get tilesInView(): TilesInView {
     var startCol: number = _.floor(this.camera.x / this.map.tileWidth);
     var endCol: number = startCol + (this.camera.width / this.map.tileWidth);
     var startRow: number = _.floor(this.camera.y / this.map.tileHeight);
     var endRow: number = startRow + (this.camera.height / this.map.tileHeight);
     return {
         startCol: startCol, 
         endCol: _.min([endCol, this.map.colCount - 1]), 
         startRow: startRow, 
         endRow: _.min([endRow, this.map.rowCount - 1])
     };
 }

async function main() {
  const config = getConfigRoot();
  const bfConfig = findBrokerConfig(config, 'Bitflyer');
  const bfApi = new BitflyerApi(bfConfig.key, bfConfig.secret);
  const bfBalance = await bfApi.getBalance();
  const bfBtc = (bfBalance.find(x => x.currency_code === 'BTC') as Balance).available;
  const request = {
    product_code: 'BTC_JPY',
    child_order_type: 'MARKET',
    side: 'SELL',
    size: _.floor(bfBtc, 4)
  };
  try {
    console.log(`Selling ${bfBtc}...`);
    const response = await bfApi.sendChildOrder(request);
    console.log(response);
  } catch (ex) {
    console.log(ex.message);
  }
}

function roundDown(valueToFloor: number): number {
    return _.floor(valueToFloor)
}

 getFloor(first: number, second: number) {
     return first <= second ? _.floor(first) : _.floor(second);
 }