Add sdl2 backend

Currently has bad performance


Former-commit-id: 384ef6b5cd7b1e1baeb6adfbc0b299b0d07d7a5d

src/backend/minifb_backend.rs

@@ -6,10 +6,9 @@ extern crate minifb;
 
 use minifb::{Key, Window, WindowOptions};
 
-use super::backend::EmulatorBackend;
+use super::EmulatorBackend;
 use crate::core::gpu::Gpu;
-
+use crate::core::keypad;
-use super::core::keypad;
 
 pub struct MinifbBackend {
     window: Window,
@@ -41,18 +40,17 @@ impl MinifbBackend {
 
 impl EmulatorBackend for MinifbBackend {
     fn render(&mut self, buffer: Vec<u32>) {
-        let now = time::Instant::now();
+        self.frames_rendered += 1;
-        if now - self.first_frame_start >= time::Duration::from_secs(1) {
+        if self.first_frame_start.elapsed() >= time::Duration::from_secs(1) {
             let title = format!("rustboyadvance-ng ({} fps)", self.frames_rendered);
             self.window.set_title(&title);
-            self.first_frame_start = now;
+            self.first_frame_start = time::Instant::now();
             self.frames_rendered = 0;
         }
         self.window.update_with_buffer(&buffer).unwrap();
-        self.frames_rendered += 1;
     }
 
-    fn get_key_state(&self) -> u16 {
+    fn get_key_state(&mut self) -> u16 {
         let mut keyinput = keypad::KEYINPUT_ALL_RELEASED;
         keyinput.set_bit(keypad::Keys::Up as usize, !self.window.is_key_down(Key::Up));
         keyinput.set_bit(

src/backend/mod.rs

@@ -1,11 +1,15 @@
 use super::core::keypad;
 
-pub use super::minifb_backend::MinifbBackend;
+mod minifb_backend;
+pub use minifb_backend::MinifbBackend;
+
+mod sdl2_backend;
+pub use sdl2_backend::Sdl2Backend;
 
 pub trait EmulatorBackend {
     fn render(&mut self, buffer: Vec<u32>);
 
-    fn get_key_state(&self) -> u16;
+    fn get_key_state(&mut self) -> u16;
 }
 
 pub struct DummyBackend;
@@ -17,7 +21,7 @@ impl DummyBackend {
 }
 
 impl EmulatorBackend for DummyBackend {
-    fn get_key_state(&self) -> u16 {
+    fn get_key_state(&mut self) -> u16 {
         keypad::KEYINPUT_ALL_RELEASED
     }
     fn render(&mut self, _buffer: Vec<u32>) {}

src/backend/sdl2_backend.rs

@@ -0,0 +1,132 @@
+use std::time;
+use std::convert::TryFrom;
+
+use crate::bit::BitIndex;
+
+extern crate sdl2;
+use sdl2::event::Event;
+use sdl2::keyboard::Keycode;
+use sdl2::pixels::{Color, PixelFormat, PixelFormatEnum};
+use sdl2::rect::{Point, Rect};
+use sdl2::render::{Texture, TextureCreator, WindowCanvas};
+use sdl2::video::{Window, WindowContext};
+
+use super::EmulatorBackend;
+use crate::core::gpu::Gpu;
+use crate::core::keypad;
+
+pub struct Sdl2Backend {
+    event_pump: sdl2::EventPump,
+    tc: TextureCreator<WindowContext>,
+    canvas: WindowCanvas,
+    frames_rendered: u32,
+    fps_timer: time::Instant,
+    keyinput: u16,
+}
+
+const SCREEN_WIDTH: u32 = Gpu::DISPLAY_WIDTH as u32;
+const SCREEN_HEIGHT: u32 = Gpu::DISPLAY_HEIGHT as u32;
+
+impl Sdl2Backend {
+    pub fn new() -> Sdl2Backend {
+        let sdl_context = sdl2::init().unwrap();
+        let video_subsystem = sdl_context.video().unwrap();
+
+        let window = video_subsystem
+            .window("RustBoyAdvance", SCREEN_WIDTH, SCREEN_HEIGHT)
+            .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();
+        let event_pump = sdl_context.event_pump().unwrap();
+
+        Sdl2Backend {
+            canvas: canvas,
+            event_pump: event_pump,
+            tc: tc,
+            frames_rendered: 0,
+            fps_timer: time::Instant::now(),
+            keyinput: keypad::KEYINPUT_ALL_RELEASED,
+        }
+    }
+}
+
+impl EmulatorBackend for Sdl2Backend {
+    fn render(&mut self, buffer: Vec<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, SCREEN_HEIGHT)),
+            )
+            .unwrap();
+        self.canvas.present();
+
+        self.frames_rendered += 1;
+        if self.fps_timer.elapsed() >= time::Duration::from_secs(1) {
+            self.fps_timer = time::Instant::now();
+            let title = format!("rustboyadvance-ng ({} fps)", self.frames_rendered);
+            self.canvas.window_mut().set_title(&title);
+            self.frames_rendered = 0;
+        }
+    }
+
+    fn get_key_state(&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<keypad::Keys> {
+    match keycode {
+        Keycode::Up => Some(keypad::Keys::Up),
+        Keycode::Down => Some(keypad::Keys::Down),
+        Keycode::Left => Some(keypad::Keys::Left),
+        Keycode::Right => Some(keypad::Keys::Right),
+        _ => None,
+    }
+}

src/bin/main.rs

@@ -25,7 +25,7 @@ fn run_emulator(matches: &ArgMatches) -> GBAResult<()> {
     };
 
     let backend: Box<EmulatorBackend> = match matches.value_of("backend") {
-        Some("sdl2") => panic!("sdl2 not implemented"),
+        Some("sdl2") => Box::new(Sdl2Backend::new()),
         Some("minifb") => Box::new(MinifbBackend::new()),
         // None => DummyBackend::new(),
         None => Box::new(DummyBackend::new()),

src/lib.rs

@@ -22,4 +22,3 @@ pub mod backend;
 pub mod core;
 pub mod debugger;
 pub mod disass;
-pub mod minifb_backend;