bmp rle gen

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;

namespace BitmapRLEGenerator
{
    class Program
    {
        public static int ResX = 1000;
        public static int ResY = 1000;

        static void Main(string[] args)
        {
            FileStream bmp = new FileStream("bmp.bmp", FileMode.Create, FileAccess.ReadWrite);
            bmp.Write(new byte[2] { 0x42, 0x4D }); //"BM"

            List<byte> bbb = new List<byte>();

            int CommandAmountPerLine = ResX / 0xFF; if (CommandAmountPerLine * 0xFF != ResX) { CommandAmountPerLine++; }

            for (int i = 0; i < ResY; i++)
            {
                for (int z = 1; z < CommandAmountPerLine+1; z++)
                {
                    if (ResX - (z * 255) > 0)
                    {
                        bbb.Add(0xFF);
                        bbb.Add(0xFF);
                    } else
                    {
                        bbb.Add((byte)(ResX % 0xFF));
                        bbb.Add(0xFF);
                    }
                }
                bbb.Add(0x00);
                bbb.Add(0x00);
            }
            bbb.RemoveRange(bbb.Count - 2, 2);
            bbb.Add(0x00);
            bbb.Add(0x01);
            int BmpSize = 54 + bbb.Count;

            bmp.Write(Bi(BmpSize)); //entire file size
            bmp.Write(Bi(0)); //unused
            bmp.Write(Bi(54)); //offset where bmp data is
            bmp.Write(Bi(40)); //size of DIB header
            bmp.Write(Bi(ResX));
            bmp.Write(Bi(ResY));
            bmp.Write(Bi(524289)); //plane count and bits per color
            bmp.Write(Bi(1)); //rle encoding used
            bmp.Write(Bi(bbb.Count)); //size of bmp data
            bmp.Write(Bi(2835)); //Some printer info idk
            bmp.Write(Bi(2835)); //Some printer info idk
            bmp.Write(Bi(256)); //color stuff
            bmp.Write(Bi(256)); //color stuff
            bmp.Write(bbb.ToArray());
            bmp.Flush();
        }

        private static byte[] Bi(int z)
        {
            return BitConverter.GetBytes(z);
        }
    }
}