AyuGramDesktop/Telegram/shaders/thanos_init.comp

#version 450

layout(local_size_x = 64) in;

struct Particle {
	vec2 offset;
	vec2 velocity;
	float lifetime;
	float _pad;
};

layout(std430, binding = 0) buffer Particles {
	Particle particles[];
};

layout(std140, binding = 1) uniform Params {
	uint particleCountX;
	uint particleCountY;
	uint seed;
	uint _pad;
};

uint hash(uint x) {
	x ^= x >> 16u;
	x *= 0x45d9f3bu;
	x ^= x >> 16u;
	x *= 0x45d9f3bu;
	x ^= x >> 16u;
	return x;
}

float hashFloat(uint x) {
	return float(hash(x)) / float(0xFFFFFFFFu);
}

void main() {
	uint gid = gl_GlobalInvocationID.x;
	uint count = particleCountX * particleCountY;
	if (gid >= count) {
		return;
	}

	uint s = gid * 3u + seed;

	float direction = hashFloat(s) * (3.14159265 * 2.0);
	float speed = (0.1 + hashFloat(s + 1u) * 0.1) * 320.0;

	Particle p;
	p.offset = vec2(0.0, 0.0);
	p.velocity = vec2(cos(direction) * speed, sin(direction) * speed);
	p.lifetime = 1.5 + hashFloat(s + 2u) * 1.5;
	p._pad = 0.0;

	particles[gid] = p;
}