zba/src/platform.zig
paoda bd02f625a5 feat: upgrade to zig v0.15.1
note: emu crashes for unknown reason
2025-10-12 21:03:32 -05:00

407 lines
15 KiB
Zig

const std = @import("std");
const gl = @import("gl");
const zgui = @import("zgui");
const c = @import("lib.zig").c;
const emu = @import("core/emu.zig");
const config = @import("config.zig");
const imgui = @import("imgui.zig");
const Apu = @import("core/apu.zig").Apu;
const Arm7tdmi = @import("arm32").Arm7tdmi;
const Bus = @import("core/Bus.zig");
const Scheduler = @import("core/scheduler.zig").Scheduler;
const FpsTracker = @import("util.zig").FpsTracker;
const Synchro = @import("core/emu.zig").Synchro;
const KeyInput = @import("core/bus/io.zig").KeyInput;
const gba_width = @import("core/ppu.zig").width;
const gba_height = @import("core/ppu.zig").height;
const GLsizei = gl.sizei;
const SDL_GLContext = *c.SDL_GLContextState;
const Allocator = std.mem.Allocator;
pub const Dimensions = struct { width: u32, height: u32 };
const default_dim: Dimensions = .{ .width = 1280, .height = 720 };
pub const sample_rate = 1 << 15;
// pub const sample_format = SDL.AUDIO_U16;
const window_title = "ZBA";
const errify = @import("lib.zig").errify;
var gl_procs: gl.ProcTable = undefined;
pub const Gui = struct {
const Self = @This();
const log = std.log.scoped(.Gui);
window: *c.SDL_Window,
ctx: SDL_GLContext,
audio: Audio,
state: imgui.State,
allocator: Allocator,
pub fn init(allocator: Allocator, apu: *Apu, title_opt: ?*const [12]u8) !Self {
c.SDL_SetMainReady();
try errify(c.SDL_Init(c.SDL_INIT_VIDEO | c.SDL_INIT_AUDIO | c.SDL_INIT_EVENTS));
try errify(c.SDL_SetAppMetadata(window_title, "0.1.0", "moe.paoda.zba"));
try errify(c.SDL_GL_SetAttribute(c.SDL_GL_CONTEXT_MAJOR_VERSION, gl.info.version_major));
try errify(c.SDL_GL_SetAttribute(c.SDL_GL_CONTEXT_MINOR_VERSION, gl.info.version_minor));
try errify(c.SDL_GL_SetAttribute(c.SDL_GL_CONTEXT_PROFILE_MASK, c.SDL_GL_CONTEXT_PROFILE_CORE));
try errify(c.SDL_GL_SetAttribute(c.SDL_GL_CONTEXT_FLAGS, c.SDL_GL_CONTEXT_FORWARD_COMPATIBLE_FLAG));
const window: *c.SDL_Window = try errify(c.SDL_CreateWindow(window_title, default_dim.width, default_dim.height, c.SDL_WINDOW_OPENGL | c.SDL_WINDOW_RESIZABLE));
errdefer c.SDL_DestroyWindow(window);
const gl_ctx = try errify(c.SDL_GL_CreateContext(window));
errdefer errify(c.SDL_GL_DestroyContext(gl_ctx)) catch {};
try errify(c.SDL_GL_MakeCurrent(window, gl_ctx));
errdefer errify(c.SDL_GL_MakeCurrent(window, null)) catch {};
if (!gl_procs.init(c.SDL_GL_GetProcAddress)) return error.gl_init_failed;
gl.makeProcTableCurrent(&gl_procs);
errdefer gl.makeProcTableCurrent(null);
try errify(c.SDL_GL_SetSwapInterval(@intFromBool(config.config().host.vsync)));
zgui.init(allocator);
zgui.plot.init();
zgui.backend.init(window, gl_ctx);
// zgui.io.setIniFilename(null);
return Self{
.window = window,
.ctx = gl_ctx,
.audio = try Audio.init(apu),
.allocator = allocator,
.state = try imgui.State.init(allocator, title_opt),
};
}
pub fn deinit(self: *Self) void {
self.audio.deinit();
self.state.deinit(self.allocator);
zgui.backend.deinit();
zgui.plot.deinit();
zgui.deinit();
errify(c.SDL_GL_DestroyContext(self.ctx)) catch {};
c.SDL_DestroyWindow(self.window);
c.SDL_Quit();
self.* = undefined;
}
const RunOptions = struct {
sync: *Synchro,
tracker: ?*FpsTracker = null,
cpu: *Arm7tdmi,
scheduler: *Scheduler,
};
pub fn run(self: *Self, opt: RunOptions) !void {
const cpu = opt.cpu;
const tracker = opt.tracker;
const sync = opt.sync;
const bus_ptr: *Bus = @ptrCast(@alignCast(cpu.bus.ptr));
const vao_id = opengl_impl.vao();
defer gl.DeleteVertexArrays(1, vao_id[0..]);
const emu_tex = opengl_impl.screenTex(bus_ptr.ppu.framebuf.get(.Renderer));
defer gl.DeleteTextures(1, emu_tex[0..]);
const out_tex = opengl_impl.outTex();
defer gl.DeleteTextures(1, out_tex[0..]);
const fbo_id = try opengl_impl.frameBuffer(out_tex[0]);
defer gl.DeleteFramebuffers(1, fbo_id[0..]);
const prog_id = try opengl_impl.program(); // Dynamic Shaders?
defer gl.DeleteProgram(prog_id);
var win_dim: Dimensions = default_dim;
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 or sync.should_quit.load(.monotonic)) break :emu_loop;
var event: c.SDL_Event = undefined;
while (c.SDL_PollEvent(&event)) {
_ = zgui.backend.processEvent(&event);
switch (event.type) {
c.SDL_EVENT_QUIT => break :emu_loop,
c.SDL_EVENT_KEY_DOWN => {
// TODO: Make use of compare_and_xor?
var keyinput: KeyInput = .{ .raw = 0x0000 };
switch (event.key.scancode) {
c.SDL_SCANCODE_UP => keyinput.up.write(true),
c.SDL_SCANCODE_DOWN => keyinput.down.write(true),
c.SDL_SCANCODE_LEFT => keyinput.left.write(true),
c.SDL_SCANCODE_RIGHT => keyinput.right.write(true),
c.SDL_SCANCODE_X => keyinput.a.write(true),
c.SDL_SCANCODE_Z => keyinput.b.write(true),
c.SDL_SCANCODE_A => keyinput.shoulder_l.write(true),
c.SDL_SCANCODE_S => keyinput.shoulder_r.write(true),
c.SDL_SCANCODE_RETURN => keyinput.start.write(true),
c.SDL_SCANCODE_RSHIFT => keyinput.select.write(true),
else => {},
}
bus_ptr.io.keyinput.fetchAnd(~keyinput.raw, .monotonic);
},
c.SDL_EVENT_KEY_UP => {
// FIXME(paoda): merge with above?
// TODO: Make use of compare_and_xor?
var keyinput: KeyInput = .{ .raw = 0x0000 };
switch (event.key.scancode) {
c.SDL_SCANCODE_UP => keyinput.up.write(true),
c.SDL_SCANCODE_DOWN => keyinput.down.write(true),
c.SDL_SCANCODE_LEFT => keyinput.left.write(true),
c.SDL_SCANCODE_RIGHT => keyinput.right.write(true),
c.SDL_SCANCODE_X => keyinput.a.write(true),
c.SDL_SCANCODE_Z => keyinput.b.write(true),
c.SDL_SCANCODE_A => keyinput.shoulder_l.write(true),
c.SDL_SCANCODE_S => keyinput.shoulder_r.write(true),
c.SDL_SCANCODE_RETURN => keyinput.start.write(true),
c.SDL_SCANCODE_RSHIFT => keyinput.select.write(true),
else => {},
}
bus_ptr.io.keyinput.fetchOr(keyinput.raw, .monotonic);
},
c.SDL_EVENT_WINDOW_RESIZED => {
log.debug("window resized to: {}x{}", .{ event.window.data1, event.window.data2 });
win_dim.width = @intCast(event.window.data1);
win_dim.height = @intCast(event.window.data2);
},
else => {},
}
}
var zgui_redraw: bool = false;
switch (self.state.emulation) {
.Transition => |inner| switch (inner) {
.Active => {
sync.paused.store(false, .monotonic);
if (!config.config().host.mute) try errify(c.SDL_PauseAudioDevice(c.SDL_AUDIO_DEVICE_DEFAULT_PLAYBACK));
self.state.emulation = .Active;
},
.Inactive => {
// Assert that double pausing is impossible
try errify(c.SDL_ResumeAudioDevice(c.SDL_AUDIO_DEVICE_DEFAULT_PLAYBACK));
sync.paused.store(true, .monotonic);
self.state.emulation = .Inactive;
},
},
.Active => {
// Add FPS count to the histogram
if (tracker) |t| self.state.fps_hist.push(t.value()) catch {};
// Draw GBA Screen to Texture
{
gl.BindFramebuffer(gl.FRAMEBUFFER, fbo_id[0]);
defer gl.BindFramebuffer(gl.FRAMEBUFFER, 0);
gl.Viewport(0, 0, gba_width, gba_height);
opengl_impl.drawScreen(emu_tex[0], prog_id, vao_id[0], bus_ptr.ppu.framebuf.get(.Renderer));
}
// FIXME: We only really care about locking the audio device (and therefore writing silence)
// since if nfd-zig is used the emu may be paused for way too long. Perhaps we should try and limit
// spurious calls to SDL_LockAudioDevice?
try errify(c.SDL_LockAudioStream(self.audio.stream));
defer errify(c.SDL_UnlockAudioStream(self.audio.stream)) catch @panic("TODO: FIXME");
zgui_redraw = imgui.draw(&self.state, sync, win_dim, cpu, out_tex[0]);
},
.Inactive => zgui_redraw = imgui.draw(&self.state, sync, win_dim, cpu, out_tex[0]),
}
if (zgui_redraw) {
// Background Colour
const size = zgui.io.getDisplaySize();
gl.Viewport(0, 0, @intFromFloat(size[0]), @intFromFloat(size[1]));
gl.ClearColor(0, 0, 0, 1.0);
gl.Clear(gl.COLOR_BUFFER_BIT);
zgui.backend.draw();
}
try errify(c.SDL_GL_SwapWindow(self.window));
}
sync.should_quit.store(true, .monotonic);
}
};
const Audio = struct {
const Self = @This();
const log = std.log.scoped(.PlatformAudio);
stream: *c.SDL_AudioStream,
fn init(apu: *Apu) !Self {
var desired: c.SDL_AudioSpec = std.mem.zeroes(c.SDL_AudioSpec);
desired.freq = sample_rate;
desired.format = c.SDL_AUDIO_S16LE;
desired.channels = 2;
log.info("Host Sample Rate: {}Hz, Host Format: SDL_AUDIO_S16LE", .{sample_rate});
const stream = try errify(c.SDL_OpenAudioDeviceStream(c.SDL_AUDIO_DEVICE_DEFAULT_PLAYBACK, &desired, null, null));
errdefer c.SDL_DestroyAudioStream(stream);
apu.stream = stream;
return .{ .stream = stream };
}
fn deinit(self: *Self) void {
c.SDL_DestroyAudioStream(self.stream);
self.* = undefined;
}
};
const opengl_impl = struct {
fn drawScreen(tex_id: gl.uint, prog_id: gl.uint, vao_id: gl.uint, 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
gl.BindVertexArray(vao_id);
defer gl.BindVertexArray(0);
// Use compiled frag + vertex shader
gl.UseProgram(prog_id);
defer gl.UseProgram(0);
gl.DrawArrays(gl.TRIANGLE_STRIP, 0, 3);
}
fn program() !gl.uint {
const vert_shader: [1][*]const u8 = .{@embedFile("shader/pixelbuf.vert")};
const frag_shader: [1][*]const u8 = .{@embedFile("shader/pixelbuf.frag")};
const vs = gl.CreateShader(gl.VERTEX_SHADER);
defer gl.DeleteShader(vs);
gl.ShaderSource(vs, 1, vert_shader[0..], null);
gl.CompileShader(vs);
if (!shader.didCompile(vs)) return error.VertexCompileError;
const fs = gl.CreateShader(gl.FRAGMENT_SHADER);
defer gl.DeleteShader(fs);
gl.ShaderSource(fs, 1, frag_shader[0..], null);
gl.CompileShader(fs);
if (!shader.didCompile(fs)) return error.FragmentCompileError;
const prog = gl.CreateProgram();
gl.AttachShader(prog, vs);
gl.AttachShader(prog, fs);
gl.LinkProgram(prog);
return prog;
}
fn vao() [1]gl.uint {
var vao_id: [1]gl.uint = undefined;
gl.GenVertexArrays(1, vao_id[0..]);
return vao_id;
}
fn screenTex(buf: []const u8) [1]gl.uint {
var tex_id: [1]gl.uint = undefined;
gl.GenTextures(1, tex_id[0..]);
gl.BindTexture(gl.TEXTURE_2D, tex_id[0]);
defer gl.BindTexture(gl.TEXTURE_2D, 0);
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST);
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST);
gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gba_width, gba_height, 0, gl.RGBA, gl.UNSIGNED_INT_8_8_8_8, buf.ptr);
return tex_id;
}
fn outTex() [1]gl.uint {
var tex_id: [1]gl.uint = undefined;
gl.GenTextures(1, tex_id[0..]);
gl.BindTexture(gl.TEXTURE_2D, tex_id[0]);
defer gl.BindTexture(gl.TEXTURE_2D, 0);
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST);
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST);
gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gba_width, gba_height, 0, gl.RGBA, gl.UNSIGNED_INT_8_8_8_8, null);
return tex_id;
}
fn frameBuffer(tex_id: gl.uint) ![1]gl.uint {
var fbo_id: [1]gl.uint = undefined;
gl.GenFramebuffers(1, fbo_id[0..]);
gl.BindFramebuffer(gl.FRAMEBUFFER, fbo_id[0]);
defer gl.BindFramebuffer(gl.FRAMEBUFFER, 0);
gl.FramebufferTexture(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, tex_id, 0);
gl.DrawBuffers(1, &.{gl.COLOR_ATTACHMENT0});
if (gl.CheckFramebufferStatus(gl.FRAMEBUFFER) != gl.FRAMEBUFFER_COMPLETE)
return error.FrameBufferObejctInitFailed;
return fbo_id;
}
const shader = struct {
const log = std.log.scoped(.shader);
fn didCompile(id: gl.uint) bool {
var success: [1]gl.int = undefined;
gl.GetShaderiv(id, gl.COMPILE_STATUS, success[0..]);
if (success[0] == 0) err(id);
return success[0] == 1;
}
fn err(id: gl.uint) void {
const buf_len = 512;
var error_msg: [buf_len]u8 = undefined;
gl.GetShaderInfoLog(id, buf_len, null, &error_msg);
log.err("{s}", .{std.mem.sliceTo(&error_msg, 0)});
}
};
};