/// <summary>
/// Finds the shortest surface distance in the case of the points being on opposing faces.
/// This method is separate from CalculateShortestSurfaceDistance only for readability purposes.
/// </summary>
private static int OpposingFaceDistance(GridPoint start, GridPoint end)
{
List <int> distances = new List <int>();
GridZone gz = start.DetermineGridZone();
ExtendedGrid[] grids;
switch (gz)
{
case GridZone.TopLeft:
grids = new[]
{
ExtendedGrid.TopMiddle, ExtendedGrid.TopRight,
ExtendedGrid.RightMiddle,
ExtendedGrid.BotMiddle,
ExtendedGrid.LeftBot, ExtendedGrid.LeftMiddle
};
distances.AddRange(grids.Select(grid => CalculateDistanceOnExtendedGrid(grid, start, end)));
break;
case GridZone.TopMiddle:
grids = new[]
{
ExtendedGrid.TopLeft, ExtendedGrid.TopMiddle, ExtendedGrid.TopRight,
ExtendedGrid.RightMiddle, ExtendedGrid.RightBot,
ExtendedGrid.BotMiddle,
ExtendedGrid.LeftBot, ExtendedGrid.LeftMiddle
};
distances.AddRange(grids.Select(grid => CalculateDistanceOnExtendedGrid(grid, start, end)));
break;
case GridZone.TopRight:
grids = new[]
{
ExtendedGrid.TopLeft, ExtendedGrid.TopMiddle,
ExtendedGrid.RightMiddle, ExtendedGrid.RightBot,
ExtendedGrid.BotMiddle,
ExtendedGrid.LeftMiddle
};
distances.AddRange(grids.Select(grid => CalculateDistanceOnExtendedGrid(grid, start, end)));
break;
case GridZone.BottomLeft:
grids = new[]
{
ExtendedGrid.TopMiddle,
ExtendedGrid.RightMiddle,
ExtendedGrid.BotRight, ExtendedGrid.BotMiddle,
ExtendedGrid.LeftMiddle, ExtendedGrid.LeftTop
};
distances.AddRange(grids.Select(grid => CalculateDistanceOnExtendedGrid(grid, start, end)));
break;
case GridZone.BottomMiddle:
grids = new[]
{
ExtendedGrid.TopMiddle,
ExtendedGrid.RightTop, ExtendedGrid.RightMiddle,
ExtendedGrid.BotRight, ExtendedGrid.BotMiddle, ExtendedGrid.BotLeft,
ExtendedGrid.LeftMiddle, ExtendedGrid.LeftTop
};
distances.AddRange(grids.Select(grid => CalculateDistanceOnExtendedGrid(grid, start, end)));
break;
case GridZone.BottomRight:
grids = new[]
{
ExtendedGrid.TopMiddle,
ExtendedGrid.RightTop, ExtendedGrid.RightMiddle,
ExtendedGrid.BotMiddle, ExtendedGrid.BotLeft,
ExtendedGrid.LeftMiddle
};
distances.AddRange(grids.Select(grid => CalculateDistanceOnExtendedGrid(grid, start, end)));
break;
case GridZone.LeftMiddle:
grids = new[]
{
ExtendedGrid.TopMiddle, ExtendedGrid.TopRight,
ExtendedGrid.RightMiddle,
ExtendedGrid.BotRight, ExtendedGrid.BotMiddle,
ExtendedGrid.LeftBot, ExtendedGrid.LeftMiddle, ExtendedGrid.LeftTop
};
distances.AddRange(grids.Select(grid => CalculateDistanceOnExtendedGrid(grid, start, end)));
break;
case GridZone.RightMiddle:
grids = new[]
{
ExtendedGrid.TopLeft, ExtendedGrid.TopMiddle,
ExtendedGrid.RightTop, ExtendedGrid.RightMiddle, ExtendedGrid.RightBot,
ExtendedGrid.BotMiddle, ExtendedGrid.BotLeft,
ExtendedGrid.LeftMiddle
};
distances.AddRange(grids.Select(grid => CalculateDistanceOnExtendedGrid(grid, start, end)));
break;
default:
throw new Exception("uh oh...");
}
return(distances.Min());
}