softbuffer/examples/animation.rs

92 lines
3 KiB
Rust

use instant::Instant;
#[cfg(not(target_arch = "wasm32"))]
use rayon::prelude::*;
use std::f64::consts::PI;
use softbuffer::GraphicsContext;
use winit::event::{Event, WindowEvent};
use winit::event_loop::{ControlFlow, EventLoop};
use winit::window::WindowBuilder;
fn main() {
let event_loop = EventLoop::new();
let window = WindowBuilder::new().build(&event_loop).unwrap();
#[cfg(target_arch = "wasm32")]
{
use winit::platform::web::WindowExtWebSys;
web_sys::window()
.unwrap()
.document()
.unwrap()
.body()
.unwrap()
.append_child(&window.canvas())
.unwrap();
}
let mut graphics_context = unsafe { GraphicsContext::new(&window, &window) }.unwrap();
let mut old_size = (0, 0);
let mut frames = pre_render_frames(0, 0);
let start = Instant::now();
event_loop.run(move |event, _, control_flow| {
*control_flow = ControlFlow::Poll;
match event {
Event::RedrawRequested(window_id) if window_id == window.id() => {
let elapsed = start.elapsed().as_secs_f64() % 1.0;
let (width, height) = {
let size = window.inner_size();
(size.width, size.height)
};
if (width, height) != old_size {
old_size = (width, height);
frames = pre_render_frames(width as usize, height as usize);
};
let buffer = &frames[((elapsed * 60.0).round() as usize).clamp(0, 59)];
graphics_context.set_buffer(buffer.as_slice(), width as u16, height as u16);
}
Event::MainEventsCleared => {
window.request_redraw();
}
Event::WindowEvent {
event: WindowEvent::CloseRequested,
window_id,
} if window_id == window.id() => {
*control_flow = ControlFlow::Exit;
}
_ => {}
}
});
}
fn pre_render_frames(width: usize, height: usize) -> Vec<Vec<u32>> {
let render = |frame_id| {
let elapsed = ((frame_id as f64) / (60.0)) * 2.0 * PI;
(0..(width * height))
.map(|index| {
let y = ((index / width) as f64) / (height as f64);
let x = ((index % width) as f64) / (width as f64);
let red =
((((y + elapsed).sin() * 0.5 + 0.5) * 255.0).round() as u32).clamp(0, 255);
let green =
((((x + elapsed).sin() * 0.5 + 0.5) * 255.0).round() as u32).clamp(0, 255);
let blue =
((((y - elapsed).cos() * 0.5 + 0.5) * 255.0).round() as u32).clamp(0, 255);
blue | (green << 8) | (red << 16)
})
.collect::<Vec<_>>()
};
#[cfg(target_arch = "wasm32")]
return (0..60).map(render).collect();
#[cfg(not(target_arch = "wasm32"))]
(0..60).into_par_iter().map(render).collect()
}