private void GenerateNoiseMap(int octaves, float persistence)
{
float z = Rand.Range(0.0f, 1.0f, Rand.RandSync.Server);
Noise = new float[generationParams.NoiseResolution, generationParams.NoiseResolution];
float min = float.MaxValue, max = 0.0f;
for (int x = 0; x < generationParams.NoiseResolution; x++)
{
for (int y = 0; y < generationParams.NoiseResolution; y++)
{
Noise[x, y] = (float)PerlinNoise.OctavePerlin(
(double)x / generationParams.NoiseResolution,
(double)y / generationParams.NoiseResolution,
z, generationParams.NoiseFrequency, octaves, persistence);
min = Math.Min(Noise[x, y], min);
max = Math.Max(Noise[x, y], max);
}
}
float radius = generationParams.NoiseResolution / 2;
Vector2 center = Vector2.One * radius;
float range = max - min;
float centerDarkenRadius = radius * generationParams.CenterDarkenRadius;
float edgeDarkenRadius = radius * generationParams.EdgeDarkenRadius;
for (int x = 0; x < generationParams.NoiseResolution; x++)
{
for (int y = 0; y < generationParams.NoiseResolution; y++)
{
//normalize the noise to 0-1 range
Noise[x, y] = (Noise[x, y] - min) / range;
float dist = Vector2.Distance(center, new Vector2(x, y));
if (dist < centerDarkenRadius)
{
float angle = (float)Math.Atan2(y - center.Y, x - center.X);
float phase = angle * generationParams.CenterDarkenWaveFrequency + Noise[x, y] * generationParams.CenterDarkenWavePhaseNoise;
float currDarkenRadius = centerDarkenRadius * (0.6f + (float)Math.Sin(phase) * 0.4f);
if (dist < currDarkenRadius)
{
float darkenAmount = 1.0f - (dist / currDarkenRadius);
Noise[x, y] = MathHelper.Lerp(Noise[x, y], Noise[x, y] * (1.0f - generationParams.CenterDarkenStrength), darkenAmount);
}
}
if (dist > edgeDarkenRadius)
{
float darkenAmount = Math.Min((dist - edgeDarkenRadius) / (radius - edgeDarkenRadius), 1.0f);
Noise[x, y] = MathHelper.Lerp(Noise[x, y], 1.0f - generationParams.EdgeDarkenStrength, darkenAmount);
}
}
}
}
