nannou-sketches/02_gravity/src/main.rs

119 lines
2.8 KiB
Rust

use sketchlib::nannou;
use sketchlib::prelude::*;
fn main() {
nannou::app(model)
.size(1260, 1260)
.update(update)
.simple_window(view)
.run();
}
#[derive(Clone)]
struct Body {
pos: DVec2,
vel: DVec2,
mass: i64,
color: Rgb,
}
struct Model {
bodies: Vec<Body>,
}
fn model(_app: &App) -> Model {
let mut bodies = Vec::new();
const MASS_SUN: i64 = 50000000000000000;
bodies.push(Body {
pos: (0.0, 0.0).into(),
vel: (0.0, 0.0).into(),
mass: MASS_SUN,
color: rgb(1.0, 1.0, 1.0),
});
const G: f64 = 6.67408e-11;
let palette = &[
rgb(85.0 / 255.0, 205.0 / 255.0, 252.0 / 255.0),
rgb(1.0, 1.0, 1.0),
rgb(247.0 / 255.0, 168.0 / 255.0, 184.0 / 255.0),
];
let mut theta = 0.0;
for i in 1..=256 {
let r = 25.0 + 5.0 * i as f64;
let m = 50000000000u64 / i;
let curr_color = palette[i as usize % palette.len()];
let speed = (G * MASS_SUN as f64 / r).sqrt();
println!("{}", speed);
bodies.push(Body {
pos: (r * theta.cos(), r * theta.sin()).into(),
vel: (speed * theta.sin(), speed * -theta.cos()).into(),
mass: m as i64,
color: curr_color,
});
theta += 1.94161103873;
}
Model { bodies }
}
fn update(app: &App, model: &mut Model, _update: Update) {
const G: f64 = 6.67408e-11;
let bodies = model.bodies.clone();
let delta_t = delta_t(&app);
model
.bodies
.par_iter_mut()
.enumerate()
.for_each(|(i, body)| {
let mut acc: DVec2 = (0.0, 0.0).into();
bodies.iter().enumerate().for_each(|(j, other_body)| {
if i == j {
return;
}
let delta = other_body.pos - body.pos;
let dist_sq = body.pos.distance_squared(other_body.pos);
if dist_sq <= (body.mass as f64).log10() {
return;
}
let acceleration = G * other_body.mass as f64 / dist_sq;
acc += delta * acceleration / dist_sq.sqrt();
});
body.vel += acc * delta_t;
body.pos += body.vel * delta_t;
});
}
fn view(app: &App, model: &Model, frame: Frame) {
// let t = app.duration.since_start.as_secs_f64();
let draw = app.draw().scale(1.0);
draw.background().color(BLACK);
for body in model.bodies.iter() {
let diameter = (body.mass as f32).log10() * 2.0; // should be proportional to cuberoot but this is so we can actually see the small ones
draw.ellipse()
.w_h(diameter, diameter)
.xy(body.pos.as_f32())
.color(body.color);
}
draw.to_frame(app, &frame).unwrap();
dump_frame(app, &frame).unwrap();
}