int numberToSpawn = engine.zsp.getNumberToSpawn();
if (numberToSpawn <= 0)
return;
double lightLevel = engine.getAmbientLight() - abt.naturalLightLevel*1.0/BlockTransparent.MAX_LIGHT_LEVEL;
if (lightLevel < .5 && Util.hashToDouble(Util.hash(Hexel.session.seed, step, bx, by, bz)) < .25){
Zombie zombie = new Zombie(x, y, z, engine.getThingBridge());
engine.addThing(zombie);
engine.zsp.spawnZombies(1);
}
}