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extern crate nccl;
extern crate time;
extern crate sdl2;
use sdl2::pixels::Color;
use sdl2::event::Event;
pub use sdl2::keyboard::Keycode;
pub mod error;
pub mod settings;
pub mod game;
pub mod graphics;
use error::*;
use game::*;
use graphics::Graphics;
use settings::Settings;
pub fn game_loop<T: GameState>(mut game: T, settings: Settings) -> AsteroidResult {
let sdl_context = sdl2::init().unwrap();
let window_builder = sdl_context.video().unwrap();
let window = window_builder.window(&settings.title, settings.width, settings.height)
.opengl()
.position_centered()
.build().unwrap();
let canvas = window.into_canvas();
let mut canvas = if settings.vsync {
canvas.present_vsync()
} else { canvas }.build().unwrap();
canvas.set_draw_color(Color::RGB(0, 0, 0));
canvas.clear();
canvas.present();
let mut event_loop = sdl_context.event_pump().unwrap();
let mut err = None;
let mut args = Args::new();
let mut graphics = Graphics::new(canvas);
let mut current_time = time::precise_time_s();
let dt = 1./180.;
let mut frames = 0;
let mut second = 0.;
while err.is_none() {
let mut steps = 0;
let new_time = time::precise_time_s();
let mut frame_time = new_time - current_time;
current_time = new_time;
while frame_time > 0. {
let delta_time = if frame_time <= dt { frame_time } else { dt };
for event in event_loop.poll_iter() {
match event {
Event::Quit {..} => err = Some(AsteroidResult::Ok),
Event::KeyDown { keycode: Some(Keycode::Escape), .. } => {
if settings.exit_on_escape {
err = Some(AsteroidResult::Ok);
} else {
game.keyboard_input(Keycode::Escape);
}
},
Event::KeyDown { keycode: Some(key), .. } => {
if !args.is_down(key) {
args.set_key_down(key);
}
},
Event::KeyUp { keycode: Some(key), .. } => {
args.set_key_up(key);
}
_ => {}
}
}
graphics.canvas.set_draw_color(Color::RGB(0, 0, 0));
graphics.canvas.clear();
second += delta_time;
args.set_dt(delta_time);
game.update(&mut args);
frame_time -= delta_time;
steps += 1;
if steps >= 500 {
println!("spiral averted");
break;
}
}
game.render(&mut args, &mut graphics);
frames += 1;
if second >= 1. {
second = 0.;
frames = 0;
}
args.set_fps(frames as f64 / second);
graphics.canvas.present();
}
err.unwrap()
}