/// <summary>
/// Constructs a fractal with options for wrapping
/// </summary>
/// <param name="n">The largest fractal distance, must be a factor of 2. Good size is 128 or 256</param>
/// <param name="h">The number of vertical factals. Total height of the fractal is h*n</param>
/// <param name="w">The number of horizontal factals. Total height of the fractal is w*n</param>
/// <param name="options">Options for the lenth scale of the fractal</param>
/// <param name="wrapMode">Options for fractal wraping</param>
/// <returns></returns>
public static float[,] fractal(int n, int h, int w, FractalOptions options, FractalWrapMode wrapMode, uint seed = 0)
{
if (initSeed != 0)
{
random = new CoordRandom(initSeed);
}
else if (seed != 0)
{
random = new CoordRandom(seed);
}
else
{
random = new CoordRandom();
}
float[,] output = new float[n * w + 1, n *h + 1];
for (var i = 0; i < n * w + 1; i++)
{
for (var j = 0; j < n * h + 1; j++)
{
output[i, j] = Single.NaN;
}
}
int width = n * w;
if (wrapMode == FractalWrapMode.NoWrap)
{
width = n * w + 1;
}
int height = n * h + 1;
if (wrapMode == FractalWrapMode.Doughnut)
{
height = n * h;
}
random.SetWrapLimit(width, height);
for (int i = 0; i < w; i++)
{
for (int j = 0; j < h; j++)
{
fractal(w, h, n, i, j, options, ref output);
}
}
return(output);
}
private static void fractal(int w, int h, int n, int i, int j, FractalOptions options, ref float[,] map)
{
int length = n >> 1;
float scale = options.getScale(length);
//System.UnityEngine.Random UnityEngine.RandomNumber = new System.UnityEngine.Random();
int x0 = i * n;
int y0 = j * n;
int width = (i + 1) * n;
int height = (j + 1) * n;
map[i * n, j *n] = scale * (randomFloat(i * n, j * n) - 0.5f);
map[i * n, (j + 1) * n] = scale * (randomFloat(i * n, (j + 1) * n) - 0.5f);
map[(i + 1) * n, j *n] = scale * (randomFloat((i + 1) * n, j * n) - 0.5f);
map[(i + 1) * n, (j + 1) * n] = scale * (randomFloat((i + 1) * n, (j + 1) * n) - 0.5f);
while (length > 0)
{
//Debug.Log(length);
//diamond phase
//float lengthScale = length;//length*Terrain.activeTerrain.terrainData.heightmapScale.x;
scale = options.getScale(length);
int x = x0 + length;
while (x < width)
{
int y = y0 + length;
while (y < height)
{
if (Single.IsNaN(map[x, y]))
{
map[x, y] = (map[x - length, y - length] +
map[x + length, y - length] +
map[x + length, y + length] +
map[x - length, y + length]) / 4f +
scale * (randomFloat(x, y) - 0.5f);
}
y += 2 * length;
}
x += 2 * length;
}
//h =getScaleFactor(generation+0.5f);
//square phase
x = x0;
while (x <= width)
{
int y = y0;
while (y <= height)
{
if (Single.IsNaN(map[x, y]))
{
if (y == 0)
{
map[x, y] = (map[x, y + length] +
map[x + length, y] +
map[x - length, y]) / 3f +
scale * (randomFloat(x, y) - 0.5f);
}
else if (y == height)
{
map[x, y] = (map[x, y - length] +
map[x + length, y] +
map[x - length, y]) / 3f +
scale * (randomFloat(x, y) - 0.5f);
}
else if (x == 0)
{
map[x, y] = (map[x, y - length] +
map[x, y + length] +
map[x + length, y]) / 3f +
scale * (randomFloat(x, y) - 0.5f);
}
else if (x == width)
{
map[x, y] = (map[x, y - length] +
map[x, y + length] +
map[x - length, y]) / 3f +
scale * (randomFloat(x, y) - 0.5f);
}
else
{
/*if(Single.IsNaN(map[x][ y - length])){
* trace(x+", "+(y - length)+" has not been assigned");
* }
* if(Math.isNaN(map[x][ y + length])){
* trace(x+", "+(y + length)+" has not been assigned");
* }
* if(Math.isNaN(map[x + length][ y])){
* trace("a");
* }
* if(Math.isNaN(map[x - length][ y])){
* trace("b");
* }*/
map[x, y] = (map[x, y - length] +
map[x, y + length] +
map[x + length, y] +
map[x - length, y]) / 4f +
scale * (randomFloat(x, y) - 0.5f);
}
}
y += length;
}
x += length;
}
length = length >> 1;
}
}
