Example - Cells further away in FOV are dimmer

Program.cs

public class Program
{
  private static double DistanceBetween( int x1, int y1, int x2, int y2 )
  {
     return Math.Sqrt( Math.Pow( x2 - x1, 2 ) + Math.Pow( y2 - y1, 2 ) );
  }

  private static int WalkingDistanceBetween( int x1, int y1, int x2, int y2 )
  {
     return Math.Abs( x2 - x1 ) + Math.Abs( y2 - y1 );
  }

  private static void OnRootConsoleRender( object sender, UpdateEventArgs e )
  {
     _map.ComputeFov( _partyX, _partyY, 50, true );

     foreach ( var cell in _map.GetAllCells() )
     {
        if ( cell.IsInFov )
        {
           int distance = WalkingDistanceBetween( _partyX, _partyY, cell.X, cell.Y );
           int blendValue = 256 - distance * 20;
           byte blendAmount = blendValue > 20 ? (byte) blendValue : (byte) 20;
           RLColor color = new RLColor( blendAmount, blendAmount, blendAmount );
           _map.SetCellProperties( cell.X, cell.Y, cell.IsTransparent, cell.IsWalkable, true );
           if ( cell.IsWalkable )
           {
              _mapConsole.Set( cell.X, cell.Y, color, null, 16 * 8 );
           }
           else
           {
              if ( cell.Y + 1 < _mapHeight && !_map.GetCell( cell.X, cell.Y + 1 ).IsWalkable )
              {
                 _mapConsole.Set( cell.X, cell.Y, color, null, 16 * 11 + 257 );
              }
              else
              {
                 _mapConsole.Set( cell.X, cell.Y, color, null, '#' + 256 );
              }
           }
        }
        else if ( cell.IsExplored )
        {
           if ( cell.IsWalkable )
           {
              _mapConsole.Set( cell.X, cell.Y, new RLColor( 30, 30, 30 ), null, '.' );
           }
           else
           {
              if ( cell.Y + 1 < _mapHeight && !_map.GetCell( cell.X, cell.Y + 1 ).IsWalkable )
              {
                 _mapConsole.Set( cell.X, cell.Y, RLColor.Gray, null, 16 * 11 + 257 );
              }
              else
              {
                 _mapConsole.Set( cell.X, cell.Y, RLColor.Gray, null, '#' + 256 );
              }
           }
        }
     }

     RLConsole.Blit( _mapConsole, 0, 0, _mapWidth, _mapHeight, _rootConsole, 1, 1 );

     _rootConsole.Draw();
  }
}

https://www.screencast.com/t/IThIy3QVZ