// Native hit-liquid policy (00ab9a90). Called at the damage source, once per channel.
struct HitLiquidPolicy { uvec4 liquid; uvec4 state; vec4 bounds; vec4 inventory; vec4 pressure; };
layout(std430, set = 0, binding = 67) readonly buffer HitLiquid {
    ivec4 bloodSettings;
    HitLiquidPolicy bloodPolicy[4096];
    vec4 bloodProjectile[512];
};
void hit_liquid(int target, float damage, vec2 hit, vec2 impulse, float incoming, float speedScale, int fx, uint seed) {
    if (damage <= 0.0 || incoming <= 0.0 || fx == 0 || (bloodPolicy[target].state.x & 2u) != 0u) return;
    const uvec4 policy = bloodPolicy[target].liquid;
    int matp1 = int(policy.x & 65535u);
    uint colour = policy.z;
    if (bloodSettings.y != 0 && (policy.x >> 16) != 0u) { matp1 = int(policy.x >> 16); colour = policy.w; }
    if (matp1 == 0) return;
    const float u = float(hash3(seed, 0u, 11u) & 32767u) / 32767.0;
    const int count = int(((u * 20.0 + 20.0) * uintBitsToFloat(policy.y) + 0.5) * incoming) * bloodSettings.x;
    vec2 v = impulse;
    for (int k = 0; k < count; ++k) {
        const float su = float(hash3(seed, uint(k), 12u) & 32767u) / 32767.0;
        const float au = float(hash3(seed, uint(k), 13u) & 32767u) / 32767.0;
        const float yu = float(hash3(seed, uint(k), 14u) & 32767u) / 32767.0;
        const float xu = float(hash3(seed, uint(k), 15u) & 32767u) / 32767.0;
        const float a = -0.6 + 1.2 * au;
        v = vec2(v.x * cos(a) - v.y * sin(a), v.x * sin(a) + v.y * cos(a));
        // The constructor adds +0.5 after the hit handler's +/-1.5 jitter.
        const vec2 pos = hit - vec2(1.0) + 3.0 * vec2(xu, yu);
        const ivec2 p = ivec2(floor(pos)) - ivec2(pc.view_x, pc.view_y);
        if (any(lessThan(p, ivec2(0))) || any(greaterThanEqual(p, ivec2(pc.gw, pc.gh)))) continue;
        emit_material_particle(pos, v * ((20.0 / 60.0) * (0.5 + 0.75 * su) * speedScale), 70.0 + au * 40.0, PART_GRAV, colour, matp1 - 1);
    }
}