/// <summary>
///
/// </summary>
/// <param name="r"></param>
/// <param name="heightMap"></param>
/// <param name="stepSize"></param>
/// <param name="scale"></param>
/// <param name="mapWidth"></param>
/// <param name="mapHeight"></param>
/// <returns></returns>
public static CyclicArray <int> Generate(Random r, CyclicArray <int> heightMap, int stepSize, double scale, int mapWidth, int mapHeight)
{
int halfStep = stepSize / 2;
int maxXTile = mapWidth;
int maxYTile = mapHeight;
for (int x = halfStep; x < (maxXTile + halfStep); x += stepSize)
{
for (int y = halfStep; y < (maxYTile + halfStep); y += stepSize)
{
int square = AverageSquare(heightMap, x, y, stepSize);
square += Convert.ToInt32(r.Next(0, 2) * scale);
heightMap[x, y] = square;
}
}
for (int x = 0; x < maxXTile; x += stepSize)
{
for (int y = 0; y < maxYTile; y += stepSize)
{
int diamondOne = AverageDiamond(heightMap, x + halfStep, y, stepSize);
diamondOne += Convert.ToInt32(r.Next(0, 2) * scale);
heightMap[x + halfStep, y] = diamondOne;
int diamondTwo = AverageDiamond(heightMap, x, y + halfStep, stepSize);
diamondTwo += Convert.ToInt32(r.Next(0, 2) * scale);
heightMap[x, y + halfStep] = diamondTwo;
}
}
return(heightMap);
}
/// <summary>
/// Calculate value of square centroid formed by `x`, `y` and `stepSize`.
/// </summary>
/// <param name="x">Left-edge position on x-axis.</param>
/// <param name="y">Top-edge position on y-axis.</param>
/// <param name="stepSize">Step size (Tiles).</param>
/// <returns></returns>
private static int AverageSquare(CyclicArray <int> heightMap, int x, int y, int stepSize)
{
int halfStep = stepSize / 2;
int NW = heightMap[x - halfStep, y - halfStep];
int SE = heightMap[x + halfStep, y + halfStep];
int SW = heightMap[x - halfStep, y + halfStep];
int NE = heightMap[x + halfStep, y - halfStep];
int average = (NE + SE + SW + NW) / 4;
return(average);
}
/// <summary>
/// Calculate value of diamond centroid formed by `x`, `y` and
/// `stepSize`.
/// </summary>
/// <param name="heightMap">Height map to work upon.</param>
/// <param name="x"></param>
/// <param name="y"></param>
/// <param name="stepSize"></param>
/// <returns></returns>
private static int AverageDiamond(CyclicArray <int> heightMap, int x, int y, int stepSize)
{
int halfStep = stepSize / 2;
int N = heightMap[x, y - halfStep];
int E = heightMap[x + halfStep, y];
int S = heightMap[x, y + halfStep];
int W = heightMap[x - halfStep, y];
int average = (N + E + S + W) / 4;
return(average);
}
/// <summary>
/// Constructor.
/// </summary>
/// <param name="r">Seeded random generator.</param>
/// <param name="g">Graphics context to draw to.</param>
/// <param name="width">Viewport width (pixels).</param>
/// <param name="height">Viewport height (pixels).</param>
public GameManager(Random r, Graphics g)
{
canvas = g;
random = r;
// Fetch next procedural map:
CyclicArray <int> mapCells = MapGenerator.NextMap(r, Conf.MapSize);
// Instantiate map:
terrainMap = new Map(canvas, mapCells, Conf.MapSize);
}
/// <summary>
///
/// </summary>
/// <param name="r"></param>
/// <param name="mapWidth"></param>
/// <param name="mapHeight"></param>
/// <returns></returns>
public static CyclicArray <int> NextMap(Random r, int mapSize)
{
int mapWidth = mapSize;
int mapHeight = mapSize;
//int[,] heightMap = new int[mapHeight, mapWidth];
CyclicArray <int> heightMap = new CyclicArray <int>();
CyclicArray <int> map = new CyclicArray <int>();
for (int row = 0; row < mapHeight; row++)
{
for (int column = 0; column < mapWidth; column++)
{
heightMap[row, column]
= r.Next(Conf.AltitudeMin, Conf.AltitudeMax + 1);
}
}
// Must be a power of 2:
int stepSize = Conf.StepSize;
// Noise-coefficient:
double scale = 1.777;
while (stepSize > 1)
{
DiamondSquare.Generate(r, heightMap, stepSize, scale, mapWidth, mapHeight);
stepSize /= 2;
scale /= 4.0;
}
DiamondSquare.Generate(r, heightMap, 1, scale, mapWidth, mapHeight);
// Min/max:
double min = Conf.AltitudeMin;
double max = Conf.AltitudeMax;
for (int row = 0; row < mapHeight; row++)
{
for (int column = 0; column < mapWidth; column++)
{
int tileAltitude = heightMap[row, column];
if (tileAltitude > max)
{
max = tileAltitude;
}
if (tileAltitude < min)
{
min = tileAltitude;
}
}
}
// Fill Map:
for (int row = 0; row < mapHeight; row++)
{
for (int column = 0; column < mapWidth; column++)
{
int tileAltitude = heightMap[row, column];
double altNormal = (tileAltitude - min) / (max - min);
altNormal *= Conf.AltitudeMax;
map[row, column] = tileAltitude;
}
}
return(map);
}
