def create_world(self):
from creatures import Predator, Herbivore, Plant
if self.density < 1 or self.density > 100:
sys.exit()
world = World(cols=self.cols, rows=self.rows)
cnt = int(world.cols * world.rows * 0.01 * self.density / 3)
for i in xrange(cnt):
pos = world.get_rnd_free_space()
if pos is None:
break
creature = Predator(x=pos[0], y=pos[1])
world.queue.append((i * 21, creature))
for i in xrange(cnt):
pos = world.get_rnd_free_space()
if pos is None:
break
creature = Herbivore(x=pos[0], y=pos[1])
world.queue.append((i * 22, creature))
for i in xrange(cnt):
pos = world.get_rnd_free_space()
if pos is None:
break
creature = Plant(x=pos[0], y=pos[1])
world.queue.append((i * 23, creature))
world.start(0.1)
return world
