pragma mark -- 流星Animation

• (void)staranimationWithImageView:(UIImageView *)imageView imagePoint:(CGPoint)point {
  CAEmitterLayer *rainLayer = [CAEmitterLayer layer];
  [rainLayer setEmitterPosition:point];
  [rainLayer setEmitterSize:CGSizeMake(VKLCLength(400), VKLCLength(200))];
  // 发射模式
  [rainLayer setEmitterMode:kCAEmitterLayerLine];
  [rainLayer setEmitterShape:kCAEmitterLayerLine];
  [rainLayer setRenderMode:kCAEmitterLayerAdditive];

  CAEmitterCell *rainCell = [CAEmitterCell emitterCell];
  [rainCell setBirthRate:1];
  [rainCell setVelocity:100];
  [rainCell setXAcceleration:-200];
  [rainCell setYAcceleration:85];
  [rainCell setScale:0.1];
  [rainCell setScaleSpeed:0.2];
  [rainCell setLifetime:1.8];
  [rainCell setEmissionLongitude: 55 * (180.0 / M_PI)];
  [rainCell setContents:(id)[[VKLCImageUtil getImageWithName:@"vklc_starRain"] CGImage]];
  [rainCell setColor:[[UIColor colorWithRed:1 green:1 blue:1 alpha:0.6] CGColor]];

  [rainLayer setEmitterDepth:10];
  rainLayer.emitterCells = [NSArray arrayWithObject:rainCell];
  [imageView.layer addSublayer:rainLayer];
  }