Refactor "backend" concept

See plat/sdl2


Former-commit-id: 5f7c9625467003d5b73307959095eb5365db523e

Cargo.toml

@@ -25,6 +25,10 @@ zip = "0.5.3"
 ctrlc = "3.1.3"
 cpal="0.10.0"
 
+[[bin]]
+name = "rba-sdl2"
+path = "src/plat/sdl2/main.rs"
+
 [profile.dev]
 opt-level = 0
 debug = true

src/bin/main.rs

@@ -1,79 +0,0 @@
-use std::ffi::OsStr;
-use std::time;
-
-#[macro_use]
-extern crate clap;
-
-use clap::{App, ArgMatches};
-
-extern crate rustboyadvance_ng;
-
-use rustboyadvance_ng::backend::*;
-use rustboyadvance_ng::core::arm7tdmi::Core;
-use rustboyadvance_ng::core::cartridge::Cartridge;
-use rustboyadvance_ng::core::{GBAError, GBAResult, GameBoyAdvance};
-use rustboyadvance_ng::debugger::Debugger;
-use rustboyadvance_ng::util::read_bin_file;
-
-fn run_emulator(matches: &ArgMatches) -> GBAResult<()> {
-    let skip_bios = matches.occurrences_of("skip_bios") != 0;
-    let no_framerate_limit = matches.occurrences_of("no_framerate_limit") != 0;
-    let debug = matches.occurrences_of("debug") != 0;
-
-    let backend: Box<EmulatorBackend> = match matches.value_of("backend") {
-        Some("sdl2") => Box::new(Sdl2Backend::new()),
-        Some("minifb") => Box::new(MinifbBackend::new()),
-        // None => DummyBackend::new(),
-        None => Box::new(DummyBackend::new()),
-        _ => unreachable!(),
-    };
-
-    let bios_bin = read_bin_file(matches.value_of("bios").unwrap_or_default())?;
-
-    let cart = Cartridge::from_path(matches.value_of("game_rom").unwrap())?;
-    println!("loaded rom: {:#?}", cart.header);
-
-    let mut core = Core::new();
-    if skip_bios {
-        core.skip_bios();
-    }
-
-    let mut gba = GameBoyAdvance::new(core, bios_bin, cart, backend);
-
-    if debug {
-        gba.cpu.set_verbose(true);
-        let mut debugger = Debugger::new(gba);
-        println!("starting debugger...");
-        debugger.repl(matches.value_of("script_file"))?;
-        println!("ending debugger...");
-    } else {
-        let frame_time = time::Duration::new(0, 1_000_000_000u32 / 60);
-        loop {
-            let start_time = time::Instant::now();
-            gba.frame();
-            if !no_framerate_limit {
-                let time_passed = start_time.elapsed();
-                let delay = frame_time.checked_sub(time_passed);
-                match delay {
-                    None => {}
-                    Some(delay) => {
-                        ::std::thread::sleep(delay);
-                    }
-                };
-            }
-        }
-    }
-
-    Ok(())
-}
-
-fn main() {
-    let yaml = load_yaml!("cli.yml");
-    let matches = App::from_yaml(yaml).get_matches();
-
-    let result = run_emulator(&matches);
-
-    if let Err(err) = result {
-        println!("Got an error: {:?}", err);
-    }
-}

src/core/cartridge.rs

@@ -1,3 +1,4 @@
+use std::ffi::OsStr;
 use std::fs::File;
 use std::io::prelude::*;
 use std::path::Path;
@@ -8,7 +9,7 @@ use zip::ZipArchive;
 
 use super::super::util::read_bin_file;
 use super::arm7tdmi::{bus::Bus, Addr};
-use super::GBAResult;
+use super::{GBAError, GBAResult};
 
 /// From GBATEK
 ///
@@ -75,30 +76,40 @@ pub struct Cartridge {
     bytes: Box<[u8]>,
 }
 
-fn load_rom(path: &str) -> GBAResult<Vec<u8>> {
+fn load_rom(path: &Path) -> GBAResult<Vec<u8>> {
-    if path.ends_with(".zip") {
+    match path.extension() {
-        let zipfile = File::open(path)?;
+        Some(extension) => match extension.to_str() {
-        let mut archive = ZipArchive::new(zipfile)?;
+            Some("zip") => {
-        for i in 0..archive.len() {
+                let zipfile = File::open(path)?;
-            let mut file = archive.by_index(i)?;
+                let mut archive = ZipArchive::new(zipfile)?;
-            if file.name().ends_with(".gba") {
+                for i in 0..archive.len() {
-                let mut buf = Vec::new();
+                    let mut file = archive.by_index(i)?;
-                file.read_to_end(&mut buf)?;
+                    if file.name().ends_with(".gba") {
+                        let mut buf = Vec::new();
+                        file.read_to_end(&mut buf)?;
+                        return Ok(buf);
+                    }
+                }
+                panic!("no .gba file contained in the zip file");
+            }
+            _ => {
+                let buf = read_bin_file(path)?;
                 return Ok(buf);
             }
+        },
+        _ => {
+            let buf = read_bin_file(path)?;
+            return Ok(buf);
         }
-        panic!("no .gba file contained in the zip file");
-    } else {
-        let buf = read_bin_file(path)?;
-        Ok(buf)
     }
 }
 
 impl Cartridge {
     const MIN_SIZE: usize = 4 * 1024 * 1024;
 
-    pub fn from_path(rom_path: &str) -> GBAResult<Cartridge> {
+    pub fn from_path(rom_path: &Path) -> GBAResult<Cartridge> {
         let mut rom_bin = load_rom(rom_path)?;
+        println!("loaded {} bytes", rom_bin.len());
 
         if rom_bin.len() < Cartridge::MIN_SIZE {
             rom_bin.resize_with(Cartridge::MIN_SIZE, Default::default);

src/core/gba.rs

@@ -7,45 +7,34 @@ use super::iodev::*;
 use super::sysbus::SysBus;
 
 use super::SyncedIoDevice;
-use crate::backend::*;
+
+use super::super::{AudioInterface, InputInterface, VideoInterface};
 
 pub struct GameBoyAdvance {
-    backend: Box<dyn EmulatorBackend>,
     pub cpu: Core,
     pub sysbus: Box<SysBus>,
 }
 
 impl GameBoyAdvance {
-    pub fn new(
+    pub fn new(cpu: Core, bios_rom: Vec<u8>, gamepak: Cartridge) -> GameBoyAdvance {
-        cpu: Core,
-        bios_rom: Vec<u8>,
-        gamepak: Cartridge,
-        // TODO rename this "graphics backend"
-        // TODO add sound backend
-        backend: Box<dyn EmulatorBackend>,
-    ) -> GameBoyAdvance {
         let io = IoDevices::new();
         GameBoyAdvance {
-            backend: backend,
             cpu: cpu,
             sysbus: Box::new(SysBus::new(io, bios_rom, gamepak)),
         }
     }
 
-    pub fn frame(&mut self) {
+    pub fn frame(&mut self, video: &mut VideoInterface, input: &mut InputInterface) {
-        self.update_key_state();
+        self.sysbus.io.keyinput = input.poll();
         while self.sysbus.io.gpu.state != GpuState::VBlank {
             self.step_new();
         }
+        video.render(self.sysbus.io.gpu.get_framebuffer());
         while self.sysbus.io.gpu.state == GpuState::VBlank {
             self.step_new();
         }
     }
 
-    pub fn update_key_state(&mut self) {
-        self.sysbus.io.keyinput = self.backend.get_key_state();
-    }
-
     pub fn add_breakpoint(&mut self, addr: u32) -> Option<usize> {
         if !self.cpu.breakpoints.contains(&addr) {
             let new_index = self.cpu.breakpoints.len();
@@ -100,7 +89,6 @@ impl GameBoyAdvance {
         if let Some(new_gpu_state) = io.gpu.step(cycles, &mut self.sysbus, &mut irqs) {
             match new_gpu_state {
                 GpuState::VBlank => {
-                    self.backend.render(io.gpu.get_framebuffer());
                     io.dmac.notify_vblank();
                 }
                 GpuState::HBlank => io.dmac.notify_hblank(),

src/debugger/command.rs

@@ -102,31 +102,31 @@ impl Debugger {
                 }
                 println!("{}\n", self.gba.cpu);
             }
-            Continue => {
+            // Continue => {
-                self.ctrlc_flag.store(true, Ordering::SeqCst);
+            //     self.ctrlc_flag.store(true, Ordering::SeqCst);
-                while self.ctrlc_flag.load(Ordering::SeqCst) {
+            //     while self.ctrlc_flag.load(Ordering::SeqCst) {
-                    let start_time = time::Instant::now();
+            //         let start_time = time::Instant::now();
-                    self.gba.update_key_state();
+            //         self.gba.update_key_state();
-                    match self.gba.check_breakpoint() {
+            //         match self.gba.check_breakpoint() {
-                        Some(addr) => {
+            //             Some(addr) => {
-                            println!("Breakpoint reached! @{:x}", addr);
+            //                 println!("Breakpoint reached! @{:x}", addr);
-                            break;
+            //                 break;
-                        }
+            //             }
-                        _ => {
+            //             _ => {
-                            self.gba.step_new();
+            //                 self.gba.step_new();
-                        }
+            //             }
-                    }
+            //         }
-                }
+            //     }
-            }
+            // }
-            Frame(count) => {
+            // Frame(count) => {
-                use super::time::PreciseTime;
+            //     use super::time::PreciseTime;
-                let start = PreciseTime::now();
+            //     let start = PreciseTime::now();
-                for _ in 0..count {
+            //     for _ in 0..count {
-                    self.gba.frame();
+            //         self.gba.frame();
-                }
+            //     }
-                let end = PreciseTime::now();
+            //     let end = PreciseTime::now();
-                println!("that took {} seconds", start.to(end));
+            //     println!("that took {} seconds", start.to(end));
-            }
+            // }
             HexDump(addr, nbytes) => {
                 let bytes = self.gba.sysbus.get_bytes(addr..addr + nbytes);
                 hexdump::hexdump(&bytes);
@@ -206,6 +206,7 @@ impl Debugger {
                     self.gba.sysbus.io.timers.trace = !self.gba.sysbus.io.timers.trace;
                 }
             }
+            _ => println!("Not Implemented",),
         }
     }
 

src/lib.rs

@@ -25,7 +25,27 @@ extern crate zip;
 
 #[macro_use]
 pub mod util;
-pub mod backend;
 pub mod core;
 pub mod debugger;
 pub mod disass;
+
+pub trait VideoInterface {
+    fn render(&mut self, buffer: &[u32]);
+}
+
+pub trait AudioInterface {
+    fn get_sample_rate(&self);
+}
+
+pub trait InputInterface {
+    fn poll(&mut self) -> u16;
+}
+
+pub mod prelude {
+    pub use super::core::arm7tdmi;
+    pub use super::core::cartridge::Cartridge;
+    pub use super::core::{GBAError, GBAResult, GameBoyAdvance};
+    pub use super::debugger::Debugger;
+    pub use super::util::read_bin_file;
+    pub use super::{AudioInterface, InputInterface, VideoInterface};
+}

src/plat/sdl2/audio.rs

@@ -0,0 +1 @@
+const SAMPLE_RATE: u32 = 44100;

src/plat/sdl2/cli.yml

@@ -1,6 +1,6 @@
-name: rustboyadvance-ng
+name: rba-sdl2
 author: Michel Heily <michelheily@gmail.com>
-about: Game boy advance emulator and debugger
+about: RustBoyAdvance SDL2 port
 args:
     - bios:
         help: Sets the bios file to use
@@ -19,12 +19,6 @@ args:
     - no_framerate_limit:
         long: no-framerate-limit
         help: Run without frame limiter
-    - backend:
-        long: backend
-        takes_value: true
-        possible_values: [ sdl2, minifb ]
-        default_value: minifb
-        required: false
     - debug:
         long: debug
         help: Start with the debugger attached

src/plat/sdl2/keyboard.rs

@@ -0,0 +1,64 @@
+use sdl2::keyboard::Keycode;
+use sdl2::{event::Event, EventPump};
+
+use rustboyadvance_ng::core::keypad as gba_keypad;
+use rustboyadvance_ng::InputInterface;
+
+extern crate bit;
+use bit::BitIndex;
+
+pub struct PlatformSdl2_Keyboard {
+    event_pump: EventPump,
+    keyinput: u16,
+}
+
+impl InputInterface for PlatformSdl2_Keyboard {
+    fn poll(&mut self) -> u16 {
+        for event in self.event_pump.poll_iter() {
+            match event {
+                Event::KeyDown {
+                    keycode: Some(keycode),
+                    ..
+                } => {
+                    if let Some(key) = keycode_to_keypad(keycode) {
+                        self.keyinput.set_bit(key as usize, false);
+                    }
+                }
+                Event::KeyUp {
+                    keycode: Some(keycode),
+                    ..
+                } => {
+                    if let Some(key) = keycode_to_keypad(keycode) {
+                        self.keyinput.set_bit(key as usize, true);
+                    }
+                }
+                Event::Quit { .. } => panic!("quit!"),
+                _ => {}
+            }
+        }
+        self.keyinput
+    }
+}
+
+fn keycode_to_keypad(keycode: Keycode) -> Option<gba_keypad::Keys> {
+    match keycode {
+        Keycode::Up => Some(gba_keypad::Keys::Up),
+        Keycode::Down => Some(gba_keypad::Keys::Down),
+        Keycode::Left => Some(gba_keypad::Keys::Left),
+        Keycode::Right => Some(gba_keypad::Keys::Right),
+        Keycode::Z => Some(gba_keypad::Keys::ButtonB),
+        Keycode::X => Some(gba_keypad::Keys::ButtonA),
+        Keycode::Return => Some(gba_keypad::Keys::Start),
+        Keycode::Space => Some(gba_keypad::Keys::Select),
+        Keycode::A => Some(gba_keypad::Keys::ButtonL),
+        Keycode::S => Some(gba_keypad::Keys::ButtonR),
+        _ => None,
+    }
+}
+
+pub fn create_keyboard(sdl: &sdl2::Sdl) -> PlatformSdl2_Keyboard {
+    PlatformSdl2_Keyboard {
+        event_pump: sdl.event_pump().unwrap(),
+        keyinput: gba_keypad::KEYINPUT_ALL_RELEASED,
+    }
+}

src/plat/sdl2/main.rs

@@ -0,0 +1,78 @@
+extern crate sdl2;
+use sdl2::Sdl;
+
+use std::path::Path;
+use std::time;
+
+#[macro_use]
+extern crate clap;
+
+mod audio;
+mod keyboard;
+mod video;
+
+use keyboard::{create_keyboard, PlatformSdl2_Keyboard};
+use video::{create_video_interface, PlatformSdl2_VideoInterface};
+
+#[macro_use]
+extern crate rustboyadvance_ng;
+use rustboyadvance_ng::prelude::*;
+use rustboyadvance_ng::util::FpsCounter;
+
+fn main() {
+    let yaml = load_yaml!("cli.yml");
+    let matches = clap::App::from_yaml(yaml).get_matches();
+
+    let skip_bios = matches.occurrences_of("skip_bios") != 0;
+    let no_framerate_limit = matches.occurrences_of("no_framerate_limit") != 0;
+    let debug = matches.occurrences_of("debug") != 0;
+
+    let bios_path = Path::new(matches.value_of("bios").unwrap_or_default());
+    let rom_path = Path::new(matches.value_of("game_rom").unwrap());
+    let rom_name = rom_path.file_name().unwrap().to_str().unwrap();
+
+    let bios_bin = read_bin_file(bios_path).unwrap();
+    let cart = Cartridge::from_path(rom_path).unwrap();
+    let mut cpu = arm7tdmi::Core::new();
+    if skip_bios {
+        cpu.skip_bios();
+    }
+    let cpu = cpu;
+
+    let sdl_context = sdl2::init().unwrap();
+    let mut video = create_video_interface(&sdl_context);
+    let mut keyboard = create_keyboard(&sdl_context);
+
+    let mut fps_counter = FpsCounter::default();
+    let mut gba = GameBoyAdvance::new(cpu, bios_bin, cart);
+
+    if debug {
+        gba.cpu.set_verbose(true);
+        let mut debugger = Debugger::new(gba);
+        println!("starting debugger...");
+        debugger.repl(matches.value_of("script_file")).unwrap();
+        println!("ending debugger...");
+    } else {
+        let frame_time = time::Duration::new(0, 1_000_000_000u32 / 60);
+        loop {
+            let start_time = time::Instant::now();
+
+            gba.frame(&mut video, &mut keyboard);
+            if let Some(fps) = fps_counter.tick() {
+                let title = format!("{} ({} fps)", rom_name, fps);
+                video.set_window_title(&title);
+            }
+
+            if !no_framerate_limit {
+                let time_passed = start_time.elapsed();
+                let delay = frame_time.checked_sub(time_passed);
+                match delay {
+                    None => {}
+                    Some(delay) => {
+                        ::std::thread::sleep(delay);
+                    }
+                };
+            }
+        }
+    }
+}

src/plat/sdl2/video.rs

@@ -0,0 +1,77 @@
+use sdl2::pixels::{Color, PixelFormatEnum};
+use sdl2::rect::{Point, Rect};
+use sdl2::render::{TextureCreator, WindowCanvas};
+use sdl2::video::WindowContext;
+use sdl2::Sdl;
+
+use rustboyadvance_ng::core::gpu::{DISPLAY_HEIGHT, DISPLAY_WIDTH};
+use rustboyadvance_ng::util::FpsCounter;
+use rustboyadvance_ng::VideoInterface;
+
+const SCREEN_WIDTH: u32 = DISPLAY_WIDTH as u32;
+const SCREEN_HEIGHT: u32 = DISPLAY_HEIGHT as u32;
+const SCALE: u32 = 3; // TODO control via CLI & support window resize
+
+pub struct PlatformSdl2_VideoInterface {
+    tc: TextureCreator<WindowContext>,
+    canvas: WindowCanvas,
+    fps_counter: FpsCounter,
+}
+
+impl PlatformSdl2_VideoInterface {
+    pub fn set_window_title(&mut self, title: &str) {
+        self.canvas.window_mut().set_title(&title);
+    }
+}
+
+impl VideoInterface for PlatformSdl2_VideoInterface {
+    fn render(&mut self, buffer: &[u32]) {
+        let mut texture = self
+            .tc
+            .create_texture_target(PixelFormatEnum::RGB24, SCREEN_WIDTH, SCREEN_HEIGHT)
+            .unwrap();
+        self.canvas
+            .with_texture_canvas(&mut texture, |texture_canvas| {
+                for y in 0i32..(SCREEN_HEIGHT as i32) {
+                    for x in 0i32..(SCREEN_WIDTH as i32) {
+                        let c = buffer[index2d!(x, y, SCREEN_WIDTH as i32) as usize];
+                        let color = Color::RGB((c >> 16) as u8, (c >> 8) as u8, c as u8);
+                        texture_canvas.set_draw_color(color);
+                        let _ = texture_canvas.draw_point(Point::from((x, y)));
+                    }
+                }
+            })
+            .unwrap();
+        self.canvas
+            .copy(
+                &texture,
+                None,
+                Some(Rect::new(0, 0, SCREEN_WIDTH * SCALE, SCREEN_HEIGHT * SCALE)),
+            )
+            .unwrap();
+        self.canvas.present();
+    }
+}
+
+pub fn create_video_interface(sdl: &Sdl) -> PlatformSdl2_VideoInterface {
+    let video_subsystem = sdl.video().unwrap();
+    let window = video_subsystem
+        .window(
+            "RustBoyAdvance",
+            SCREEN_WIDTH * SCALE,
+            SCREEN_HEIGHT * SCALE,
+        )
+        .opengl()
+        .position_centered()
+        .build()
+        .unwrap();
+    let mut canvas = window.into_canvas().accelerated().build().unwrap();
+    canvas.set_draw_color(Color::RGB(0, 0, 0));
+    canvas.clear();
+    let tc = canvas.texture_creator();
+    PlatformSdl2_VideoInterface {
+        tc: tc,
+        canvas: canvas,
+        fps_counter: Default::default(),
+    }
+}

src/util.rs

@@ -1,14 +1,44 @@
 use std::fs::File;
 use std::io;
 use std::io::prelude::*;
+use std::path::Path;
+use std::time;
 
-pub fn read_bin_file(filename: &str) -> io::Result<Vec<u8>> {
+pub fn read_bin_file(filename: &Path) -> io::Result<Vec<u8>> {
     let mut buf = Vec::new();
     let mut file = File::open(filename)?;
     file.read_to_end(&mut buf)?;
     Ok(buf)
 }
 
+pub struct FpsCounter {
+    count: u32,
+    timer: time::Instant,
+}
+
+impl Default for FpsCounter {
+    fn default() -> FpsCounter {
+        FpsCounter {
+            count: 0,
+            timer: time::Instant::now(),
+        }
+    }
+}
+
+impl FpsCounter {
+    pub fn tick(&mut self) -> Option<u32> {
+        self.count += 1;
+        if self.timer.elapsed() >= time::Duration::from_secs(1) {
+            let fps = self.count;
+            self.timer = time::Instant::now();
+            self.count = 0;
+            Some(fps)
+        } else {
+            None
+        }
+    }
+}
+
 #[macro_export]
 macro_rules! index2d {
     ($x:expr, $y:expr, $w:expr) => {