FrameBufferObejctInitFailed;
@@ -461,8 +394,7 @@ const opengl_impl = struct {
     }
 
     const shader = struct {
-        const Kind = enum { vertex, fragment };
-        const log = std.log.scoped(.Shader);
+        const log = std.log.scoped(.shader);
 
         fn didCompile(id: gl.GLuint) bool {
             var success: gl.GLint = undefined;

src/shader/pixelbuf.frag

@@ -1,7 +1,6 @@
 #version 330 core
 out vec4 frag_color;
 
-in vec3 color;
 in vec2 uv;
 
 uniform sampler2D screen;

src/shader/pixelbuf.vert

@@ -1,13 +1,10 @@
 #version 330 core
-layout (location = 0) in vec3 pos;
-layout (location = 1) in vec3 in_color;
-layout (location = 2) in vec2 in_uv;
-
-out vec3 color;
 out vec2 uv;
 
+const vec2 pos[3] = vec2[3](vec2(-1.0f, -1.0f), vec2(-1.0f, 3.0f), vec2(3.0f, -1.0f));
+const vec2 uvs[3] = vec2[3](vec2( 0.0f,  0.0f), vec2( 0.0f, 2.0f), vec2(2.0f,  0.0f));
+
 void main() {
-	color = in_color;
-	uv = in_uv;
-	gl_Position = vec4(pos, 1.0);
-}
+	uv = uvs[gl_VertexID];
+	gl_Position = vec4(pos[gl_VertexID], 0.0, 1.0);
+}

src/util.zig

@@ -11,24 +11,24 @@ pub const FpsTracker = struct {
     const Self = @This();
 
     fps: u32,
-    count: std.atomic.Atomic(u32),
+    count: std.atomic.Value(u32),
     timer: std.time.Timer,
 
     pub fn init() Self {
         return .{
             .fps = 0,
-            .count = std.atomic.Atomic(u32).init(0),
+            .count = std.atomic.Value(u32).init(0),
             .timer = std.time.Timer.start() catch unreachable,
         };
     }
 
     pub fn tick(self: *Self) void {
-        _ = self.count.fetchAdd(1, .Monotonic);
+        _ = self.count.fetchAdd(1, .monotonic);
     }
 
     pub fn value(self: *Self) u32 {
         if (self.timer.read() >= std.time.ns_per_s) {
-            self.fps = self.count.swap(0, .Monotonic);
+            self.fps = self.count.swap(0, .monotonic);
             self.timer.reset();
         }
 
@@ -295,3 +295,31 @@ pub const FrameBuffer = struct {
         return self.layers[if (dev == .Emulator) self.current else ~self.current];
     }
 };
+
+const RingBuffer = @import("zba-util").RingBuffer;
+
+// TODO: Lock Free Queue?
+pub fn Queue(comptime T: type) type {
+    return struct {
+        inner: RingBuffer(T),
+        mtx: std.Thread.Mutex = .{},
+
+        pub fn init(buf: []T) @This() {
+            return .{ .inner = RingBuffer(T).init(buf) };
+        }
+
+        pub fn push(self: *@This(), value: T) !void {
+            self.mtx.lock();
+            defer self.mtx.unlock();
+
+            try self.inner.push(value);
+        }
+
+        pub fn pop(self: *@This()) ?T {
+            self.mtx.lock();
+            defer self.mtx.unlock();
+
+            return self.inner.pop();
+        }
+    };
+}