/// <summary>
/// Generates the noise map.
/// From https://stackoverflow.com/questions/8659351/2d-perlin-noise
/// </summary>
/// <param name="width">The width.</param>
/// <param name="height">The height.</param>
/// <param name="result">The result.</param>
/// <param name="octaves">The octaves.</param>
public static void GenerateNoiseMap(int width, int height, int octaves, out DoubleOrSingle[] result)
{
var data = new DoubleOrSingle[width * height];
// track min and max noise value. Used to normalize the result to the 0 to 1.0 range.
var min = DoubleOrSingle.MaxValue;
var max = DoubleOrSingle.MinValue;
// rebuild the permutation table to get a different noise pattern.
// Leave this out if you want to play with changing the number of octaves while
// maintaining the same overall pattern.
Noise2d.Reseed();
var frequency = 0.5f;
var amplitude = 1f;
//var persistence = 0.25f;
for (var octave = 0; octave < octaves; octave++)
{
// parallel loop - easy and fast.
Parallel.For(0
, width * height
, (offset) =>
{
var i = offset % width;
var j = offset / width;
var noise = Noise2d.Noise(i * frequency * 1f / width, j * frequency * 1f / height);
noise = data[j * width + i] += noise * amplitude;
min = Math.Min(min, noise);
max = Math.Max(max, noise);
}
);
frequency *= 2;
amplitude /= 2;
}
//Normalize
for (int i = 0; i < data.Length; ++i)
{
data[i] = (data[i] - min) / (max - min);
}
result = data;
}
public void AddObstacles()
{
int width = MapConstants.mapWidth - 2;
int height = MapConstants.mapHeight - 2;
var data = new float[width * height];
var min = float.MaxValue;
var max = float.MinValue;
Noise2d.Reseed();
var frequency = 0.1f;
var amplitude = 1f;
for (int i = 0; i < data.Length; i++)
{
var x = i % width;
var y = i / width;
var noise = Noise2d.Noise(x * frequency * 1f / width, y * frequency * 1f / height);
noise = data[y * width + x] += noise * amplitude;
min = Math.Min(min, noise);
max = Math.Max(max, noise);
}
for (int i = 1; i < MapConstants.mapHeight - 1; i++)
{
for (int j = 1; j < MapConstants.mapWidth - 1; j++)
{
var normalizedNoise = (data[(i - 1) * (j - 1)] - min) / (max - min);
var obstacle = GetObstacleByNoise(normalizedNoise);
if (obstacle != null)
{
map[i, j] = obstacle;
}
}
}
}
