hypoloop/examples/buffer.rs
2021-08-12 15:53:36 -07:00

137 lines
3.9 KiB
Rust

#![deny(clippy::all)]
#![forbid(unsafe_code)]
use hypoloop::core::{State, Loop};
use rand::Rng;
use log::error;
use pixels::{Error, Pixels, SurfaceTexture};
use winit::dpi::LogicalSize;
use winit::event::{Event, VirtualKeyCode};
use winit::event_loop::{ControlFlow, EventLoop};
use winit::window::WindowBuilder;
use winit_input_helper::WinitInputHelper;
const WIDTH: u32 = 500;
const HEIGHT: u32 = 500;
const BOX_SIZE: i16 = 64;
/// Representation of the application state. In this example, a box will bounce around the screen.
struct World {
target: [i16; 2]
}
fn main() -> Result<(), Error> {
env_logger::init();
let event_loop = EventLoop::new();
let mut input = WinitInputHelper::new();
let window = {
let size = LogicalSize::new(WIDTH as f64, HEIGHT as f64);
WindowBuilder::new()
.with_title("Hello Pixels")
.with_inner_size(size)
.with_min_inner_size(size)
.build(&event_loop)
.unwrap()
};
let mut pixels = {
let window_size = window.inner_size();
let surface_texture = SurfaceTexture::new(window_size.width, window_size.height, &window);
Pixels::new(WIDTH, HEIGHT, surface_texture)?
};
let mut world = World::new();
// create sim with default configuration
let mut sim = Loop::new();
//sim.set_update_interval(10);
let mut update_logic = move |state: &mut State| {
// print information about the current tick's timings
state.debug_time();
world.update(state.get_timestep());
world.draw(pixels.get_frame());
if pixels
.render()
.map_err(|e| error!("pixels.render() failed: {}", e))
.is_err()
{
state.pause();
return;
}
};
// create a closure containing your display logic
let mut display_logic = move |state: &mut State| {
// Draw the current frame
window.request_redraw();
};
sim.init();
event_loop.run(move |event, _, control_flow| {
// Handle input events
if input.update(&event) {
// Close events
if input.key_pressed(VirtualKeyCode::Escape) || input.quit() {
*control_flow = ControlFlow::Exit;
return;
}
}
// step the sim forward
sim.step(&mut update_logic, &mut display_logic);
});
}
impl World {
/// Create a new `World` instance that can draw a moving box.
fn new() -> Self {
Self {
target: [0, 0]
}
}
/// Update the `World` internal state; bounce the box around the screen.
fn update(&mut self, timestep: f32) {
let speed: f32 = 500.0;
let mut new_target = self.target;
// update the target
if new_target[0] < WIDTH as i16 {
new_target[0] += (speed * timestep) as i16;
} else {
new_target[0] = 0;
}
self.target = new_target;
}
/// Draw the `World` state to the frame buffer.
///
/// Assumes the default texture format: `wgpu::TextureFormat::Rgba8UnormSrgb`
fn draw(&self, frame: &mut [u8]) {
for (i, pixel) in frame.chunks_exact_mut(4).enumerate() {
let x = (i % WIDTH as usize) as i16;
let y = (i / WIDTH as usize) as i16;
let mut old_pixel = [0u8; 4];
for j in 0..4 {
// get the old pixel and decay it
old_pixel[j] = pixel[j];
if old_pixel[j] > 0 {
old_pixel[j] -= 1;
}
}
let condition = x <= self.target[0];
let rgba = if condition {
[0xff, 0x00, 0x00, 0xff]
} else {
old_pixel
};
pixel.copy_from_slice(&rgba);
}
}
}