private HexWalker GetNextExteriorSpot(HexWalker h)
{
Hex currentSpot = h.currentSpot;
Hex currentBoard = h.currentBoard;
List <Hex> neighbors = currentSpot.Neighbors();
// First, push forward the current board piece.
bool adjustBoardTile = true;
while (adjustBoardTile)
{
int direction = h.clockwise ? 1 : -1;
Hex nplus1 = neighbors[Mod((neighbors.IndexOf(currentBoard) + (1 * direction)), 6)];
Hex nplus2 = neighbors[Mod((neighbors.IndexOf(currentBoard) + (2 * direction)), 6)];
if (!pieces.ContainsKey(nplus1) && !pieces.ContainsKey(nplus2))
{
// Path is clear - dont adjust the board tile
adjustBoardTile = false;
currentSpot = nplus1;
}
else
{
// This is too tight an area!
currentBoard = pieces.ContainsKey(nplus2) ? nplus2 : nplus1;
}
}
return(new HexWalker(currentSpot, currentBoard, h.clockwise));
}
private void ShowStepSpots(int steps, Tile selectedTile)
{
Hex currentSpot = selectedTile.Hex;
Hex firstSpot = currentSpot;
List <Hex> allNeighborSpots = currentSpot.Neighbors();
bool[] boardNeighbors = { false, false, false, false, false, false };
for (int i = 0; i < 6; i++)
{
boardNeighbors[i] = pieces.ContainsKey(allNeighborSpots[i]);
if (boardNeighbors[i] && !boardNeighbors[Mod((i - 1), 6)])
{
if (i == 5 && boardNeighbors[0])
{
return; // Then we have a loop
}
// Found a spot to start highlighting from
Debug.Log("i:" + i + " o:" + firstSpot + " b:" + allNeighborSpots[i]);
HexWalker rwalker = new HexWalker(firstSpot, allNeighborSpots[i], true);
HexWalker lwalker = new HexWalker(firstSpot, allNeighborSpots[i], false);
for (int j = 0; j < steps; j++)
{
// Debug.Log(currentSpot);
rwalker = GetNextExteriorSpot(rwalker);
lwalker = GetNextExteriorSpot(lwalker);
}
ShowSpot(rwalker.currentSpot);
ShowSpot(lwalker.currentSpot);
}
}
}
public void CalculateDistancesBetweenTiles()
{
StringInputReader reader = new StringInputReader();
HexWalker walker = new HexWalker(reader);
Assert.Equal(3, walker.ShortestDistanceFromStart("ne,ne,ne"));
Assert.Equal(0, walker.ShortestDistanceFromStart("ne,ne,sw,sw"));
Assert.Equal(2, walker.ShortestDistanceFromStart("ne,ne,s,s"));
Assert.Equal(3, walker.ShortestDistanceFromStart("se,sw,se,sw,sw"));
}
private void ShowExteriorSpots(Tile selectedTile)
{
// Get the first on the outside path.
Hex mostRemoteHex = Hex.LongestHex(BoardHexes());
List <Hex> outerRing = Ring(mostRemoteHex.Length() + 1);
List <Hex> neighbors = mostRemoteHex.Neighbors();
Hex firstSpot = outerRing.Intersect(neighbors).First();
HexWalker walker = new HexWalker(firstSpot, mostRemoteHex, true);
do
{
// Debug.Log(currentSpot);
ShowSpot(walker.currentSpot);
walker = GetNextExteriorSpot(walker);
} while (!walker.currentSpot.Equals(firstSpot));
}
static void Main(string[] args)
{
/**
* I used the following extremely well-written guide by Amit Patel (Red Blob Games)
* to understand how a hexogonal grid can be represented and how one traverses it:
*
* https://www.redblobgames.com/grids/hexagons
*
* It's one of the most nicely-presented resources on game development that I've
* ever seen!
*/
FileInputReader reader = new FileInputReader();
HexWalker walker = new HexWalker(reader);
// Part one
Console.WriteLine(walker.ShortestDistanceFromStart("Inputs/day-11.txt"));
// Part two
Console.WriteLine(walker.FarthestDistanceFromStart("Inputs/day-11.txt"));
}
