struct Particle {
    pos: vec4<f32>,
    vel: vec4<f32>,
    rot: vec4<f32>,
    color: vec4<f32>,
};

struct Uniforms {
    audio_peak: f32,
    aspect_ratio: f32,
    time: f32,
    beat: f32,
};

@group(0) @binding(0) var<storage, read_write> particles: array<Particle>;
@group(0) @binding(1) var<uniform> uniforms: Uniforms;

@compute @workgroup_size(64)
fn main(@builtin(global_invocation_id) id: vec3<u32>) {
    let i = id.x;
    if (i >= arrayLength(&particles)) {
        return;
    }
    var p = particles[i];
    let new_pos = p.pos.xyz + p.vel.xyz * 0.016;
    p.pos = vec4<f32>(new_pos, p.pos.w);
    p.vel.y = p.vel.y - 0.01 * (1.0 + uniforms.audio_peak * 5.0);
    p.rot.x = p.rot.x + p.rot.y * 0.016;
    if (p.pos.y < -1.5) {
        p.pos.y = 1.5;
        p.pos.x = (f32(i % 100u) / 50.0) - 1.0 + (uniforms.audio_peak * 0.5);
        p.vel.y = 0.0;
    }
    particles[i] = p;
}