src/effects/particle_compute.wgsl


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// Particle simulation (compute shader) - V2
struct Particle {
    pos: vec4f,
    vel: vec4f,
    rot: vec4f,
    color: vec4f,
};

#include "sequence_uniforms"

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

@compute @workgroup_size(64)
fn main(@builtin(global_invocation_id) id: vec3u) {
    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 = vec4f(new_pos, p.pos.w);
    p.vel.y = p.vel.y - 0.01 * (1.0 + uniforms.audio_intensity * 5.0);
    p.rot.x = p.rot.x + p.rot.y * 0.016;
    if (p.pos.y < -1.5) {
        // Stagger respawn height by index (golden ratio) to break synchronization
        p.pos.y = 1.5 + fract(f32(i) * 0.6180339) * 3.0;
        p.pos.x = (f32(i % 100u) / 50.0) - 1.0 + (uniforms.audio_intensity * 0.5);
        p.vel.y = 0.0;
    }
    particles[i] = p;
}