def draw(self, group):
batch = Batch()
ss = []
for particle in group:
s = Sprite(self.image, batch=batch)
s.position = list(particle.position)[:2]
s.color = [c * 255 for c in list(particle.color)[:3]]
s.scale = particle.size[0] / 64.0
s.rotation = particle.age * 720
s.opacity = particle.color[3] * 255
ss.append(s)
batch.draw()
